Patrick Dubroy
1441 lines
52 KiB
Java
1441 lines
52 KiB
Java
/*
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* Copyright (C) 2010 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package com.android.launcher2;
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import java.util.ArrayList;
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import android.content.Context;
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import android.content.res.TypedArray;
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import android.graphics.Canvas;
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import android.graphics.Rect;
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import android.os.Parcel;
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import android.os.Parcelable;
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import android.util.AttributeSet;
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import android.view.ActionMode;
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import android.view.MotionEvent;
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import android.view.VelocityTracker;
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import android.view.View;
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import android.view.ViewConfiguration;
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import android.view.ViewGroup;
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import android.view.ViewParent;
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import android.view.animation.Animation;
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import android.view.animation.Animation.AnimationListener;
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import android.view.animation.AnimationUtils;
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import android.view.animation.Interpolator;
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import android.widget.Checkable;
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import android.widget.Scroller;
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import com.android.launcher.R;
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/**
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* An abstraction of the original Workspace which supports browsing through a
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* sequential list of "pages"
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*/
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public abstract class PagedView extends ViewGroup {
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private static final String TAG = "PagedView";
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protected static final int INVALID_PAGE = -1;
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// the min drag distance for a fling to register, to prevent random page shifts
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private static final int MIN_LENGTH_FOR_FLING = 25;
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// The min drag distance to trigger a page shift (regardless of velocity)
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private static final int MIN_LENGTH_FOR_MOVE = 200;
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private static final int PAGE_SNAP_ANIMATION_DURATION = 550;
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protected static final float NANOTIME_DIV = 1000000000.0f;
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private static final float OVERSCROLL_DAMP_FACTOR = 0.08f;
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private static final int MINIMUM_SNAP_VELOCITY = 2200;
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private static final int MIN_FLING_VELOCITY = 250;
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// the velocity at which a fling gesture will cause us to snap to the next page
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protected int mSnapVelocity = 500;
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protected float mSmoothingTime;
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protected float mTouchX;
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protected boolean mFirstLayout = true;
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protected int mCurrentPage;
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protected int mNextPage = INVALID_PAGE;
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protected int mRestorePage = -1;
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protected int mMaxScrollX;
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protected Scroller mScroller;
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private VelocityTracker mVelocityTracker;
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private float mDownMotionX;
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protected float mLastMotionX;
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protected float mLastMotionY;
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private int mLastScreenCenter = -1;
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protected final static int TOUCH_STATE_REST = 0;
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protected final static int TOUCH_STATE_SCROLLING = 1;
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protected final static int TOUCH_STATE_PREV_PAGE = 2;
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protected final static int TOUCH_STATE_NEXT_PAGE = 3;
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protected final static float ALPHA_QUANTIZE_LEVEL = 0.0001f;
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protected int mTouchState = TOUCH_STATE_REST;
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protected OnLongClickListener mLongClickListener;
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protected boolean mAllowLongPress = true;
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protected int mTouchSlop;
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private int mPagingTouchSlop;
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private int mMaximumVelocity;
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protected int mPageSpacing;
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protected int mPageLayoutPaddingTop;
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protected int mPageLayoutPaddingBottom;
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protected int mPageLayoutPaddingLeft;
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protected int mPageLayoutPaddingRight;
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protected int mPageLayoutWidthGap;
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protected int mPageLayoutHeightGap;
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protected int mCellCountX;
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protected int mCellCountY;
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protected boolean mCenterPagesVertically;
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protected boolean mAllowOverScroll = true;
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protected int mUnboundedScrollX;
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// parameter that adjusts the layout to be optimized for CellLayouts with that scale factor
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protected float mLayoutScale = 1.0f;
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protected static final int INVALID_POINTER = -1;
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protected int mActivePointerId = INVALID_POINTER;
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private PageSwitchListener mPageSwitchListener;
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private ArrayList<Boolean> mDirtyPageContent;
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private boolean mDirtyPageAlpha;
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// choice modes
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protected static final int CHOICE_MODE_NONE = 0;
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protected static final int CHOICE_MODE_SINGLE = 1;
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// Multiple selection mode is not supported by all Launcher actions atm
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protected static final int CHOICE_MODE_MULTIPLE = 2;
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protected int mChoiceMode;
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private ActionMode mActionMode;
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// NOTE: This is a shared icon cache across all the PagedViews. Currently it is only used in
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// AllApps and Customize, and allows them to share holographic icons for the application view
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// (which is in both).
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protected static PagedViewIconCache mPageViewIconCache = new PagedViewIconCache();
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// If true, syncPages and syncPageItems will be called to refresh pages
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protected boolean mContentIsRefreshable = true;
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// If true, modify alpha of neighboring pages as user scrolls left/right
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protected boolean mFadeInAdjacentScreens = true;
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// It true, use a different slop parameter (pagingTouchSlop = 2 * touchSlop) for deciding
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// to switch to a new page
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protected boolean mUsePagingTouchSlop = true;
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// If true, the subclass should directly update mScrollX itself in its computeScroll method
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// (SmoothPagedView does this)
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protected boolean mDeferScrollUpdate = false;
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protected boolean mIsPageMoving = false;
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public interface PageSwitchListener {
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void onPageSwitch(View newPage, int newPageIndex);
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}
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public PagedView(Context context) {
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this(context, null);
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}
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public PagedView(Context context, AttributeSet attrs) {
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this(context, attrs, 0);
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}
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public PagedView(Context context, AttributeSet attrs, int defStyle) {
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super(context, attrs, defStyle);
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mChoiceMode = CHOICE_MODE_NONE;
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TypedArray a = context.obtainStyledAttributes(attrs,
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R.styleable.PagedView, defStyle, 0);
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mPageSpacing = a.getDimensionPixelSize(R.styleable.PagedView_pageSpacing, 0);
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mPageLayoutPaddingTop = a.getDimensionPixelSize(
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R.styleable.PagedView_pageLayoutPaddingTop, 10);
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mPageLayoutPaddingBottom = a.getDimensionPixelSize(
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R.styleable.PagedView_pageLayoutPaddingBottom, 10);
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mPageLayoutPaddingLeft = a.getDimensionPixelSize(
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R.styleable.PagedView_pageLayoutPaddingLeft, 10);
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mPageLayoutPaddingRight = a.getDimensionPixelSize(
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R.styleable.PagedView_pageLayoutPaddingRight, 10);
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mPageLayoutWidthGap = a.getDimensionPixelSize(
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R.styleable.PagedView_pageLayoutWidthGap, -1);
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mPageLayoutHeightGap = a.getDimensionPixelSize(
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R.styleable.PagedView_pageLayoutHeightGap, -1);
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a.recycle();
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setHapticFeedbackEnabled(false);
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init();
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}
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/**
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* Initializes various states for this workspace.
