Android TintResources Leak

　　在使用Android WebView的时候，可能会造成Activity的内存泄漏，这个是Android的Bug,目前发现在WebView内部在使用TintResources时会发生内存泄漏，但是在appcompat-v7:23.2.1中已经修复了这个问题。所以当发生WebView的Context内存泄漏时,如果泄漏引用是来自TickResources时，可以将appcompat-v7包换成23.2.1或以上就可以解决了。具体原因我们可以来下源码：

　　appcompat-v7 23.2.0 中的TintResources:

 public class TintResources extends Resources {
     private final Context mContext;

     public TintResources(@NonNull final Context context, @NonNull final Resources res) {
         super(res.getAssets(), res.getDisplayMetrics(), res.getConfiguration());
         mContext = context;
     }

     /**
      * We intercept this call so that we tint the result (if applicable). This is needed for
      * things like {@link android.graphics.drawable.DrawableContainer}s which can retrieve
      * their children via this method.
      */
     @Override
     public Drawable getDrawable(int id) throws NotFoundException {
         return AppCompatDrawableManager.get().onDrawableLoadedFromResources(mContext, this, id);
     }

     final Drawable superGetDrawable(int id) {
         return super.getDrawable(id);
     }
 }

appcompat-v7 23.2.1中的TintResources:

 public class TintResources extends Resources {
     private final WeakReference<Context> mContextRef;

     public TintResources(@NonNull final Context context, @NonNull final Resources res) {
         super(res.getAssets(), res.getDisplayMetrics(), res.getConfiguration());
         mContextRef = new WeakReference<>(context);
     }

     /**
      * We intercept this call so that we tint the result (if applicable). This is needed for
      * things like {@link android.graphics.drawable.DrawableContainer}s which can retrieve
      * their children via this method.
      */
     @Override
     public Drawable getDrawable(int id) throws NotFoundException {
         final Context context = mContextRef.get();
         if (context != null) {
             return AppCompatDrawableManager.get().onDrawableLoadedFromResources(context, this, id);
         } else {
             return super.getDrawable(id);
         }
     }

     final Drawable superGetDrawable(int id) {
         return super.getDrawable(id);
     }
 }

可以很清楚的看的23.2.1版本只是将Context的强引用改成了弱引用来避免内存泄漏。