Canvas：尝试使用回收的位图 android.graphics.Bitmap

Question

11-24 23:19:18.434: ERROR/AndroidRuntime(12660): Uncaught handler: thread main exiting due to uncaught exception
11-24 23:19:18.684: ERROR/AndroidRuntime(12660): java.lang.RuntimeException: Canvas: trying to use a recycled bitmap android.graphics.Bitmap@4384c218
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.graphics.Canvas.throwIfRecycled(Canvas.java:955)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.graphics.Canvas.drawBitmap(Canvas.java:1044)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.graphics.drawable.BitmapDrawable.draw(BitmapDrawable.java:291)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.widget.ImageView.onDraw(ImageView.java:908)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.View.draw(View.java:6283)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.drawChild(ViewGroup.java:1581)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1311)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.drawChild(ViewGroup.java:1579)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1311)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.View.draw(View.java:6286)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.drawChild(ViewGroup.java:1581)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1311)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.widget.AbsListView.dispatchDraw(AbsListView.java:1323)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.widget.ListView.dispatchDraw(ListView.java:2933)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.View.draw(View.java:6389)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at         android.widget.AbsListView.draw(AbsListView.java:2142)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.drawChild(ViewGroup.java:1581)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1311)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.drawChild(ViewGroup.java:1579)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1311)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at     android.view.View.draw(View.java:6286)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.drawChild(ViewGroup.java:1581)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1311)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.View.draw(View.java:6286)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.widget.FrameLayout.draw(FrameLayout.java:352)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewGroup.drawChild(ViewGroup.java:1581)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at     android.view.ViewGroup.dispatchDraw(ViewGroup.java:1311)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.View.draw(View.java:6286)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.widget.FrameLayout.draw(FrameLayout.java:352)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at com.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:1928)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewRoot.draw(ViewRoot.java:1454)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewRoot.performTraversals(ViewRoot.java:1174)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1774)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.os.Looper.loop(Looper.java:123)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at android.app.ActivityThread.main(ActivityThread.java:4321)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at java.lang.reflect.Method.invokeNative(Native Method)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at java.lang.reflect.Method.invoke(Method.java:521)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
11-24 23:19:18.684: ERROR/AndroidRuntime(12660):     at dalvik.system.NativeStart.main(Native Method)

我使用 SoftReference 实现了图像缓存，并使用图像缓存中的位图设置了 ImageView。

我不使用 Bitmap.recycle() 并在将位图设置为 ImageView 之前检查 Bitmap.isRcycled() 。

我不明白为什么画布是用回收的位图绘制的。 这种情况很少发生，但确实发生过。

有什么建议吗？ 谢谢！

Answer 1

如果有人到达这里并且正在努力找出哪个位图被回收（就像我一样），这就是我最终解决此问题的方法：
1）我放置了一个全局 Thread.setDefaultUncaughtExceptionHandler 来转储堆（实际上我已经用它来诊断 OOM 错误）。处理程序内的代码是这样的：

File f = new File(Environment.getExternalStorageDirectory(),"oom-error.hprof");
String path = f.getAbsolutePath();
// force a few GC before dumping stuff
System.gc();
System.gc();    
Debug.dumpHprofData(path);

2) 使用 这篇很棒的文章，您可以学习如何使用 MAT。

3）在MAT内部，我首先通过“Bitmap”正则表达式过滤类，然后查找位图参考id（在OP情况下：“4384c218”）。这将使您很好地了解哪个视图保存了这个回收的位图，您可以开始考虑它的解决方案。
（就我而言，我从公共缓存中回收图像，其中一些是可绘制对象，也用于 XML 布局，并且应该“固定”到缓存直到 OnDestroy）。

Answer 2

当其中一个活动正在回收其位图时，您不应将相同的图像资源用于不同的活动。

如果您遇到这种情况，请更改其中一项活动的图像资源。

Answer 3

同样的问题，但现在我已经解决了。当重新加载 png 或其他时尝试这样：

BitmapFactory.decodeStream(getResources().openRawResource(R.drawable.png1));

我必须知道 png1 何时被回收，如果没有，您也可以尝试捕获 RuntimeException 异常。