Canvas:尝试使用可回收的位图android

Question

我一直有这个问题,我不知道该怎么办.

我已经使用了这个库,当我得到裁剪后的图像时,我将它保存在一个静态变量中并转到下一个活动.当我到达下一个活动时,我引用该静态变量来获取位图并尝试将其缩小.但它给了我错误.

这就是我在做什么.

public void buttonCropClick(View view) throws IOException
{
    imageView.setDrawingCacheEnabled(true);
    imageView.buildDrawingCache(true);
    Snapshot.CroppedBitmap = imageView.getDrawingCache(true);
    imageView.setDrawingCacheEnabled(false);
    startActivity(new Intent(this,RecommendationInfo.class));
}

在RecommendationInfo类中,我得到以下行中的位图Snapshot.CroppedBitmap = imageView.getDrawingCache(true);然后我将此位图保存在我在下一个活动中引用的静态变量中并将其传递给以下函数.

public static Bitmap scaleDown(Bitmap realImage,boolean filter) {

    float maxImageSize = HeightToSet;
    float ratio = Math.min(
            (float) maxImageSize / realImage.getWidth(),
            (float) maxImageSize / realImage.getHeight());
    int width = Math.round((float) ratio * realImage.getWidth());
    int height = Math.round((float) ratio * realImage.getHeight());

    // Error here
    Bitmap newBitmap = Bitmap.createScaledBitmap(realImage, width,height, filter);
    return newBitmap;
}

我已经试过打电话了bitmap.recycle().为什么我遇到这个问题我该怎么做才能解决它？这是我的logcat.

07-14 03:09:43.713: E/AndroidRuntime(19653): FATAL EXCEPTION: main
07-14 03:09:43.713: E/AndroidRuntime(19653): java.lang.RuntimeException: Canvas: trying to use a recycled bitmap android.graphics.Bitmap@4059b8b8
07-14 03:09:43.713: E/AndroidRuntime(19653):    at android.graphics.Canvas.throwIfRecycled(Canvas.java:955)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at android.graphics.Canvas.drawBitmap(Canvas.java:1012)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at android.graphics.Bitmap.createBitmap(Bitmap.java:462)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at android.graphics.Bitmap.createScaledBitmap(Bitmap.java:349)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at com.example.Libraries.Snapshot.scaleDown(Snapshot.java:42)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at com.example.androidtestproject.RecommendationInfo.SetRecommendationValues(RecommendationInfo.java:195)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at com.example.androidtestproject.RecommendationInfo.access$5(RecommendationInfo.java:183)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at com.example.androidtestproject.RecommendationInfo$1.onClick(RecommendationInfo.java:154)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at android.view.View.performClick(View.java:2552)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at android.view.View$PerformClick.run(View.java:9229)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at android.os.Handler.handleCallback(Handler.java:587)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at android.os.Handler.dispatchMessage(Handler.java:92)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at android.os.Looper.loop(Looper.java:138)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at android.app.ActivityThread.main(ActivityThread.java:3701)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at java.lang.reflect.Method.invokeNative(Native Method)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at java.lang.reflect.Method.invoke(Method.java:507)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:878)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:636)
07-14 03:09:43.713: E/AndroidRuntime(19653):    at dalvik.system.NativeStart.main(Native Method)
07-14 03:09:45.515: E/TAG(20039): End of input at character 0 of 

Answer 1

在将位图传递给静态变量之前复制该位图.

Snapshot.CroppedBitmap = imageView.getDrawingCache(true);

至

Snapshot.CroppedBitmap = Bitmap.createBitmap(imageView.getDrawingCache(true));

当不再需要时,imageView很可能正在回收其绘图缓存作为良好实践.通过将其复制出来,您可以继续引用ImageView的位图.只需制作一份你可以自己管理的副本!