Android 中的黑色屏幕截图 [英] Screenshot Black in Android

问题描述

我一直在研究如何在 android 中以编程方式截取屏幕截图，但是当它截取屏幕截图时，我得到了一个工具栏和黑屏，而不是屏幕上实际显示的内容.

I've been working out how to take a screenshot programmatically in android, however when it screenshots I get a toolbar and black screen captured instead of what is actually on the screen.

我还尝试在我为谷歌地图创建的自定义 InfoWindow 布局中对特定的 TextView 进行屏幕截图.但这会在下面的第二行创建一个空指针异常.

I've also tried to screenshot a particular TextView within the custom InfoWindow layout I created for the google map. But that creates a null pointer exception on the second line below.

TextView v1 = (TextView)findViewById(R.id.tv_code);
v1.setDrawingCacheEnabled(true);

无论如何，是否可以在不安装android屏幕截图库的情况下实际截取屏幕上的内容，或者在自定义InfoWindow布局中截取TextView

Is there anyway to either actually screenshot what is on the screen without installing android screenshot library or to screenshot a TextView within a custom InfoWindow layout

这是我的截图方法:

/**
 * Method to take a screenshot programmatically
 */
private void takeScreenshot(){
    try {
        //TextView I could screenshot instead of the whole screen:
        //TextView v1 = (TextView)findViewById(R.id.tv_code);

        View v1 = getWindow().getDecorView().getRootView();
        v1.setDrawingCacheEnabled(true);
        Bitmap bitmap = Bitmap.createBitmap(v1.getDrawingCache());
        v1.setDrawingCacheEnabled(false);


        ByteArrayOutputStream bytes = new ByteArrayOutputStream();
        bitmap.compress(Bitmap.CompressFormat.JPEG, 40, bytes);
        File f = new File(Environment.getExternalStorageDirectory()
                + File.separator + "test.jpg");

        FileOutputStream fo = new FileOutputStream(f);
        fo.write(bytes.toByteArray());
        fo.flush();
        fo.close();

        MediaStore.Images.Media.insertImage(getContentResolver(), f.getAbsolutePath(), f.getName(), f.getName());
        Log.d("debug", "Screenshot saved to gallery");

        Toast.makeText(HuntActivity.this,"Code Saved!",Toast.LENGTH_LONG).show();

    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

我已将方法更改为来源提供的方法

I have changed the method to the one provided from the source

如何以编程方式拍摄/合并 Google 地图 v2 和 xml 布局的屏幕截图?

但是它没有截图任何东西.

However it does not screenshot anything.

public void captureMapScreen() {
    GoogleMap.SnapshotReadyCallback callback = new GoogleMap.SnapshotReadyCallback() {

        @Override
        public void onSnapshotReady(Bitmap snapshot) {
            try {
                View mView = getWindow().getDecorView().getRootView();
                mView.setDrawingCacheEnabled(true);
                Bitmap backBitmap = mView.getDrawingCache();
                Bitmap bmOverlay = Bitmap.createBitmap(
                        backBitmap.getWidth(), backBitmap.getHeight(),
                        backBitmap.getConfig());

                Canvas canvas = new Canvas(bmOverlay);
                canvas.drawBitmap(backBitmap, 0, 0, null);
                canvas.drawBitmap(snapshot, new Matrix(), null);

                FileOutputStream out = new FileOutputStream(
                        Environment.getExternalStorageDirectory()
                                + "/"
                                + System.currentTimeMillis() + ".jpg");

                bmOverlay.compress(Bitmap.CompressFormat.JPEG, 90, out);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    };
    mMap.snapshot(callback);
}

推荐答案

我已经想通了！

/**
 * Method to take a screenshot programmatically
 */
private void takeScreenshot(){
    GoogleMap.SnapshotReadyCallback callback = new GoogleMap.SnapshotReadyCallback() {
        @Override
        public void onSnapshotReady(Bitmap bitmap) {
            Bitmap b = bitmap;
            String timeStamp = new SimpleDateFormat(
                    "yyyyMMdd_HHmmss", Locale.getDefault())
                    .format(new java.util.Date());

            String filepath = timeStamp + ".jpg";

            try{
                OutputStream fout = null;
                fout = openFileOutput(filepath,MODE_WORLD_READABLE);
                bitmap.compress(Bitmap.CompressFormat.JPEG, 90, fout);
                fout.flush();
                fout.close();
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
            saveImage(filepath);
        }
    };
    mMap.snapshot(callback);
}

/**
 * Method to save the screenshot image
 * @param filePath  the file path
 */
public void saveImage(String filePath)
{
    File file = this.getFileStreamPath(filePath);

    if(!filePath.equals(""))
    {
        final ContentValues values = new ContentValues(2);
        values.put(MediaStore.Images.Media.MIME_TYPE, "image/jpeg");
        values.put(MediaStore.Images.Media.DATA, file.getAbsolutePath());
        final Uri contentUriFile = getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
        Toast.makeText(HuntActivity.this,"Code Saved to files!",Toast.LENGTH_LONG).show();
    }
    else
    {
        System.out.println("ERROR");
    }
}

我已经修改了此链接中的代码，因此它不会共享，而只是保存图像.

I have adapted the code from this link so it doesn't share and instead just saves the image.

截取 GoogleMap Android API V2 的屏幕截图

感谢大家的帮助

这篇关于Android 中的黑色屏幕截图的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！