1、圖片縮放

按照原圖片寬高比縮放圖片寬高即可。

• 方法1：重新設定view寬高屬性

//原圖：width/height = 3/2
var newWidth = 300
var dw = newWidth
var dh = newWidth*2/3
zoomRotateImage.layoutParams = LinearLayout.LayoutParams(dw,dh)

• 方法2：重新渲染點陣圖

// 獲得圖片的寬高
var width = bm.getWidth()
var height = bm.getHeight()
// 計算縮放比例
var scaleWidth = (newWidth as
 
 Float) / width
var scaleHeight = (newHeight as Float) / height
// 取得想要縮放的matrix引數
var matrix =Matrix()
matrix.postScale(scaleWidth, scaleHeight)
// 得到新的圖片
Bitmap newbm = Bitmap.createBitmap(bm, 0, 0, width, height, matrix, true)
zoomRotateImage.setImageBitmap(newbm)

2、圖片旋轉

• 方法1：重新渲染點陣圖

var bitmap = (resources.getDrawable
 
(R.drawable.ic_launcher) as BitmapDrawable).getBitmap() 
var matrix  = Matrix()
matrix.setRotate(90)
var new = Bitmap.create(bitmap,0,bitmap.getWidth(),0,bitmap.getHeight(),matrix)  
imageView.setBitmapResource(bitmap) 

• 方法2：設定ImageView旋轉屬性

可在xml中設定：

android:rotation="90"  

也可以在activity程式碼中寫

image.setPivotX
 
(image.getWidth()/2)  
image.setPivotY(image.getHeight()/2)  
image.setRotation(90)

//或者

var progress = 90 as Float
var matrix=Matrix()  
rotateImage.setScaleType(ScaleType.MATRIX)
matrix.postRotate(progress, pivotX, pivotY)  
rotateImage.setImageMatrix(matrix)

• 方法3：使用旋轉動畫

//rotateImage.animate().rotation(90)

var rotateAnimation = RotateAnimation(lastAngle, progress, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 1)  
rotateAnimation.setFillAfter(true)
rotateAnimation.setDuration(50)
rotateAnimation.setRepeatCount(0)  
rotateImage.startAnimation(rotateAnimation)

參考資料：