在销毁时释放特定活动的内存

Question

我有一个启动器Activity加载和调整大位图的大小,因为它是打开时的背景.

每当按下后退按钮时,Activity就是destroyed.但我认为记忆尚未公布.

当我打开应用程序时,点击后退按钮再次打开它(反复),我会得到一个OutOfMemoryError.

我这个新手的问题,对不起,但我不知道我怎么释放每当记忆Activity是destroyed？

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_welcome);

    //MARK - movingBackgroundImageView
    movingBackgroundImageView = (ImageView) findViewById(R.id.movingBackgroundImageView);
    movingBackgroundImageView.setColorFilter(Color.argb(255, 255, 255, 255));
    movingBackgroundImageView.setScaleType(ImageView.ScaleType.MATRIX);
    movingBackgroundImageView.setAlpha(0.28f);

    prepareBackgroundAnimation();
}

private void prepareBackgroundAnimation() {

    DisplayMetrics displaymetrics = new DisplayMetrics();
    getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);

    screenWidth = displaymetrics.widthPixels;
    screenHeight = displaymetrics.heightPixels;

    movingImageHeight = displaymetrics.heightPixels;
    movingImageWidth = 1920.0 / 1080.0 * movingImageHeight;

    bitmapImage = BitmapFactory.decodeResource(this.getResources(), R.drawable.moving_background_image);
    scaledBitmap = bitmapImage.createScaledBitmap(bitmapImage, (int) movingImageWidth, (int) movingImageHeight, false);
    movingBackgroundImageView.setImageBitmap(scaledBitmap);

    backgroundImageInBeginning = true;

    movingBackgroundImageView.post(new Runnable() {
        @Override
        public void run() {
            movingBackgroundImageView.setImageMatrix(matrix);
            moveBackground();
        }
    });
}

12-22 13:44:49.549 30885-30885 /？E/AndroidRuntime:FATAL EXCEPTION:main进程:id.testingapp.android.TestingApp,PID:30885 java.lang.OutOfMemoryError:无法在dalvik.system.VMRuntime.newNonMovableArray中分配带有14018312个空闲字节和13MB的26211852字节分配android.graphics上的android.graphics.Bitmap.createBitmap(Bitmap.java:939)的android.graphics.Bitmap.nativeCreate(Native Method)处于android.graphics的android.graphics.Bitmap.createBitmap(Bitmap.java:912)位于id.TestingApp的id.testingapp.android.TestingApp.WelcomeActivity.prepareBackgroundAnimation(WelcomeActivity.java:140)的android.graphics.Bitmap.createScaledBitmap(Bitmap.java:719)上的.bitmap.createBitmap(Bitmap.java:843). android.TestingApp.WelcomeActivity.onCreate(WelcomeActivity.java:72)在android.app.AseCreate(Activity.java:6283)的android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)android.app.ActivityThread上的android.app.Activity.performCreate(Activity.java:6283) .performLaunchActivity(ActivityThread.java:2646)在android.app.ActivityThread.ha 在Android.app.Handler.dispatchMessage上的android.app.ActivityThread.access $ 900(ActivityThread.java:177)的android.app.ActivityThread $ H.handleMessage(ActivityThread.java:1448)的ndleLaunchActivity(ActivityThread.java:2758) Handler.java:102)在android.app.Looper.loop(Looper.java:145)的android.app.ActivityThread.main(ActivityThread.java:5942)at java.lang.reflect.Method.invoke(Native Method)在java.lang.reflect.Method.invoke(Method.java:372)的com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:1400)com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1195)

编辑:

我试图把所有这些都放进去,onDestroyed()但问题仍然存在

@Override
protected void onDestroy() {
    finish();
    bitmapImage = null;
    scaledBitmap = null;
    super.onDestroy();
    Runtime.getRuntime().gc();
    System.gc();
}

Answer 1

为它添加以下代码

@Override
protected void onDestroy() {
    //android.os.Process.killProcess(android.os.Process.myPid());

    super.onDestroy();
    if(scaledBitmap!=null)
            {
                scaledBitmap.recycle();
                scaledBitmap=null;
            }

     }

Answer 2

在活动中,如果您正在调用finish()方法,则会销毁该方法并将其所有资源排入队列以进行垃圾回收.

因此,此活动使用的所有内存将在下一个GC周期中释放.

要么

你可以尝试这个来清理记忆,

@Override
public void onDestroy() {
    super.onDestroy();
    Runtime.getRuntime().gc();      
}

查看此详细信息.希望有所帮助.