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*/
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protected void init() {
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mDirtyPageContent = new ArrayList<Boolean>();
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mDirtyPageContent.ensureCapacity(32);
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mScroller = new Scroller(getContext(), new ScrollInterpolator());
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mCurrentPage = 0;
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mCenterPagesVertically = true;
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final ViewConfiguration configuration = ViewConfiguration.get(getContext());
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mTouchSlop = configuration.getScaledTouchSlop();
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mPagingTouchSlop = configuration.getScaledPagingTouchSlop();
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mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();
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}
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public void setPageSwitchListener(PageSwitchListener pageSwitchListener) {
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mPageSwitchListener = pageSwitchListener;
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if (mPageSwitchListener != null) {
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mPageSwitchListener.onPageSwitch(getPageAt(mCurrentPage), mCurrentPage);
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}
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}
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/**
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* Returns the index of the currently displayed page.
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*
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* @return The index of the currently displayed page.
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*/
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int getCurrentPage() {
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return mCurrentPage;
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}
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int getPageCount() {
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return getChildCount();
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}
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View getPageAt(int index) {
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return getChildAt(index);
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}
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int getScrollWidth() {
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return getWidth();
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}
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/**
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* Updates the scroll of the current page immediately to its final scroll position. We use this
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* in CustomizePagedView to allow tabs to share the same PagedView while resetting the scroll of
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* the previous tab page.
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*/
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protected void updateCurrentPageScroll() {
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int newX = getChildOffset(mCurrentPage) - getRelativeChildOffset(mCurrentPage);
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scrollTo(newX, 0);
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mScroller.setFinalX(newX);
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}
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/**
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* Sets the current page.
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*/
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void setCurrentPage(int currentPage) {
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if (!mScroller.isFinished()) {
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mScroller.abortAnimation();
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}
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// don't introduce any checks like mCurrentPage == currentPage here-- if we change the
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// the default
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if (getChildCount() == 0) {
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return;
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}
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mCurrentPage = Math.max(0, Math.min(currentPage, getPageCount() - 1));
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updateCurrentPageScroll();
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notifyPageSwitchListener();
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invalidate();
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}
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protected void notifyPageSwitchListener() {
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if (mPageSwitchListener != null) {
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mPageSwitchListener.onPageSwitch(getPageAt(mCurrentPage), mCurrentPage);
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}
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}
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private void pageBeginMoving() {
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mIsPageMoving = true;
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onPageBeginMoving();
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}
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private void pageEndMoving() {
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onPageEndMoving();
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mIsPageMoving = false;
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}
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// a method that subclasses can override to add behavior
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protected void onPageBeginMoving() {
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}
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// a method that subclasses can override to add behavior
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protected void onPageEndMoving() {
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}
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/**
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* Registers the specified listener on each page contained in this workspace.
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*
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* @param l The listener used to respond to long clicks.
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*/
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@Override
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public void setOnLongClickListener(OnLongClickListener l) {
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mLongClickListener = l;
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final int count = getPageCount();
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for (int i = 0; i < count; i++) {
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getPageAt(i).setOnLongClickListener(l);
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}
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}
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@Override
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public void scrollBy(int x, int y) {
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scrollTo(mUnboundedScrollX + x, mScrollY + y);
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}
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@Override
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public void scrollTo(int x, int y) {
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mUnboundedScrollX = x;
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if (x < 0) {
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super.scrollTo(0, y);
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if (mAllowOverScroll) {
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overScroll(x);
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}
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} else if (x > mMaxScrollX) {
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super.scrollTo(mMaxScrollX, y);
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if (mAllowOverScroll) {
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overScroll(x - mMaxScrollX);
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}
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} else {
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super.scrollTo(x, y);
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}
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mTouchX = x;
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mSmoothingTime = System.nanoTime() / NANOTIME_DIV;
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}
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// we moved this functionality to a helper function so SmoothPagedView can reuse it
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protected boolean computeScrollHelper() {
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if (mScroller.computeScrollOffset()) {
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mDirtyPageAlpha = true;
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scrollTo(mScroller.getCurrX(), mScroller.getCurrY());
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invalidate();
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return true;
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} else if (mNextPage != INVALID_PAGE) {
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mDirtyPageAlpha = true;
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mCurrentPage = Math.max(0, Math.min(mNextPage, getPageCount() - 1));
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mNextPage = INVALID_PAGE;
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notifyPageSwitchListener();
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// We don't want to trigger a page end moving unless the page has settled
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// and the user has stopped scrolling
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if (mTouchState == TOUCH_STATE_REST) {
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pageEndMoving();
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}
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return true;
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}
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return false;
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}
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@Override
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public void computeScroll() {
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computeScrollHelper();
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}
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@Override
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protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
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final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
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final int widthSize = MeasureSpec.getSize(widthMeasureSpec);
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if (widthMode != MeasureSpec.EXACTLY) {
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throw new IllegalStateException("Workspace can only be used in EXACTLY mode.");
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}
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/* Allow the height to be set as WRAP_CONTENT. This allows the particular case
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* of the All apps view on XLarge displays to not take up more space then it needs. Width
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* is still not allowed to be set as WRAP_CONTENT since many parts of the code expect
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* each page to have the same width.
