"RuntimeException: Canvas: trying to use a recycled bitmap android.graphics.Bitmap"尝试将位图从活动传递到服务

Question

我正在Android Studio中编写一个小型Android程序，该程序使用MediaProjecting抓取整个屏幕的屏幕截图，然后我想将该屏幕截图作为位图传递到我的系统覆盖层(基于聊天头示例(。当 MediaProjection 运行并且 Imagereader 创建位图时，我将位图传递到类全局变量中，以便可以将其传递到我的系统覆盖服务中并显示它。我遇到了一个问题，当服务中的图像视图尝试读取 bmp 时，出现如下错误：

java.lang.RuntimeException: Canvas: trying to use a recycled bitmap android.graphics.Bitmap@347a4d5

据我了解，垃圾回收器会迅速吃掉传递的位图，当系统覆盖层试图抓取它时，数据就消失了。有人可以指出我如何保留位图的正确方向吗？

主要活动

package com.example.chatheads;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.graphics.PixelFormat;
import android.graphics.Point;
import android.media.ImageReader;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.PixelFormat;
import android.graphics.Point;
import android.hardware.display.DisplayManager;
import android.hardware.display.VirtualDisplay;
import android.media.Image;
import android.media.ImageReader;
import android.media.projection.MediaProjection;
import android.media.projection.MediaProjectionManager;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.util.DisplayMetrics;
import android.util.Log;
import android.view.Display;
import android.view.OrientationEventListener;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
public class MainActivity extends Activity {
Button startService,stopService;

private static final String TAG = MainActivity.class.getName();
private static final int REQUEST_CODE = 100;
private static String STORE_DIRECTORY;
private static int IMAGES_PRODUCED;
private static final String SCREENCAP_NAME = "screencap";
private static final int VIRTUAL_DISPLAY_FLAGS = DisplayManager.VIRTUAL_DISPLAY_FLAG_OWN_CONTENT_ONLY | DisplayManager.VIRTUAL_DISPLAY_FLAG_PUBLIC;
private static MediaProjection sMediaProjection;
private MediaProjectionManager mProjectionManager;
private ImageReader mImageReader;
private Handler mHandler;
private Display mDisplay;
private VirtualDisplay mVirtualDisplay;
private int mDensity;
private int mWidth;
private int mHeight;
private int mRotation;
private OrientationChangeCallback mOrientationChangeCallback;
private Image image = null;
private Bitmap bitmap = null;
Globals sharedData = Globals.getInstance();
public Bitmap getObjectContainer() {
return bitmap;
}
private class ImageAvailableListener implements ImageReader.OnImageAvailableListener {
@Override
public void onImageAvailable(ImageReader reader) {
FileOutputStream fos = null;

try {
image = mImageReader.acquireLatestImage();
if (image != null) {
Image.Plane[] planes = image.getPlanes();
ByteBuffer buffer = planes[0].getBuffer();
int pixelStride = planes[0].getPixelStride();
int rowStride = planes[0].getRowStride();
int rowPadding = rowStride - pixelStride * mWidth;
// create bitmap
bitmap = Bitmap.createBitmap(mWidth + rowPadding / pixelStride, mHeight, Bitmap.Config.ARGB_8888);
bitmap.copyPixelsFromBuffer(buffer);
sharedData.setScreenshot(bitmap);
// write bitmap to a file
// fos = new FileOutputStream(STORE_DIRECTORY + "/myscreen_" + IMAGES_PRODUCED + ".png");
//bitmap.compress(CompressFormat.JPEG, 100, fos);
IMAGES_PRODUCED++;
//Log.e(TAG, "captured image: " + IMAGES_PRODUCED);
String s = ("captured image: " + String.valueOf(IMAGES_PRODUCED));
Toast toast1 = Toast.makeText(getBaseContext(),s, Toast.LENGTH_SHORT);
toast1.show();
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (fos!=null) {
try {
fos.close();
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
if (bitmap!=null) {
bitmap.recycle();
}
if (image!=null) {
image.close();
}
}
}
}
private class OrientationChangeCallback extends OrientationEventListener {
public OrientationChangeCallback(Context context) {
super(context);
}
@Override
public void onOrientationChanged(int orientation) {
synchronized (this) {
final int rotation = mDisplay.getRotation();
if (rotation != mRotation) {
mRotation = rotation;
try {
// clean up
if(mVirtualDisplay != null) mVirtualDisplay.release();
if(mImageReader != null) mImageReader.setOnImageAvailableListener(null, null);
// re-create virtual display depending on device width / height
createVirtualDisplay();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
}
private class MediaProjectionStopCallback extends MediaProjection.Callback {
@Override
public void onStop() {
Log.e("ScreenCapture", "stopping projection.");
mHandler.post(new Runnable() {
@Override
public void run() {
if(mVirtualDisplay != null) mVirtualDisplay.release();
if(mImageReader != null) mImageReader.setOnImageAvailableListener(null, null);
if(mOrientationChangeCallback != null) mOrientationChangeCallback.disable();
sMediaProjection.unregisterCallback(MediaProjectionStopCallback.this);
}
});
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sharedData.setValue(1);
// call for the projection manager
mProjectionManager = (MediaProjectionManager) getSystemService(Context.MEDIA_PROJECTION_SERVICE);
// start projection
Button startButton = (Button)findViewById(R.id.startButton);
startButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
startProjection();
}
});
// stop projection
Button stopButton = (Button)findViewById(R.id.stopButton);
stopButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
stopProjection();
}
});
// start capture handling thread
new Thread() {
@Override
public void run() {
Looper.prepare();
mHandler = new Handler();
Looper.loop();
}
}.start();

