//获取Picture对象
Picture picture = wv_capture.capturePicture();
//得到图片的宽和高（没有reflect图片内容）
int width = picture.getWidth();
int height = picture.getHeight();
if (width > 0 && height > 0) {
  //创建位图
  Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
  Canvas canvas = new Canvas(bitmap);
  //绘制(会调用native方法，完成图形绘制)
  picture.draw(canvas);

}

//获取webview缩放率
float scale = wv_capture.getScale();
//得到缩放后webview内容的高度
int webViewHeight = (int) (wv_capture.getContentHeight()*scale);
Bitmap bitmap = Bitmap.createBitmap(wv_capture.getWidth(),webViewHeight, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
//绘制
wv_capture.draw(canvas);

webView.setDrawingCacheEnabled(true);
...
Bitmap bitmap = webView.getDrawingCache();

View view = context.getWindow().getDecorView();
Bitmap bitmap = Bitmap.createBitmap(view.getWidth(), view.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
view.draw(canvas);
保存到文件

try {
  String fileName = Environment.getExternalStorageDirectory().getPath()+"/webview_capture4.jpg";
  FileOutputStream fos = new FileOutputStream(fileName);
  //压缩bitmap到输出流中
  bitmap.compress(Bitmap.CompressFormat.JPEG, 70, fos);
  fos.close();
  Toast.makeText(WebviewFromGetDecorView.this, "截屏成功", Toast.LENGTH_LONG).show();
  } catch (Exception e) {
    Log.e(TAG, e.getMessage());
  }finally {
    if(bitmap!=null) {
      bitmap.recycle();
    }

  }