Introduce SwitchBar widget

- SwitchBar is a LinearLayout that containts a TextView and a Switch and
is intended to replace all Switches that are put in the ActionBar as a
custom view
- use the new SwitchBar for WifiSetting only for now (a later CL will
take care of all the other Setting that are using a Switch in the
ActionBar)

Related to bug #14898161 On/Off switches must move down from Action Bar

Change-Id: I5e98dbe995bba8f440d08459e09ca3ac09d3464b

src/com/android/settings/widget/SwitchBar.java

@@ -0,0 +1,128 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.widget;
+
+import android.content.Context;
+import android.transition.TransitionManager;
+import android.util.AttributeSet;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.CompoundButton;
+import android.widget.LinearLayout;
+
+import android.widget.Switch;
+import android.widget.TextView;
+import com.android.settings.R;
+
+import java.util.ArrayList;
+
+public class SwitchBar extends LinearLayout implements CompoundButton.OnCheckedChangeListener {
+
+    private Switch mSwitch;
+    private TextView mTextView;
+
+    private ArrayList<OnSwitchChangeListener> mSwitchChangeListeners =
+            new ArrayList<OnSwitchChangeListener>();
+
+    public static interface OnSwitchChangeListener {
+        /**
+         * Called when the checked state of the Switch has changed.
+         *
+         * @param switchView The Switch view whose state has changed.
+         * @param isChecked  The new checked state of switchView.
+         */
+        void onSwitchChanged(Switch switchView, boolean isChecked);
+    }
+
+    public SwitchBar(Context context) {
+        this(context, null);
+    }
+
+    public SwitchBar(Context context, AttributeSet attrs) {
+        this(context, attrs, 0);
+    }
+
+    public SwitchBar(Context context, AttributeSet attrs, int defStyleAttr) {
+        this(context, attrs, defStyleAttr, 0);
+    }
+
+    public SwitchBar(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
+        super(context, attrs, defStyleAttr, defStyleRes);
+
+        LayoutInflater.from(context).inflate(R.layout.switch_bar, this);
+
+        mTextView = (TextView) findViewById(R.id.switch_text);
+        mTextView.setText(R.string.switch_off_text);
+
+        mSwitch = (Switch) findViewById(R.id.switch_widget);
+        mSwitch.setOnCheckedChangeListener(this);
+
+        addOnSwitchChangeListener(new OnSwitchChangeListener() {
+            @Override
+            public void onSwitchChanged(Switch switchView, boolean isChecked) {
+                mTextView.setText(isChecked ? R.string.switch_on_text : R.string.switch_off_text);
+            }
+        });
+
+        mSwitch.setTrackResource(R.drawable.switch_track);
+        mSwitch.setThumbResource(R.drawable.switch_inner);
+
+        // Default is hide
+        setVisibility(View.GONE);
+    }
+
+    public Switch getSwitch() {
+        return mSwitch;
+    }
+
+    public void show() {
+        TransitionManager.beginDelayedTransition((ViewGroup) getParent());
+        setVisibility(View.VISIBLE);
+    }
+
+    public void hide() {
+        TransitionManager.beginDelayedTransition((ViewGroup) getParent());
+        setVisibility(View.GONE);
+    }
+
+    public boolean isShowing() {
+        return (getVisibility() == View.VISIBLE);
+    }
+
+    @Override
+    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
+        final int count = mSwitchChangeListeners.size();
+        for (int n = 0; n < count; n++) {
+            mSwitchChangeListeners.get(n).onSwitchChanged(mSwitch,isChecked);
+        }
+    }
+
+    public void addOnSwitchChangeListener(OnSwitchChangeListener listener) {
+        if (mSwitchChangeListeners.contains(listener)) {
+            throw new IllegalStateException("Cannot add twice the same OnSwitchChangeListener");
+        }
+        mSwitchChangeListeners.add(listener);
+    }
+
+    public void removeOnSwitchChangeListener(OnSwitchChangeListener listener) {
+        if (!mSwitchChangeListeners.contains(listener)) {
+            throw new IllegalStateException("Cannot remove OnSwitchChangeListener");
+        }
+        mSwitchChangeListeners.remove(listener);
+    }
+}