startService=(Button)findViewById(R.id.startService);
stopService=(Button)findViewById(R.id.stopService);
startService.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
startService(new Intent(getApplication(), ChatHeadService.class));
}
});
stopService.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
stopService(new Intent(getApplication(), ChatHeadService.class));
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_CODE) {
sMediaProjection = mProjectionManager.getMediaProjection(resultCode, data);
if (sMediaProjection != null) {
File externalFilesDir = getExternalFilesDir(null);
if (externalFilesDir != null) {
STORE_DIRECTORY = externalFilesDir.getAbsolutePath() + "/screenshots/";
File storeDirectory = new File(STORE_DIRECTORY);
if (!storeDirectory.exists()) {
boolean success = storeDirectory.mkdirs();
if (!success) {
Log.e(TAG, "failed to create file storage directory.");
return;
}
}
} else {
Log.e(TAG, "failed to create file storage directory, getExternalFilesDir is null.");
return;
}
// display metrics
DisplayMetrics metrics = getResources().getDisplayMetrics();
mDensity = metrics.densityDpi;
mDisplay = getWindowManager().getDefaultDisplay();
// create virtual display depending on device width / height
createVirtualDisplay();
// register orientation change callback
mOrientationChangeCallback = new OrientationChangeCallback(this);
if (mOrientationChangeCallback.canDetectOrientation()) {
mOrientationChangeCallback.enable();
}
// register media projection stop callback
sMediaProjection.registerCallback(new MediaProjectionStopCallback(), mHandler);
}
}
}
/****************************************** UI Widget Callbacks *******************************/
private void startProjection() {
startActivityForResult(mProjectionManager.createScreenCaptureIntent(), REQUEST_CODE);
}
private void stopProjection() {
mHandler.post(new Runnable() {
@Override
public void run() {
if (sMediaProjection != null) {
sMediaProjection.stop();
}
}
});
}
/****************************************** Factoring Virtual Display creation ****************/
private void createVirtualDisplay() {
// get width and height
Point size = new Point();
mDisplay.getSize(size);
mWidth = size.x;
mHeight = size.y;
// start capture reader
mImageReader = ImageReader.newInstance(mWidth, mHeight, PixelFormat.RGBA_8888, 2);
mVirtualDisplay = sMediaProjection.createVirtualDisplay(SCREENCAP_NAME, mWidth, mHeight, mDensity, VIRTUAL_DISPLAY_FLAGS, mImageReader.getSurface(), null, mHandler);
mImageReader.setOnImageAvailableListener(new ImageAvailableListener(), mHandler);
}
}

服务

package com.example.chatheads;    
import android.app.Service;
import android.content.Intent;
import android.graphics.PixelFormat;
import android.graphics.Rect;
import android.os.IBinder;
import android.util.DisplayMetrics;
import android.view.Display;
import android.view.Gravity;
import android.view.MotionEvent;
import android.view.View;
import android.view.WindowManager;
import android.widget.ImageView;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.view.View;
import android.widget.Toast;

public class ChatHeadService extends Service {
private WindowManager windowManager;
private ImageView chatHead;
WindowManager.LayoutParams params;
Globals sharedData = Globals.getInstance();

