Default setup wizard to use PIN

- Added "Screen lock options" button in PIN screen, controlled by
  extra EXTRA_SHOW_OPTIONS_BUTTON, which will create a dialog to ask
  the user to choose another screen lock type.
- Extracted ScreenLockType enum and ChooseLockGenericController that
  can be shared by ChooseLockGeneric and the dialog
  ChooseLockTypeDialogFragment.
- The intent extra EXTRA_SHOW_OPTIONS_BUTTON will be set if
  ChooseLockGeneric screen starts ChooseLockPassword /
  ChooseLockPattern without asking the user. (Although the extra is
  ignored by ChooseLockPattern currently)
- Fix layout alignment for the password entry field to remove the
  extra 4dp padding on the sides.

Test: cd tests/robotests && mma
Bug: 35442933
Bug: 38002299
Change-Id: I877fbe08a0c05bb97175e1cbf0260ea6dbda22e2

src/com/android/settings/password/ChooseLockGenericController.java

@@ -0,0 +1,158 @@
+/*
+ * Copyright (C) 2017 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.password;
+
+import android.app.admin.DevicePolicyManager;
+import android.content.Context;
+import android.os.UserHandle;
+import android.support.annotation.NonNull;
+import android.support.annotation.VisibleForTesting;
+
+import com.android.settings.R;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * A controller for ChooseLockGeneric, and other similar classes which shows a list of possible
+ * screen locks for the user to choose from.
+ */
+public class ChooseLockGenericController {
+
+    private final Context mContext;
+    private final int mUserId;
+    private ManagedLockPasswordProvider mManagedPasswordProvider;
+    private DevicePolicyManager mDpm;
+
+    public ChooseLockGenericController(Context context, int userId) {
+        this(
+                context,
+                userId,
+                context.getSystemService(DevicePolicyManager.class),
+                ManagedLockPasswordProvider.get(context, userId));
+    }
+
+    @VisibleForTesting
+    ChooseLockGenericController(
+            Context context,
+            int userId,
+            DevicePolicyManager dpm,
+            ManagedLockPasswordProvider managedLockPasswordProvider) {
+        mContext = context;
+        mUserId = userId;
+        mManagedPasswordProvider = managedLockPasswordProvider;
+        mDpm = dpm;
+    }
+
+    /**
+     * @return The higher quality of either the specified {@code quality} or the quality required
+     *         by {@link DevicePolicyManager#getPasswordQuality}.
+     */
+    public int upgradeQuality(int quality) {
+        // Compare min allowed password quality
+        return Math.max(quality, mDpm.getPasswordQuality(null, mUserId));
+    }
+
+    /**
+     * Whether the given screen lock type should be visible in the given context.
+     */
+    public boolean isScreenLockVisible(ScreenLockType type) {
+        switch (type) {
+            case NONE:
+                return !mContext.getResources().getBoolean(R.bool.config_hide_none_security_option);
+            case SWIPE:
+                return !mContext.getResources().getBoolean(R.bool.config_hide_swipe_security_option)
+                    // Swipe doesn't make sense for profiles.
+                    && mUserId == UserHandle.myUserId();
+            case MANAGED:
+                return mManagedPasswordProvider.isManagedPasswordChoosable();
+        }
+        return true;
+    }
+
+    /**
+     * Whether screen lock with {@code type} should be enabled.
+     *
+     * @param type The screen lock type.
+     * @param quality The minimum required quality. This can either be requirement by device policy
+     *                manager or because some flow only makes sense with secure lock screens.
+     */
+    public boolean isScreenLockEnabled(ScreenLockType type, int quality) {
+        return type.maxQuality >= quality;
+    }
+
+    /**
+     * Whether screen lock with {@code type} is disabled by device policy admin.
+     *
+     * @param type The screen lock type.
+     * @param adminEnforcedQuality The minimum quality that the admin enforces.
+     */
+    public boolean isScreenLockDisabledByAdmin(ScreenLockType type, int adminEnforcedQuality) {
+        boolean disabledByAdmin = type.maxQuality < adminEnforcedQuality;
+        if (type == ScreenLockType.MANAGED) {
+            disabledByAdmin = disabledByAdmin
+                    || !mManagedPasswordProvider.isManagedPasswordChoosable();
+        }
+        return disabledByAdmin;
+    }
+
+    /**
+     * User friendly title for the given screen lock type.
+     */
+    public CharSequence getTitle(ScreenLockType type) {
+        switch (type) {
+            case NONE:
+                return mContext.getText(R.string.unlock_set_unlock_off_title);
+            case SWIPE:
+                return mContext.getText(R.string.unlock_set_unlock_none_title);
+            case PATTERN:
+                return mContext.getText(R.string.unlock_set_unlock_pattern_title);
+            case PIN:
+                return mContext.getText(R.string.unlock_set_unlock_pin_title);
+            case PASSWORD:
+                return mContext.getText(R.string.unlock_set_unlock_password_title);
+            case MANAGED:
+                return mManagedPasswordProvider.getPickerOptionTitle(false);
+        }
+        return null;
+    }
+
+    /**
+     * Gets a list of screen locks that should be visible for the given quality. The returned list
+     * is ordered in the natural order of the enum (the order those enums were defined).
+     *
+     * @param quality The minimum quality required in the context of the current flow. This should
+     *                be one of the constants defined in
+     *                {@code DevicePolicyManager#PASSWORD_QUALITY_*}.
+     * @param includeDisabled Whether to include screen locks disabled by {@code quality}
+     *                        requirements in the returned list.
+     */
+    @NonNull
+    public List<ScreenLockType> getVisibleScreenLockTypes(int quality, boolean includeDisabled) {
+        int upgradedQuality = upgradeQuality(quality);
+        List<ScreenLockType> locks = new ArrayList<>();
+        // EnumSet's iterator guarantees the natural order of the enums
+        for (ScreenLockType lock : ScreenLockType.values()) {
+            if (isScreenLockVisible(lock)) {
+                if (includeDisabled || isScreenLockEnabled(lock, upgradedQuality)) {
+                    locks.add(lock);
+                }
+            }
+        }
+        return locks;
+    }
+}