實現圖片縮放

private Bitmap resizeImage(Bitmap originalBitmap, int newWidth, int newHeight){
      int width = originalBitmap.getWidth();
      int height = originalBitmap.getHeight();
      //定義欲轉換成的寬、高
//       int newWidth = 200;
//       int newHeight = 200;
      //計算寬、高縮放率
      float scanleWidth = (float)newWidth/width;
      float scanleHeight = (float)newHeight/height;
      //建立操作圖片用的matrix物件 Matrix
      Matrix matrix = new Matrix();
      // 縮放圖片動作
      matrix.postScale(scanleWidth,scanleHeight);   //兩個引數為寬度和高度的縮放
      //旋轉圖片 動作
      //matrix.postRotate(45);
      // 建立新的圖片Bitmap
      Bitmap resizedBitmap = Bitmap.createBitmap(originalBitmap,0,0,width,height,matrix,true);
      return resizedBitmap;
   }