java更改图像的宽度和高度

Question

我想更改图像的高度和宽度。使用canvas显示图像：

canvas.drawBitmap (_image, 0, 0, null);

如何更改位图的大小

Answer 1

或Bitmap.createScaledBitmap(...)

Answer 2

使用矩阵：

int width = bitmap.getWidth();
int height = bitmap.getHeight();

float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;      

matrix = new Matrix();

matrix.postScale(scaleWidth, scaleHeight);

Bitmap resizedBitmap = Bitmap.createBitmap(bitmap, 0, 0,
                    width, height, matrix, true);