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*/
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final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
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int heightSize = MeasureSpec.getSize(heightMeasureSpec);
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int maxChildHeight = 0;
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final int verticalPadding = mPaddingTop + mPaddingBottom;
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// The children are given the same width and height as the workspace
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// unless they were set to WRAP_CONTENT
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final int childCount = getChildCount();
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for (int i = 0; i < childCount; i++) {
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// disallowing padding in paged view (just pass 0)
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final View child = getChildAt(i);
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final LayoutParams lp = (LayoutParams) child.getLayoutParams();
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int childWidthMode;
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if (lp.width == LayoutParams.WRAP_CONTENT) {
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childWidthMode = MeasureSpec.AT_MOST;
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} else {
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childWidthMode = MeasureSpec.EXACTLY;
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}
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int childHeightMode;
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if (lp.height == LayoutParams.WRAP_CONTENT) {
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childHeightMode = MeasureSpec.AT_MOST;
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} else {
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childHeightMode = MeasureSpec.EXACTLY;
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}
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final int childWidthMeasureSpec =
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MeasureSpec.makeMeasureSpec(widthSize, childWidthMode);
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final int childHeightMeasureSpec =
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MeasureSpec.makeMeasureSpec(heightSize - verticalPadding, childHeightMode);
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child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
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maxChildHeight = Math.max(maxChildHeight, child.getMeasuredHeight());
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}
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if (heightMode == MeasureSpec.AT_MOST) {
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heightSize = maxChildHeight + verticalPadding;
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}
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if (childCount > 0) {
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mMaxScrollX = getChildOffset(childCount - 1) - getRelativeChildOffset(childCount - 1);
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} else {
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mMaxScrollX = 0;
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}
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setMeasuredDimension(widthSize, heightSize);
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}
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protected void moveToNewPageWithoutMovingCellLayouts(int newCurrentPage) {
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int newX = getChildOffset(newCurrentPage) - getRelativeChildOffset(newCurrentPage);
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int delta = newX - mScrollX;
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final int screenCount = getChildCount();
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for (int i = 0; i < screenCount; i++) {
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CellLayout cl = (CellLayout) getChildAt(i);
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cl.setX(cl.getX() + delta);
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}
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setCurrentPage(newCurrentPage);
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}
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// A layout scale of 1.0f assumes that the CellLayouts, in their unshrunken state, have a
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// scale of 1.0f. A layout scale of 0.8f assumes the CellLayouts have a scale of 0.8f, and
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// tightens the layout accordingly
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public void setLayoutScale(float childrenScale) {
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mLayoutScale = childrenScale;
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// Now we need to do a re-layout, but preserving absolute X and Y coordinates
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int childCount = getChildCount();
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float childrenX[] = new float[childCount];
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float childrenY[] = new float[childCount];
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for (int i = 0; i < childCount; i++) {
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final View child = getChildAt(i);
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childrenX[i] = child.getX();
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childrenY[i] = child.getY();
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}
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onLayout(false, mLeft, mTop, mRight, mBottom);
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for (int i = 0; i < childCount; i++) {
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final View child = getChildAt(i);
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child.setX(childrenX[i]);
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child.setY(childrenY[i]);
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}
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// Also, the page offset has changed (since the pages are now smaller);
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// update the page offset, but again preserving absolute X and Y coordinates
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moveToNewPageWithoutMovingCellLayouts(mCurrentPage);
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}
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@Override
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protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
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if (mFirstLayout && mCurrentPage >= 0 && mCurrentPage < getChildCount()) {
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setHorizontalScrollBarEnabled(false);
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int newX = getChildOffset(mCurrentPage) - getRelativeChildOffset(mCurrentPage);
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scrollTo(newX, 0);
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mScroller.setFinalX(newX);
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setHorizontalScrollBarEnabled(true);
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mFirstLayout = false;
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}
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final int verticalPadding = mPaddingTop + mPaddingBottom;
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final int childCount = getChildCount();
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int childLeft = 0;
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if (childCount > 0) {
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childLeft = getRelativeChildOffset(0);
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}
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for (int i = 0; i < childCount; i++) {
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final View child = getChildAt(i);
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if (child.getVisibility() != View.GONE) {
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final int childWidth = getScaledMeasuredWidth(child);
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final int childHeight = child.getMeasuredHeight();
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int childTop = mPaddingTop;
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if (mCenterPagesVertically) {
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childTop += ((getMeasuredHeight() - verticalPadding) - childHeight) / 2;
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}
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child.layout(childLeft, childTop,
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childLeft + child.getMeasuredWidth(), childTop + childHeight);
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childLeft += childWidth + mPageSpacing;
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}
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}
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if (mFirstLayout && mCurrentPage >= 0 && mCurrentPage < getChildCount()) {
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mFirstLayout = false;
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}
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}
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protected void updateAdjacentPagesAlpha() {
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if (mFadeInAdjacentScreens) {
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if (mDirtyPageAlpha || (mTouchState == TOUCH_STATE_SCROLLING) || !mScroller.isFinished()) {
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int halfScreenSize = getMeasuredWidth() / 2;
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int screenCenter = mScrollX + halfScreenSize;
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final int childCount = getChildCount();
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for (int i = 0; i < childCount; ++i) {
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View layout = (View) getChildAt(i);
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int childWidth = getScaledMeasuredWidth(layout);
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int halfChildWidth = (childWidth / 2);
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int childCenter = getChildOffset(i) + halfChildWidth;
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// On the first layout, we may not have a width nor a proper offset, so for now
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// we should just assume full page width (and calculate the offset according to
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// that).
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if (childWidth <= 0) {
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childWidth = getMeasuredWidth();
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childCenter = (i * childWidth) + (childWidth / 2);
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}
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int d = halfChildWidth;
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int distanceFromScreenCenter = childCenter - screenCenter;
|
|
if (distanceFromScreenCenter > 0) {
|
|
if (i > 0) {
|
|
d += getScaledMeasuredWidth(getChildAt(i - 1)) / 2;
|
|
}
|
|
} else {
|
|
if (i < childCount - 1) {
|
|
d += getScaledMeasuredWidth(getChildAt(i + 1)) / 2;
|
|
}
|
|
}
|
|
d += mPageSpacing;
|
|
|
|
// Preventing potential divide-by-zero
|
|
d = Math.max(1, d);
|
|
|
|
float dimAlpha = (float) (Math.abs(distanceFromScreenCenter)) / d;
|
|
dimAlpha = Math.max(0.0f, Math.min(1.0f, (dimAlpha * dimAlpha)));
|
|
float alpha = 1.0f - dimAlpha;
|
|
|
|
if (alpha < ALPHA_QUANTIZE_LEVEL) {
|
|
alpha = 0.0f;
|
|
} else if (alpha > 1.0f - ALPHA_QUANTIZE_LEVEL) {
|
|
alpha = 1.0f;
|
|
}
|
|
|
|
if (Float.compare(alpha, layout.getAlpha()) != 0) {
|
|
layout.setAlpha(alpha);
|
|
}
|
|
}
|
|
mDirtyPageAlpha = false;
|
|
}
|
|
}
|
|
}
|
|
|
|
protected void screenScrolled(int screenCenter) {
|
|
}
|
|
|
|
@Override
|
|
protected void dispatchDraw(Canvas canvas) {
|
|
int halfScreenSize = getMeasuredWidth() / 2;
|
|
int screenCenter = mScrollX + halfScreenSize;
|
|
|
|
if (screenCenter != mLastScreenCenter) {
|
|
screenScrolled(screenCenter);
|
|
updateAdjacentPagesAlpha();
|
|
mLastScreenCenter = screenCenter;
|
|
}
|
|
|
|
// Find out which screens are visible; as an optimization we only call draw on them
|
|
// As an optimization, this code assumes that all pages have the same width as the 0th
|
|
// page.
