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      1 /*
      2  * Copyright (C) 2013 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package com.android.settings.accessibility;
     18 
     19 import android.content.Context;
     20 import android.graphics.Color;
     21 import android.graphics.drawable.ColorDrawable;
     22 import android.graphics.drawable.Drawable;
     23 import android.support.v7.preference.PreferenceViewHolder;
     24 import android.text.TextUtils;
     25 import android.util.AttributeSet;
     26 import android.view.View;
     27 import android.widget.ImageView;
     28 import android.widget.TextView;
     29 
     30 import com.android.settings.R;
     31 
     32 /**
     33  * Grid preference that allows the user to pick a color from a predefined set of
     34  * colors. Optionally shows a preview in the preference item.
     35  */
     36 public class ColorPreference extends ListDialogPreference {
     37     private ColorDrawable mPreviewColor;
     38     private boolean mPreviewEnabled;
     39 
     40     public ColorPreference(Context context, AttributeSet attrs) {
     41         super(context, attrs);
     42 
     43         setDialogLayoutResource(R.layout.grid_picker_dialog);
     44         setListItemLayoutResource(R.layout.color_picker_item);
     45     }
     46 
     47     /**
     48      * @param enabled whether to show a preview in the preference item
     49      */
     50     public void setPreviewEnabled(boolean enabled) {
     51         if (mPreviewEnabled != enabled) {
     52             mPreviewEnabled = enabled;
     53 
     54             if (enabled) {
     55                 setWidgetLayoutResource(R.layout.preference_color);
     56             } else {
     57                 setWidgetLayoutResource(0);
     58             }
     59         }
     60     }
     61 
     62     @Override
     63     public boolean shouldDisableDependents() {
     64         return Color.alpha(getValue()) == 0 || super.shouldDisableDependents();
     65     }
     66 
     67     @Override
     68     protected CharSequence getTitleAt(int index) {
     69         final CharSequence title = super.getTitleAt(index);
     70         if (title != null) {
     71             return title;
     72         }
     73 
     74         // If no title was supplied, format title using RGB values.
     75         final int value = getValueAt(index);
     76         final int r = Color.red(value);
     77         final int g = Color.green(value);
     78         final int b = Color.blue(value);
     79         return getContext().getString(R.string.color_custom, r, g, b);
     80     }
     81 
     82     @Override
     83     public void onBindViewHolder(PreferenceViewHolder view) {
     84         super.onBindViewHolder(view);
     85 
     86         if (mPreviewEnabled) {
     87             final ImageView previewImage = (ImageView) view.findViewById(R.id.color_preview);
     88             final int argb = getValue();
     89             if (Color.alpha(argb) < 255) {
     90                 previewImage.setBackgroundResource(R.drawable.transparency_tileable);
     91             } else {
     92                 previewImage.setBackground(null);
     93             }
     94 
     95             if (mPreviewColor == null) {
     96                 mPreviewColor = new ColorDrawable(argb);
     97                 previewImage.setImageDrawable(mPreviewColor);
     98             } else {
     99                 mPreviewColor.setColor(argb);
    100             }
    101 
    102             final CharSequence summary = getSummary();
    103             if (!TextUtils.isEmpty(summary)) {
    104                 previewImage.setContentDescription(summary);
    105             } else {
    106                 previewImage.setContentDescription(null);
    107             }
    108 
    109             previewImage.setAlpha(isEnabled() ? 1f : 0.2f);
    110         }
    111     }
    112 
    113     @Override
    114     protected void onBindListItem(View view, int index) {
    115         final int argb = getValueAt(index);
    116         final int alpha = Color.alpha(argb);
    117 
    118         final ImageView swatch = (ImageView) view.findViewById(R.id.color_swatch);
    119         if (alpha < 255) {
    120             swatch.setBackgroundResource(R.drawable.transparency_tileable);
    121         } else {
    122             swatch.setBackground(null);
    123         }
    124 
    125         final Drawable foreground = swatch.getDrawable();
    126         if (foreground instanceof ColorDrawable) {
    127             ((ColorDrawable) foreground).setColor(argb);
    128         } else {
    129             swatch.setImageDrawable(new ColorDrawable(argb));
    130         }
    131 
    132         final CharSequence title = getTitleAt(index);
    133         if (title != null) {
    134             final TextView summary = (TextView) view.findViewById(R.id.summary);
    135             summary.setText(title);
    136         }
    137     }
    138 }
    139