@Override
public void onCreate() {
super.onCreate();
windowManager = (WindowManager) getSystemService(WINDOW_SERVICE);
DisplayMetrics displayMetrics = new DisplayMetrics();
windowManager.getDefaultDisplay().getMetrics(displayMetrics);
int h = displayMetrics.heightPixels, w = displayMetrics.widthPixels;
Bitmap.Config conf = Bitmap.Config.ARGB_8888; // see other conf types
final Bitmap bmp = Bitmap.createBitmap(w, h, conf); // this creates a MUTABLE bitmap
Canvas canvas = new Canvas(bmp);
Paint paint = new Paint();
paint.setColor(Color.BLACK);
paint.setStrokeWidth(5);
paint.setAlpha(60);
Rect rect=new Rect(0, 0, bmp.getWidth(), bmp.getHeight());
canvas.drawRect(rect,paint);
paint.setColor(Color.GREEN);
canvas.drawLine(0, 0, 0, h, paint);
canvas.drawLine(0, 0, w, 0, paint);
canvas.drawLine(w, 0, h, w, paint);
canvas.drawLine(0, 0, 0, w, paint);

chatHead = new ImageView(this);
chatHead.setImageResource(R.drawable.face1);
params= new WindowManager.LayoutParams(
WindowManager.LayoutParams.WRAP_CONTENT,
WindowManager.LayoutParams.WRAP_CONTENT,
WindowManager.LayoutParams.TYPE_PHONE,
WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE,
PixelFormat.TRANSLUCENT);
params.gravity = Gravity.TOP | Gravity.LEFT;
params.x = 0;
params.y = 1000;



//this code is for dragging the chat head
chatHead.setOnTouchListener(new View.OnTouchListener() {
private int initialX;
private int initialY;
private float initialTouchX;
private float initialTouchY;
boolean isExpanded = false;
@Override
public boolean onTouch(View v, MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
initialX = params.x;
initialY = params.y;
initialTouchX = event.getRawX();
initialTouchY = event.getRawY();
int n = sharedData.getValue();
//Toast toast1 = Toast.makeText(getBaseContext(),String.valueOf(n), Toast.LENGTH_SHORT);
//toast1.show();
if (isExpanded == true){
chatHead.setImageResource(R.drawable.face1);
isExpanded=false;
params.x = 0;
params.y = 1000;
windowManager.updateViewLayout(chatHead, params);
}
else{
//chatHead.setImageResource(R.drawable.clear);
Bitmap bmp2 = sharedData.getScreenshot();
chatHead.setImageBitmap(bmp2);
isExpanded = true;
params.x = 0;
params.y = 0;
windowManager.updateViewLayout(chatHead, params);
}
return true;
case MotionEvent.ACTION_UP:
//chatHead.setImageResource(R.drawable.test);
return true;
/*case MotionEvent.ACTION_MOVE:
params.x = initialX
+ (int) (event.getRawX() - initialTouchX);
params.y = initialY
+ (int) (event.getRawY() - initialTouchY);
windowManager.updateViewLayout(chatHead, params);
return true;*/
}
return false;
}
});
windowManager.addView(chatHead, params);
}
@Override
public void onDestroy() {
super.onDestroy();
if (chatHead != null)
windowManager.removeView(chatHead);
}
@Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
}

全局

package com.example.chatheads;
import android.graphics.Bitmap;
public class Globals {
private static Globals instance = new Globals();
// Getter-Setters
public static Globals getInstance() {
return instance;
}
public static void setInstance(Globals instance) {
Globals.instance = instance;
}
private Globals() {
}
private int testi;
private Bitmap bmpscreenshot;
public Bitmap getScreenshot(){
return bmpscreenshot;
}
public void setScreenshot(Bitmap bmp){
this.bmpscreenshot = bmp;
}
public int getValue() {
return testi;
}
public void setValue(int testi) {
this.testi = testi;
}
}

Answer 1

你似乎过早地调用bitmap.recycle((。在服务实际处理数据后调用它。

Answer 2

如果要将位图从活动传递到服务手段，请将位图转换为 ByteArray

Intent i = new Intent(this, YourService.class);
Bitmap b; // your bitmap
ByteArrayOutputStream bs = new ByteArrayOutputStream();
b.compress(Bitmap.CompressFormat.PNG, 50, bs);
i.putExtra("byteArray", bs.toByteArray());
startService(i);

在服务中重写启动命令

public int onStartCommand (Intent intent, int flags, int startId) {
Bitmap b = BitmapFactory.decodeByteArray(
getIntent().getByteArrayExtra("byteArray"),0,getIntent()
.getByteArrayExtra("byteArray").length);    
return null;
}