1 /*
2  * Copyright (C) 2014 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;
18 
19 import android.annotation.Nullable;
20 import android.content.Context;
21 import android.graphics.drawable.Drawable;
22 import android.support.v7.preference.Preference;
23 import android.support.v7.preference.PreferenceViewHolder;
24 import android.text.TextUtils;
25 import android.util.AttributeSet;
26 import android.widget.TextView;
27 
28 import com.android.settingslib.RestrictedPreference;
29 
30 /**
31  * A preference item that can dim the icon when it's disabled, either directly or because its parent
32  * is disabled.
33  */
34 public class DimmableIconPreference extends RestrictedPreference {
35     private static final int ICON_ALPHA_ENABLED = 255;
36     private static final int ICON_ALPHA_DISABLED = 102;
37 
38     private final CharSequence mContentDescription;
39 
DimmableIconPreference(Context context)40     public DimmableIconPreference(Context context) {
41         this(context, (AttributeSet) null);
42     }
43 
DimmableIconPreference(Context context, AttributeSet attrs)44     public DimmableIconPreference(Context context, AttributeSet attrs) {
45         super(context, attrs);
46         mContentDescription = null;
47         useAdminDisabledSummary(true);
48     }
49 
DimmableIconPreference(Context context, @Nullable CharSequence contentDescription)50     public DimmableIconPreference(Context context, @Nullable CharSequence contentDescription) {
51         super(context);
52         mContentDescription = contentDescription;
53         useAdminDisabledSummary(true);
54     }
55 
dimIcon(boolean dimmed)56     private void dimIcon(boolean dimmed) {
57         Drawable icon = getIcon();
58         if (icon != null) {
59             icon.mutate().setAlpha(dimmed ? ICON_ALPHA_DISABLED : ICON_ALPHA_ENABLED);
60             setIcon(icon);
61         }
62     }
63 
64     @Override
onBindViewHolder(PreferenceViewHolder view)65     public void onBindViewHolder(PreferenceViewHolder view) {
66         super.onBindViewHolder(view);
67         if (!TextUtils.isEmpty(mContentDescription)) {
68             final TextView titleView = (TextView) view.findViewById(android.R.id.title);
69             titleView.setContentDescription(mContentDescription);
70         }
71         dimIcon(!isEnabled());
72     }
73 }
74