我一直在努力在 Android Print Framework 中预览 PDF 以匹配打印输出。但是，我能够使输出匹配为位图。但是，如果我缩放位图并在位图周围放置空白，打印框架会裁剪掉空白。所以，为了防止这种情况发生，我想在整个 Canvas 的边缘画一个细边框。
这是我必须缩放位图的代码：
public static Bitmap captureScreen(View v) {
Bitmap screenshot = null;
Bitmap output = null;
try {
if (v != null) {
screenshot = Bitmap.createBitmap(v.getMeasuredWidth(), v.getMeasuredHeight(), Bitmap.Config.ARGB_8888);
int width = screenshot.getWidth();
int height = screenshot.getHeight();
int scaledWidth = (int) (width * 0.5);
int scaledHeight = (int) (height * 0.5);
output = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Bitmap scaled = Bitmap.createScaledBitmap(screenshot, scaledWidth, scaledHeight, false);
Canvas canvas = new Canvas(output);
Paint paint = new Paint();
int distX = (width - scaledWidth) / 2;
int distY = (height - scaledHeight) / 2;
canvas.drawBitmap(scaled, distX, distY, paint);
v.draw(canvas);
}
} catch (Exception e) {
Log.d("ScreenShotActivity", "Failed to capture screenshot because:" + e.getMessage());
}
return output;
}
我想在整个画布周围画一个细黑色边框，因为我可以防止打印框架裁剪掉空白。