1 /*
2  * Copyright (C) 2015 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 android.support.v7.widget;
18 
19 import static android.support.annotation.RestrictTo.Scope.LIBRARY_GROUP;
20 
21 import android.content.Context;
22 import android.content.res.Resources;
23 import android.graphics.drawable.Drawable;
24 import android.os.Build;
25 import android.support.annotation.NonNull;
26 import android.support.annotation.RestrictTo;
27 import android.support.v7.app.AppCompatDelegate;
28 
29 import java.lang.ref.WeakReference;
30 
31 /**
32  * This class allows us to intercept calls so that we can tint resources (if applicable), and
33  * inflate vector resources from within drawable containers pre-L.
34  *
35  * @hide
36  */
37 @RestrictTo(LIBRARY_GROUP)
38 public class VectorEnabledTintResources extends Resources {
39 
shouldBeUsed()40     public static boolean shouldBeUsed() {
41         return AppCompatDelegate.isCompatVectorFromResourcesEnabled()
42                 && Build.VERSION.SDK_INT <= MAX_SDK_WHERE_REQUIRED;
43     }
44 
45     /**
46      * The maximum API level where this class is needed.
47      */
48     public static final int MAX_SDK_WHERE_REQUIRED = 20;
49 
50     private final WeakReference<Context> mContextRef;
51 
VectorEnabledTintResources(@onNull final Context context, @NonNull final Resources res)52     public VectorEnabledTintResources(@NonNull final Context context,
53             @NonNull final Resources res) {
54         super(res.getAssets(), res.getDisplayMetrics(), res.getConfiguration());
55         mContextRef = new WeakReference<>(context);
56     }
57 
58     /**
59      * We intercept this call so that we tint the result (if applicable). This is needed for
60      * things like {@link android.graphics.drawable.DrawableContainer}s which can retrieve
61      * their children via this method.
62      */
63     @Override
getDrawable(int id)64     public Drawable getDrawable(int id) throws NotFoundException {
65         final Context context = mContextRef.get();
66         if (context != null) {
67             return AppCompatDrawableManager.get().onDrawableLoadedFromResources(context, this, id);
68         } else {
69             return super.getDrawable(id);
70         }
71     }
72 
superGetDrawable(int id)73     final Drawable superGetDrawable(int id) {
74         return super.getDrawable(id);
75     }
76 }