|
|
final int pageCount = getChildCount();
|
|
if (pageCount > 0) {
|
|
final int pageWidth = getScaledMeasuredWidth(getChildAt(0));
|
|
final int screenWidth = getMeasuredWidth();
|
|
int x = getRelativeChildOffset(0) + pageWidth;
|
|
int leftScreen = 0;
|
|
int rightScreen = 0;
|
|
while (x <= mScrollX) {
|
|
leftScreen++;
|
|
x += getScaledMeasuredWidth(getChildAt(leftScreen)) + mPageSpacing;
|
|
}
|
|
rightScreen = leftScreen;
|
|
while (x < mScrollX + screenWidth && rightScreen < pageCount) {
|
|
rightScreen++;
|
|
if (rightScreen < pageCount) {
|
|
x += getScaledMeasuredWidth(getChildAt(rightScreen)) + mPageSpacing;
|
|
}
|
|
}
|
|
rightScreen = Math.min(getChildCount() - 1, rightScreen);
|
|
|
|
final long drawingTime = getDrawingTime();
|
|
// Clip to the bounds
|
|
canvas.save();
|
|
canvas.clipRect(mScrollX, mScrollY, mScrollX + mRight - mLeft,
|
|
mScrollY + mBottom - mTop);
|
|
|
|
for (int i = leftScreen; i <= rightScreen; i++) {
|
|
drawChild(canvas, getChildAt(i), drawingTime);
|
|
}
|
|
canvas.restore();
|
|
}
|
|
}
|
|
|
|
@Override
|
|
public boolean requestChildRectangleOnScreen(View child, Rect rectangle, boolean immediate) {
|
|
int page = indexOfChild(child);
|
|
if (page != mCurrentPage || !mScroller.isFinished()) {
|
|
snapToPage(page);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
@Override
|
|
protected boolean onRequestFocusInDescendants(int direction, Rect previouslyFocusedRect) {
|
|
int focusablePage;
|
|
if (mNextPage != INVALID_PAGE) {
|
|
focusablePage = mNextPage;
|
|
} else {
|
|
focusablePage = mCurrentPage;
|
|
}
|
|
View v = getPageAt(focusablePage);
|
|
if (v != null) {
|
|
v.requestFocus(direction, previouslyFocusedRect);
|
|
}
|
|
return false;
|
|
}
|
|
|
|
@Override
|
|
public boolean dispatchUnhandledMove(View focused, int direction) {
|
|
if (direction == View.FOCUS_LEFT) {
|
|
if (getCurrentPage() > 0) {
|
|
snapToPage(getCurrentPage() - 1);
|
|
return true;
|
|
}
|
|
} else if (direction == View.FOCUS_RIGHT) {
|
|
if (getCurrentPage() < getPageCount() - 1) {
|
|
snapToPage(getCurrentPage() + 1);
|
|
return true;
|
|
}
|
|
}
|
|
return super.dispatchUnhandledMove(focused, direction);
|
|
}
|
|
|
|
@Override
|
|
public void addFocusables(ArrayList<View> views, int direction, int focusableMode) {
|
|
if (mCurrentPage >= 0 && mCurrentPage < getPageCount()) {
|
|
getPageAt(mCurrentPage).addFocusables(views, direction);
|
|
}
|
|
if (direction == View.FOCUS_LEFT) {
|
|
if (mCurrentPage > 0) {
|
|
getPageAt(mCurrentPage - 1).addFocusables(views, direction);
|
|
}
|
|
} else if (direction == View.FOCUS_RIGHT){
|
|
if (mCurrentPage < getPageCount() - 1) {
|
|
getPageAt(mCurrentPage + 1).addFocusables(views, direction);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* If one of our descendant views decides that it could be focused now, only
|
|
* pass that along if it's on the current page.
|
|
*
|
|
* This happens when live folders requery, and if they're off page, they
|
|
* end up calling requestFocus, which pulls it on page.
|
|
*/
|
|
@Override
|
|
public void focusableViewAvailable(View focused) {
|
|
View current = getPageAt(mCurrentPage);
|
|
View v = focused;
|
|
while (true) {
|
|
if (v == current) {
|
|
super.focusableViewAvailable(focused);
|
|
return;
|
|
}
|
|
if (v == this) {
|
|
return;
|
|
}
|
|
ViewParent parent = v.getParent();
|
|
if (parent instanceof View) {
|
|
v = (View)v.getParent();
|
|
} else {
|
|
return;
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* {@inheritDoc}
|
|
*/
|
|
@Override
|
|
public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) {
|
|
if (disallowIntercept) {
|
|
// We need to make sure to cancel our long press if
|
|
// a scrollable widget takes over touch events
|
|
final View currentPage = getChildAt(mCurrentPage);
|
|
currentPage.cancelLongPress();
|
|
}
|
|
super.requestDisallowInterceptTouchEvent(disallowIntercept);
|
|
}
|
|
|
|
/**
|
|
* Return true if a tap at (x, y) should trigger a flip to the previous page.
|
|
*/
|
|
protected boolean hitsPreviousPage(float x, float y) {
|
|
return (x < getRelativeChildOffset(mCurrentPage) - mPageSpacing);
|
|
}
|
|
|
|
/**
|
|
* Return true if a tap at (x, y) should trigger a flip to the next page.
|
|
*/
|
|
protected boolean hitsNextPage(float x, float y) {
|
|
return (x > (getMeasuredWidth() - getRelativeChildOffset(mCurrentPage) + mPageSpacing));
|
|
}
|
|
|
|
@Override
|
|
public boolean onInterceptTouchEvent(MotionEvent ev) {
|
|
/*
|
|
* This method JUST determines whether we want to intercept the motion.
|
|
* If we return true, onTouchEvent will be called and we do the actual
|
|
* scrolling there.
|
|
*/
|
|
|
|
// Skip touch handling if there are no pages to swipe
|
|
if (getChildCount() <= 0) return super.onInterceptTouchEvent(ev);
|
|
|
|
/*
|
|
* Shortcut the most recurring case: the user is in the dragging
|
|
* state and he is moving his finger. We want to intercept this
|
|
* motion.
|
|
*/
|
|
final int action = ev.getAction();
|
|
if ((action == MotionEvent.ACTION_MOVE) &&
|
|
(mTouchState == TOUCH_STATE_SCROLLING)) {
|
|
return true;
|
|
}
|
|
|
|
switch (action & MotionEvent.ACTION_MASK) {
|
|
case MotionEvent.ACTION_MOVE: {
|
|
/*
|
|
* mIsBeingDragged == false, otherwise the shortcut would have caught it. Check
|
|
* whether the user has moved far enough from his original down touch.
|
|
*/
|
|
if (mActivePointerId != INVALID_POINTER) {
|
|
determineScrollingStart(ev);
|
|
break;
|
|
}
|
|
// if mActivePointerId is INVALID_POINTER, then we must have missed an ACTION_DOWN
|
|
// event. in that case, treat the first occurence of a move event as a ACTION_DOWN
|
|
// i.e. fall through to the next case (don't break)
|
|
// (We sometimes miss ACTION_DOWN events in Workspace because it ignores all events
|
|
// while it's small- this was causing a crash before we checked for INVALID_POINTER)
|
|
}
|
|
|
|
case MotionEvent.ACTION_DOWN: {
|
|
final float x = ev.getX();
|
|
final float y = ev.getY();
|
|
// Remember location of down touch
|
|
mDownMotionX = x;
|
|
mLastMotionX = x;
|
|
mLastMotionY = y;
|
|
mActivePointerId = ev.getPointerId(0);
|
|
mAllowLongPress = true;
|
|
|
|
/*
|
|
* If being flinged and user touches the screen, initiate drag;
|
|
* otherwise don't. mScroller.isFinished should be false when
|
|
* being flinged.
