因为View不可见,所以直接调用转换 bitmap 的方法不可行,必须得先把View 绘制出来再去转换。
项目中使用的是ScrollView,所以绘制的方法如下:
val scrollView = view.findViewById<ScrollView>(R.id.scrollView)
scrollView.measure(
View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED)
)
scrollView.layout(0,0,scrollView.measuredWidth,scrollView.measuredHeight)
然后再调用 ScrollView 的截图方法即可:
public static Bitmap snapshotByScrollView(final ScrollView scrollView, final Bitmap.Config config) {
if (scrollView == null || config == null) return null;
try {
View view = scrollView.getChildAt(0);
int width = view.getWidth();
int height = view.getHeight();
Bitmap bitmap = Bitmap.createBitmap(width, height, config);
Canvas canvas = new Canvas(bitmap);
canvas.drawColor(BACKGROUND_COLOR);
scrollView.layout(0, 0, scrollView.getMeasuredWidth(),
scrollView.getMeasuredHeight());
scrollView.draw(canvas);
return bitmap;
} catch (Exception e) {
Log.i(TAG, "snapshotByScrollView exception:${e}");
}
return null;
}