我使用以下代码捕获设备的屏幕(Android 5.1.1)。但是,当在我的朋友的智能手机(Android 7.1.1)上测试相同的代码时,所有图像均为黑色。
有一些修改能够解决它?
还是没有解决方案的情况?
这是代码:
====================================================================================
屏幕截图:
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
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.Image.Plane;
import android.media.ImageReader;
import android.media.ImageReader.OnImageAvailableListener;
import android.media.projection.MediaProjection;
import android.media.projection.MediaProjection.Callback;
import android.media.projection.MediaProjectionManager;
import android.os.AsyncTask;
import android.support.annotation.NonNull;
import android.support.annotation.UiThread;
import android.util.Log;
import android.view.WindowManager;
import android.widget.Toast;
import java.io.FileOutputStream;
import static android.os.Environment.getExternalStorageDirectory;
public class ScreenShotManager {
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;
public static final ScreenShotManager INSTANCE = new ScreenShotManager();
private Intent mIntent;
private ScreenShotManager() {
}
public void requestScreenshotPermission(@NonNull Activity activity, int requestId) {
MediaProjectionManager mediaProjectionManager = (MediaProjectionManager) activity.getSystemService(Context.MEDIA_PROJECTION_SERVICE);
activity.startActivityForResult(mediaProjectionManager.createScreenCaptureIntent(), requestId);
}
public void onActivityResult(int resultCode, Intent data) {
if (resultCode == Activity.RESULT_OK && data != null)
mIntent = data;
else mIntent = null;
}
@UiThread
public boolean takeScreenshot(@NonNull Context context) {
if (mIntent == null)
return false;
final MediaProjectionManager mediaProjectionManager = (MediaProjectionManager) context.getSystemService(Context.MEDIA_PROJECTION_SERVICE);
final MediaProjection mediaProjection = mediaProjectionManager.getMediaProjection(Activity.RESULT_OK, mIntent);
if (mediaProjection == null)
return false;
final int density = context.getResources().getDisplayMetrics().densityDpi;
final Point windowSize = new Point();
WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
windowManager.getDefaultDisplay().getRealSize(windowSize);
final int width = windowSize.x, height = windowSize.y;
final Context applicationContext = context.getApplicationContext();
// start capture reader
final ImageReader imageReader = ImageReader.newInstance(width, height, PixelFormat.RGBA_8888, 1);
final VirtualDisplay virtualDisplay = mediaProjection.createVirtualDisplay(SCREENCAP_NAME, width, height, density, VIRTUAL_DISPLAY_FLAGS, imageReader.getSurface(), null, null);
imageReader.setOnImageAvailableListener(new OnImageAvailableListener() {
@Override
public void onImageAvailable(final ImageReader reader) {
Log.d("AppLog", "onImageAvailable");
mediaProjection.stop();
new AsyncTask<Void, Void, Bitmap>() {
@Override
protected Bitmap doInBackground(final Void... params) {
Image image = null;
Bitmap bitmap = null;
try {
image = reader.acquireLatestImage();
if (image != null) {
Plane[] planes = image.getPlanes();
ByteBuffer buffer = planes[0].getBuffer();
int pixelStride = planes[0].getPixelStride(), rowStride = planes[0].getRowStride(), rowPadding = rowStride - pixelStride * width;
bitmap = Bitmap.createBitmap(width + rowPadding / pixelStride, height, Config.ARGB_8888);
bitmap.copyPixelsFromBuffer(buffer);
FileOutputStream out = null;
out = new FileOutputStream(getExternalStorageDirectory() + File.separator + "test.jpeg");
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, out);
// fix the extra width from Image
Bitmap croppedBitmap;
croppedBitmap = Bitmap.createBitmap(bitmap, 0, 0, windowSize.x, windowSize.y);
if (croppedBitmap != bitmap)
bitmap.recycle();
return croppedBitmap;
}
} catch (Exception e) {
if (bitmap != null)
bitmap.recycle();
e.printStackTrace();
}
if (image != null)
image.close();
reader.close();
return null;
}
@Override
protected void onPostExecute(final Bitmap bitmap) {
super.onPostExecute(bitmap);
Log.d("AppLog", "Got bitmap?" + (bitmap != null));
Toast.makeText(applicationContext, "Got bitmap?" + (bitmap != null), Toast.LENGTH_SHORT).show();
}
}.execute();
}
}, null);
mediaProjection.registerCallback(new Callback() {
@Override
public void onStop() {
super.onStop();
if (virtualDisplay != null)
virtualDisplay.release();
imageReader.setOnImageAvailableListener(null, null);
mediaProjection.unregisterCallback(this);
}
}, null);
return true;
}
}
MAIN
class PermissionUtils {
public static final int REQUEST_EXTERNAL_STORAGE = 2000;
public static void requestExternal(Activity context) {
if (!checkExternal(context)) {
ActivityCompat.requestPermissions(context, new String[]{
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.WRITE_EXTERNAL_STORAGE},
REQUEST_EXTERNAL_STORAGE);
}
}
public static boolean checkExternal(Context context) {
return !(ActivityCompat.checkSelfPermission(context, Manifest.permission.READ_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED
&& ActivityCompat.checkSelfPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED);
}
}
private final int REQUEST_CODE_CAPTURE_PERM = 1234;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
PermissionUtils.requestExternal(this);
ScreenShotManager.INSTANCE.requestScreenshotPermission(MainActivity.this, REQUEST_CODE_CAPTURE_PERM);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_CODE_CAPTURE_PERM) {
ScreenShotManager.INSTANCE.onActivityResult(resultCode, data);
ScreenShotManager.INSTANCE.takeScreenshot(MainActivity.this);
}
}
我已经阅读了您的问题,一切对我来说似乎都是正确的。在版本之间迁移时,您唯一需要注意的是,每个版本的代码可能有所不同,因此您可能需要查看版本5.1.1使用的代码是否与代码版本相同7.1.1使用。如果这不起作用,请回复,我将找到另一种解决方案并告诉您。祝你好运!