|
|
*/
|
|
final int xDist = Math.abs(mScroller.getFinalX() - mScroller.getCurrX());
|
|
final boolean finishedScrolling = (mScroller.isFinished() || xDist < mTouchSlop);
|
|
if (finishedScrolling) {
|
|
mTouchState = TOUCH_STATE_REST;
|
|
mScroller.abortAnimation();
|
|
} else {
|
|
mTouchState = TOUCH_STATE_SCROLLING;
|
|
}
|
|
|
|
// check if this can be the beginning of a tap on the side of the pages
|
|
// to scroll the current page
|
|
if (mTouchState != TOUCH_STATE_PREV_PAGE && mTouchState != TOUCH_STATE_NEXT_PAGE) {
|
|
if (getChildCount() > 0) {
|
|
if (hitsPreviousPage(x, y)) {
|
|
mTouchState = TOUCH_STATE_PREV_PAGE;
|
|
} else if (hitsNextPage(x, y)) {
|
|
mTouchState = TOUCH_STATE_NEXT_PAGE;
|
|
}
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
case MotionEvent.ACTION_UP:
|
|
onWallpaperTap(ev);
|
|
case MotionEvent.ACTION_CANCEL:
|
|
mTouchState = TOUCH_STATE_REST;
|
|
mAllowLongPress = false;
|
|
mActivePointerId = INVALID_POINTER;
|
|
break;
|
|
|
|
case MotionEvent.ACTION_POINTER_UP:
|
|
onSecondaryPointerUp(ev);
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* The only time we want to intercept motion events is if we are in the
|
|
* drag mode.
|
|
*/
|
|
return mTouchState != TOUCH_STATE_REST;
|
|
}
|
|
|
|
protected void animateClickFeedback(View v, final Runnable r) {
|
|
// animate the view slightly to show click feedback running some logic after it is "pressed"
|
|
Animation anim = AnimationUtils.loadAnimation(getContext(),
|
|
R.anim.paged_view_click_feedback);
|
|
anim.setAnimationListener(new AnimationListener() {
|
|
@Override
|
|
public void onAnimationStart(Animation animation) {}
|
|
@Override
|
|
public void onAnimationRepeat(Animation animation) {
|
|
r.run();
|
|
}
|
|
@Override
|
|
public void onAnimationEnd(Animation animation) {}
|
|
});
|
|
v.startAnimation(anim);
|
|
}
|
|
|
|
/*
|
|
* Determines if we should change the touch state to start scrolling after the
|
|
* user moves their touch point too far.
|
|
*/
|
|
protected void determineScrollingStart(MotionEvent ev) {
|
|
/*
|
|
* Locally do absolute value. mLastMotionX is set to the y value
|
|
* of the down event.
|
|
*/
|
|
final int pointerIndex = ev.findPointerIndex(mActivePointerId);
|
|
final float x = ev.getX(pointerIndex);
|
|
final float y = ev.getY(pointerIndex);
|
|
final int xDiff = (int) Math.abs(x - mLastMotionX);
|
|
final int yDiff = (int) Math.abs(y - mLastMotionY);
|
|
|
|
final int touchSlop = mTouchSlop;
|
|
boolean xPaged = xDiff > mPagingTouchSlop;
|
|
boolean xMoved = xDiff > touchSlop;
|
|
boolean yMoved = yDiff > touchSlop;
|
|
|
|
if (xMoved || yMoved) {
|
|
if (mUsePagingTouchSlop ? xPaged : xMoved) {
|
|
// Scroll if the user moved far enough along the X axis
|
|
mTouchState = TOUCH_STATE_SCROLLING;
|
|
mLastMotionX = x;
|
|
mTouchX = mScrollX;
|
|
mSmoothingTime = System.nanoTime() / NANOTIME_DIV;
|
|
pageBeginMoving();
|
|
}
|
|
// Either way, cancel any pending longpress
|
|
if (mAllowLongPress) {
|
|
mAllowLongPress = false;
|
|
// Try canceling the long press. It could also have been scheduled
|
|
// by a distant descendant, so use the mAllowLongPress flag to block
|
|
// everything
|
|
final View currentPage = getPageAt(mCurrentPage);
|
|
if (currentPage != null) {
|
|
currentPage.cancelLongPress();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// This curve determines how the effect of scrolling over the limits of the page dimishes
|
|
// as the user pulls further and further from the bounds
|
|
private float overScrollInfluenceCurve(float f) {
|
|
f -= 1.0f;
|
|
return f * f * f + 1.0f;
|
|
}
|
|
|
|
protected void overScroll(float amount) {
|
|
int screenSize = getMeasuredWidth();
|
|
|
|
float f = (amount / screenSize);
|
|
|
|
if (f == 0) return;
|
|
f = f / (Math.abs(f)) * (overScrollInfluenceCurve(Math.abs(f)));
|
|
|
|
int overScrollAmount = (int) Math.round(OVERSCROLL_DAMP_FACTOR * f * screenSize);
|
|
if (amount < 0) {
|
|
mScrollX = overScrollAmount;
|
|
} else {
|
|
mScrollX = mMaxScrollX + overScrollAmount;
|
|
}
|
|
invalidate();
|
|
}
|
|
|
|
protected float maxOverScroll() {
|
|
// Using the formula in overScroll, assuming that f = 1.0 (which it should generally not
|
|
// exceed). Used to find out how much extra wallpaper we need for the overscroll effect
|
|
float f = 1.0f;
|
|
f = f / (Math.abs(f)) * (overScrollInfluenceCurve(Math.abs(f)));
|
|
return OVERSCROLL_DAMP_FACTOR * f;
|
|
}
|
|
|
|
@Override
|
|
public boolean onTouchEvent(MotionEvent ev) {
|
|
// Skip touch handling if there are no pages to swipe
|
|
if (getChildCount() <= 0) return super.onTouchEvent(ev);
|
|
|
|
acquireVelocityTrackerAndAddMovement(ev);
|
|
|
|
final int action = ev.getAction();
|
|
|
|
switch (action & MotionEvent.ACTION_MASK) {
|
|
case MotionEvent.ACTION_DOWN:
|
|
/*
|
|
* If being flinged and user touches, stop the fling. isFinished
|
|
* will be false if being flinged.
