实现图片缩放

private Bitmap resizeImage(Bitmap originalBitmap, int newWidth, int newHeight){
int width = originalBitmap.getWidth();
int height = originalBitmap.getHeight();
//定义欲转换成的宽、高
//       int newWidth = 200;
//       int newHeight = 200;
//计算宽、高缩放率
float scanleWidth = (float)newWidth/width;
float scanleHeight = (float)newHeight/height;
//创建操作图片用的matrix对象 Matrix
Matrix matrix = new Matrix();
// 缩放图片动作
matrix.postScale(scanleWidth,scanleHeight);   //两个参数为宽度和高度的缩放
//旋转图片 动作
//matrix.postRotate(45);
// 创建新的图片Bitmap
Bitmap resizedBitmap = Bitmap.createBitmap(originalBitmap,0,0,width,height,matrix,true);
return resizedBitmap;
}