Android截图和保存图片到指定目录

public static Bitmap getScreenShot() {
    try {
        //反射 SurfaceControl screenshot()被隐藏
        String surfaceClassName = "android.view.SurfaceControl";
        @SuppressLint("PrivateApi")
        Class<?> clazz = Class.forName(surfaceClassName);
        @SuppressLint("DiscouragedPrivateApi")
        Method screenshot = clazz.getDeclaredMethod("screenshot", Rect.class, int.class, int.class, int.class);
        screenshot.setAccessible(true);
        return (Bitmap) (screenshot.invoke(clazz, new Rect(0, 0, CaptureUtils.getScreenWidth(), CaptureUtils.getScreenHeight()),
                CaptureUtils.getScreenWidth(), CaptureUtils.getScreenHeight(), 0));
    } catch (Exception e) {
        e.printStackTrace();
    }
    return null;
}

DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getRealMetrics(dm);

private static final String mDiskPath = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator + "BiuCapture";

public static String saveBitmap(Bitmap bitmap) {
    String path = mDiskPath + File.separator + SystemClock.uptimeMillis() + ".png";
    Log.d(CaptureApp.TAG, "saveBitmap path : " + path);
    FileOutputStream fileOutputStream = null;
    try {
        File file = new File(mDiskPath);
        if (!file.exists()) {
            file.mkdirs();
        }
        file = new File(path);
        if (!file.exists()) {
            Log.d(CaptureApp.TAG, "saveBitmap createNewFile : " + file.createNewFile());
        }
        fileOutputStream = new FileOutputStream(file);
        bitmap.compress(Bitmap.CompressFormat.PNG, 100, fileOutputStream);
        fileOutputStream.flush();
        return path;
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        if (null != fileOutputStream) {
            try {
                fileOutputStream.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
    return null;
}