|
|
*/
|
|
if (!mScroller.isFinished()) {
|
|
mScroller.abortAnimation();
|
|
}
|
|
|
|
// Remember where the motion event started
|
|
mDownMotionX = mLastMotionX = ev.getX();
|
|
mActivePointerId = ev.getPointerId(0);
|
|
if (mTouchState == TOUCH_STATE_SCROLLING) {
|
|
pageBeginMoving();
|
|
}
|
|
break;
|
|
|
|
case MotionEvent.ACTION_MOVE:
|
|
if (mTouchState == TOUCH_STATE_SCROLLING) {
|
|
// Scroll to follow the motion event
|
|
final int pointerIndex = ev.findPointerIndex(mActivePointerId);
|
|
final float x = ev.getX(pointerIndex);
|
|
final int deltaX = (int) (mLastMotionX - x);
|
|
mLastMotionX = x;
|
|
|
|
if (deltaX != 0) {
|
|
mTouchX += deltaX;
|
|
mSmoothingTime = System.nanoTime() / NANOTIME_DIV;
|
|
if (!mDeferScrollUpdate) {
|
|
scrollBy(deltaX, 0);
|
|
} else {
|
|
invalidate();
|
|
}
|
|
} else {
|
|
awakenScrollBars();
|
|
}
|
|
} else {
|
|
determineScrollingStart(ev);
|
|
}
|
|
break;
|
|
|
|
case MotionEvent.ACTION_UP:
|
|
if (mTouchState == TOUCH_STATE_SCROLLING) {
|
|
final int activePointerId = mActivePointerId;
|
|
final int pointerIndex = ev.findPointerIndex(activePointerId);
|
|
final float x = ev.getX(pointerIndex);
|
|
final VelocityTracker velocityTracker = mVelocityTracker;
|
|
velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
|
|
int velocityX = (int) velocityTracker.getXVelocity(activePointerId);
|
|
final int deltaX = (int) (x - mDownMotionX);
|
|
boolean isfling = Math.abs(deltaX) > MIN_LENGTH_FOR_FLING;
|
|
boolean isSignificantMove = Math.abs(deltaX) > MIN_LENGTH_FOR_MOVE;
|
|
|
|
final int snapVelocity = mSnapVelocity;
|
|
if ((isSignificantMove && deltaX > 0 ||
|
|
(isfling && velocityX > snapVelocity)) && mCurrentPage > 0) {
|
|
snapToPageWithVelocity(mCurrentPage - 1, velocityX);
|
|
} else if ((isSignificantMove && deltaX < 0 ||
|
|
(isfling && velocityX < -snapVelocity)) &&
|
|
mCurrentPage < getChildCount() - 1) {
|
|
snapToPageWithVelocity(mCurrentPage + 1, velocityX);
|
|
} else {
|
|
snapToDestination();
|
|
}
|
|
} else if (mTouchState == TOUCH_STATE_PREV_PAGE) {
|
|
// at this point we have not moved beyond the touch slop
|
|
// (otherwise mTouchState would be TOUCH_STATE_SCROLLING), so
|
|
// we can just page
|
|
int nextPage = Math.max(0, mCurrentPage - 1);
|
|
if (nextPage != mCurrentPage) {
|
|
snapToPage(nextPage);
|
|
} else {
|
|
snapToDestination();
|
|
}
|
|
} else if (mTouchState == TOUCH_STATE_NEXT_PAGE) {
|
|
// at this point we have not moved beyond the touch slop
|
|
// (otherwise mTouchState would be TOUCH_STATE_SCROLLING), so
|
|
// we can just page
|
|
int nextPage = Math.min(getChildCount() - 1, mCurrentPage + 1);
|
|
if (nextPage != mCurrentPage) {
|
|
snapToPage(nextPage);
|
|
} else {
|
|
snapToDestination();
|
|
}
|
|
} else {
|
|
onWallpaperTap(ev);
|
|
}
|
|
mTouchState = TOUCH_STATE_REST;
|
|
mActivePointerId = INVALID_POINTER;
|
|
releaseVelocityTracker();
|
|
break;
|
|
|
|
case MotionEvent.ACTION_CANCEL:
|
|
if (mTouchState == TOUCH_STATE_SCROLLING) {
|
|
snapToDestination();
|
|
}
|
|
mTouchState = TOUCH_STATE_REST;
|
|
mActivePointerId = INVALID_POINTER;
|
|
releaseVelocityTracker();
|
|
break;
|
|
|
|
case MotionEvent.ACTION_POINTER_UP:
|
|
onSecondaryPointerUp(ev);
|
|
break;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
private void acquireVelocityTrackerAndAddMovement(MotionEvent ev) {
|
|
if (mVelocityTracker == null) {
|
|
mVelocityTracker = VelocityTracker.obtain();
|
|
}
|
|
mVelocityTracker.addMovement(ev);
|
|
}
|
|
|
|
private void releaseVelocityTracker() {
|
|
if (mVelocityTracker != null) {
|
|
mVelocityTracker.recycle();
|
|
mVelocityTracker = null;
|
|
}
|
|
}
|
|
|
|
private void onSecondaryPointerUp(MotionEvent ev) {
|
|
final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >>
|
|
MotionEvent.ACTION_POINTER_INDEX_SHIFT;
|
|
final int pointerId = ev.getPointerId(pointerIndex);
|
|
if (pointerId == mActivePointerId) {
|
|
// This was our active pointer going up. Choose a new
|
|
// active pointer and adjust accordingly.
|
|
// TODO: Make this decision more intelligent.
