Question

int android.graphics.bitmap.getheight'on a null object reference是怎么回

Answer 1

private Bitmap mergeThumbnailBitmap(Bitmap firstBitmap, Bitmap secondBitmap) {
Bitmap bitmap = Bitmap.createBitmap(firstBitmap.getWidth(), firstBitmap
.getHeight(), firstBitmap.getConfig()); // 创建一个 512的图
Canvas canvas = new Canvas(bitmap);
Paint paint = new Paint();
canvas.drawBitmap(firstBitmap, 0,0, null); //第一张图,在大图的x坐标，用坐标，paint
canvas.drawBitmap(secondBitmap, firstBitmap.getWidth(), 0, null);
return bitmap;
}

Answer 2

空引用，建立引用即可