|
|
final int newPointerIndex = pointerIndex == 0 ? 1 : 0;
|
|
mLastMotionX = mDownMotionX = ev.getX(newPointerIndex);
|
|
mLastMotionY = ev.getY(newPointerIndex);
|
|
mActivePointerId = ev.getPointerId(newPointerIndex);
|
|
if (mVelocityTracker != null) {
|
|
mVelocityTracker.clear();
|
|
}
|
|
}
|
|
if (mTouchState == TOUCH_STATE_REST) {
|
|
onWallpaperTap(ev);
|
|
}
|
|
}
|
|
|
|
protected void onWallpaperTap(MotionEvent ev) {
|
|
}
|
|
|
|
@Override
|
|
public void requestChildFocus(View child, View focused) {
|
|
super.requestChildFocus(child, focused);
|
|
int page = indexOfChild(child);
|
|
if (page >= 0 && !isInTouchMode()) {
|
|
snapToPage(page);
|
|
}
|
|
}
|
|
|
|
protected int getChildIndexForRelativeOffset(int relativeOffset) {
|
|
final int childCount = getChildCount();
|
|
int left;
|
|
int right;
|
|
for (int i = 0; i < childCount; ++i) {
|
|
left = getRelativeChildOffset(i);
|
|
right = (left + getScaledMeasuredWidth(getChildAt(i)));
|
|
if (left <= relativeOffset && relativeOffset <= right) {
|
|
return i;
|
|
}
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
protected int getRelativeChildOffset(int index) {
|
|
return (getMeasuredWidth() - getChildAt(index).getMeasuredWidth()) / 2;
|
|
}
|
|
|
|
protected int getChildOffset(int index) {
|
|
if (getChildCount() == 0)
|
|
return 0;
|
|
|
|
int offset = getRelativeChildOffset(0);
|
|
for (int i = 0; i < index; ++i) {
|
|
offset += getScaledMeasuredWidth(getChildAt(i)) + mPageSpacing;
|
|
}
|
|
return offset;
|
|
}
|
|
|
|
protected int getScaledMeasuredWidth(View child) {
|
|
return (int) (child.getMeasuredWidth() * mLayoutScale + 0.5f);
|
|
}
|
|
|
|
int getPageNearestToCenterOfScreen() {
|
|
int minDistanceFromScreenCenter = getMeasuredWidth();
|
|
int minDistanceFromScreenCenterIndex = -1;
|
|
int screenCenter = mScrollX + (getMeasuredWidth() / 2);
|
|
final int childCount = getChildCount();
|
|
for (int i = 0; i < childCount; ++i) {
|
|
View layout = (View) getChildAt(i);
|
|
int childWidth = getScaledMeasuredWidth(layout);
|
|
int halfChildWidth = (childWidth / 2);
|
|
int childCenter = getChildOffset(i) + halfChildWidth;
|
|
int distanceFromScreenCenter = Math.abs(childCenter - screenCenter);
|
|
if (distanceFromScreenCenter < minDistanceFromScreenCenter) {
|
|
minDistanceFromScreenCenter = distanceFromScreenCenter;
|
|
minDistanceFromScreenCenterIndex = i;
|
|
}
|
|
}
|
|
return minDistanceFromScreenCenterIndex;
|
|
}
|
|
|
|
protected void snapToDestination() {
|
|
snapToPage(getPageNearestToCenterOfScreen(), PAGE_SNAP_ANIMATION_DURATION);
|
|
}
|
|
|
|
private static class ScrollInterpolator implements Interpolator {
|
|
public ScrollInterpolator() {
|
|
}
|
|
|
|
public float getInterpolation(float t) {
|
|
t -= 1.0f;
|
|
return t*t*t*t*t + 1;
|
|
}
|
|
}
|
|
|
|
// We want the duration of the page snap animation to be influenced by the distance that
|
|
// the screen has to travel, however, we don't want this duration to be effected in a
|
|
// purely linear fashion. Instead, we use this method to moderate the effect that the distance
|
|
// of travel has on the overall snap duration.
|
|
float distanceInfluenceForSnapDuration(float f) {
|
|
f -= 0.5f; // center the values about 0.
|
|
f *= 0.3f * Math.PI / 2.0f;
|
|
return (float) Math.sin(f);
|
|
}
|
|
|
|
protected void snapToPageWithVelocity(int whichPage, int velocity) {
|
|
whichPage = Math.max(0, Math.min(whichPage, getChildCount() - 1));
|
|
int halfScreenSize = getMeasuredWidth() / 2;
|
|
|
|
final int newX = getChildOffset(whichPage) - getRelativeChildOffset(whichPage);
|
|
int delta = newX - mUnboundedScrollX;
|
|
int duration = 0;
|
|
|
|
if (Math.abs(velocity) < MIN_FLING_VELOCITY) {
|
|
// If the velocity is low enough, then treat this more as an automatic page advance
|
|
// as opposed to an apparent physical response to flinging
|
|
snapToPage(whichPage, PAGE_SNAP_ANIMATION_DURATION);
|
|
return;
|
|
}
|
|
|
|
// Here we compute a "distance" that will be used in the computation of the overall
|
|
// snap duration. This is a function of the actual distance that needs to be traveled;
|
|
// we keep this value close to half screen size in order to reduce the variance in snap
|
|
// duration as a function of the distance the page needs to travel.
|
|
float distanceRatio = 1.0f * Math.abs(delta) / 2 * halfScreenSize;
|
|
float distance = halfScreenSize + halfScreenSize *
|
|
distanceInfluenceForSnapDuration(distanceRatio);
|
|
|
|
velocity = Math.abs(velocity);
|
|
velocity = Math.max(MINIMUM_SNAP_VELOCITY, velocity);
|
|
|
|
// we want the page's snap velocity to approximately match the velocity at which the
|
|
// user flings, so we scale the duration by a value near to the derivative of the scroll
|
|
// interpolator at zero, ie. 5. We use 6 to make it a little slower.
|
|
duration = 6 * Math.round(1000 * Math.abs(distance / velocity));
|
|
|
|
snapToPage(whichPage, delta, duration);
|
|
}
|
|
|
|
protected void snapToPage(int whichPage) {
|
|
snapToPage(whichPage, PAGE_SNAP_ANIMATION_DURATION);
|
|
}
|
|
|
|
protected void snapToPage(int whichPage, int duration) {
|
|
whichPage = Math.max(0, Math.min(whichPage, getPageCount() - 1));
|
|
|
|
int newX = getChildOffset(whichPage) - getRelativeChildOffset(whichPage);
|
|
final int sX = mUnboundedScrollX;
|
|
final int delta = newX - sX;
|
|
snapToPage(whichPage, delta, duration);
|
|
}
|
|
|
|
protected void snapToPage(int whichPage, int delta, int duration) {
|
|
mNextPage = whichPage;
|
|
|
|
View focusedChild = getFocusedChild();
|
|
if (focusedChild != null && whichPage != mCurrentPage &&
|
|
focusedChild == getChildAt(mCurrentPage)) {
|
|
focusedChild.clearFocus();
|
|
}
|
|
|
|
pageBeginMoving();
|
|
awakenScrollBars(duration);
|
|
if (duration == 0) {
|
|
duration = Math.abs(delta);
|
|
}
|
|
|
|
if (!mScroller.isFinished()) mScroller.abortAnimation();
|
|
mScroller.startScroll(mUnboundedScrollX, 0, delta, 0, duration);
|
|
|
|
// only load some associated pages
|
|
loadAssociatedPages(mNextPage);
|
|
notifyPageSwitchListener();
|
|
invalidate();
|
|
}
|
|
|
|
public void scrollLeft() {
|
|
if (mScroller.isFinished()) {
|
|
if (mCurrentPage > 0) snapToPage(mCurrentPage - 1);
|
|
} else {
|
|
if (mNextPage > 0) snapToPage(mNextPage - 1);
|
|
}
|
|
}
|
|
|
|
public void scrollRight() {
|
|
if (mScroller.isFinished()) {
|
|
if (mCurrentPage < getChildCount() -1) snapToPage(mCurrentPage + 1);
|
|
} else {
|
|
if (mNextPage < getChildCount() -1) snapToPage(mNextPage + 1);
|
|
}
|
|
}
|
|
|
|
public int getPageForView(View v) {
|
|
int result = -1;
|
|
if (v != null) {
|
|
ViewParent vp = v.getParent();
|
|
int count = getChildCount();
|
|
for (int i = 0; i < count; i++) {
|
|
if (vp == getChildAt(i)) {
|
|
return i;
|
|
}
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* @return True is long presses are still allowed for the current touch
|
|
*/
|
|
public boolean allowLongPress() {
|
|
return mAllowLongPress;
|
|
}
|
|
|
|
/**
|
|
* Set true to allow long-press events to be triggered, usually checked by
|
|
* {@link Launcher} to accept or block dpad-initiated long-presses.
|
|
*/
|
|
public void setAllowLongPress(boolean allowLongPress) {
|
|
mAllowLongPress = allowLongPress;
|
|
}
|
|
|
|
public static class SavedState extends BaseSavedState {
|
|
int currentPage = -1;
|
|
|
|
SavedState(Parcelable superState) {
|
|
super(superState);
|
|
}
|
|
|
|
private SavedState(Parcel in) {
|
|
super(in);
|
|
currentPage = in.readInt();
|
|
}
|
|
|
|
@Override
|
|
public void writeToParcel(Parcel out, int flags) {
|
|
super.writeToParcel(out, flags);
|
|
out.writeInt(currentPage);
|
|
}
|
|
|
|
public static final Parcelable.Creator<SavedState> CREATOR =
|
|
new Parcelable.Creator<SavedState>() {
|
|
public SavedState createFromParcel(Parcel in) {
|
|
return new SavedState(in);
|
|
}
|
|
|
|
public SavedState[] newArray(int size) {
|
|
return new SavedState[size];
|
|
}
|
|
};
|
|
}
|
|
|
|
public void loadAssociatedPages(int page) {
|
|
if (mContentIsRefreshable) {
|
|
final int count = getChildCount();
|
|
if (page < count) {
|
|
int lowerPageBound = getAssociatedLowerPageBound(page);
|
|
int upperPageBound = getAssociatedUpperPageBound(page);
|
|
for (int i = 0; i < count; ++i) {
|
|
final ViewGroup layout = (ViewGroup) getChildAt(i);
|
|
final int childCount = layout.getChildCount();
|
|
if (lowerPageBound <= i && i <= upperPageBound) {
|
|
if (mDirtyPageContent.get(i)) {
|
|
syncPageItems(i);
|
|
mDirtyPageContent.set(i, false);
|
|
}
|
|
} else {
|
|
if (childCount > 0) {
|
|
layout.removeAllViews();
|
|
}
|
|
mDirtyPageContent.set(i, true);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
protected int getAssociatedLowerPageBound(int page) {
|
|
return Math.max(0, page - 1);
|
|
}
|
|
protected int getAssociatedUpperPageBound(int page) {
|
|
final int count = getChildCount();
|
|
return Math.min(page + 1, count - 1);
|
|
}
|
|
|
|
protected void startChoiceMode(int mode, ActionMode.Callback callback) {
|
|
if (isChoiceMode(CHOICE_MODE_NONE)) {
|
|
mChoiceMode = mode;
|
|
mActionMode = startActionMode(callback);
|
|
}
|
|
}
|
|
|
|
public void endChoiceMode() {
|
|
if (!isChoiceMode(CHOICE_MODE_NONE)) {
|
|
mChoiceMode = CHOICE_MODE_NONE;
|
|
resetCheckedGrandchildren();
|
|
if (mActionMode != null) mActionMode.finish();
|
|
mActionMode = null;
|
|
}
|
|
}
|
|
|
|
protected boolean isChoiceMode(int mode) {
|
|
return mChoiceMode == mode;
|
|
}
|
|
|
|
protected ArrayList<Checkable> getCheckedGrandchildren() {
|
|
ArrayList<Checkable> checked = new ArrayList<Checkable>();
|
|
final int childCount = getChildCount();
|
|
for (int i = 0; i < childCount; ++i) {
|
|
final ViewGroup layout = (ViewGroup) getChildAt(i);
|
|
final int grandChildCount = layout.getChildCount();
|
|
for (int j = 0; j < grandChildCount; ++j) {
|
|
final View v = layout.getChildAt(j);
|
|
if (v instanceof Checkable && ((Checkable) v).isChecked()) {
|
|
checked.add((Checkable) v);
|
|
}
|
|
}
|
|
}
|
|
return checked;
|
|
}
|
|
|
|
/**
|
|
* If in CHOICE_MODE_SINGLE and an item is checked, returns that item.
|
|
* Otherwise, returns null.
|
|
*/
|
|
protected Checkable getSingleCheckedGrandchild() {
|
|
if (mChoiceMode == CHOICE_MODE_SINGLE) {
|
|
final int childCount = getChildCount();
|
|
for (int i = 0; i < childCount; ++i) {
|
|
final ViewGroup layout = (ViewGroup) getChildAt(i);
|
|
final int grandChildCount = layout.getChildCount();
|
|
for (int j = 0; j < grandChildCount; ++j) {
|
|
final View v = layout.getChildAt(j);
|
|
if (v instanceof Checkable && ((Checkable) v).isChecked()) {
|
|
return (Checkable) v;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return null;
|
|
}
|
|
|
|
public Object getChosenItem() {
|
|
View checkedView = (View) getSingleCheckedGrandchild();
|
|
if (checkedView != null) {
|
|
return checkedView.getTag();
|
|
}
|
|
return null;
|
|
}
|
|
|
|
protected void resetCheckedGrandchildren() {
|
|
// loop through children, and set all of their children to _not_ be checked
|
|
final ArrayList<Checkable> checked = getCheckedGrandchildren();
|
|
for (int i = 0; i < checked.size(); ++i) {
|
|
final Checkable c = checked.get(i);
|
|
c.setChecked(false);
|
|
}
|
|
}
|
|
|
|
public void setRestorePage(int restorePage) {
|
|
mRestorePage = restorePage;
|
|
}
|
|
|
|
/**
|
|
* This method is called ONLY to synchronize the number of pages that the paged view has.
|
|
* To actually fill the pages with information, implement syncPageItems() below. It is
|
|
* guaranteed that syncPageItems() will be called for a particular page before it is shown,
|
|
* and therefore, individual page items do not need to be updated in this method.
|
|
*/
|
|
public abstract void syncPages();
|
|
|
|
/**
|
|
* This method is called to synchronize the items that are on a particular page. If views on
|
|
* the page can be reused, then they should be updated within this method.
|
|
*/
|
|
public abstract void syncPageItems(int page);
|
|
|
|
public void invalidatePageData() {
|
|
if (mContentIsRefreshable) {
|
|
// Update all the pages
|
|
syncPages();
|
|
|
|
// Mark each of the pages as dirty
|
|
final int count = getChildCount();
|
|
mDirtyPageContent.clear();
|
|
for (int i = 0; i < count; ++i) {
|
|
mDirtyPageContent.add(true);
|
|
}
|
|
|
|
// Use the restore page if necessary
|
|
if (mRestorePage > -1) {
|
|
mCurrentPage = mRestorePage;
|
|
mRestorePage = -1;
|
|
}
|
|
|
|
// Load any pages that are necessary for the current window of views
|
|
loadAssociatedPages(mCurrentPage);
|
|
mDirtyPageAlpha = true;
|
|
updateAdjacentPagesAlpha();
|
|
requestLayout();
|
|
}
|
|
}
|
|
}
|