android中图片倒影、圆角效果重绘

本文用来记录一些android 操作图片的方法，方便查看。

1.将Drawable转化为Bitmap 

 1 public static Bitmap drawableToBitmap(Drawable drawable){ 
 2 int width = drawable.getIntrinsicWidth(); 
 3 int height = drawable.getIntrinsicHeight(); 
 4 Bitmap bitmap = Bitmap.createBitmap(width, height, 
 5 drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 
 6 : Bitmap.Config.RGB_565); 
 7 Canvas canvas = new Canvas(bitmap); 
 8 drawable.setBounds(0,0,width,height); 
 9 drawable.draw(canvas); 
10 return bitmap; 
11 }

2.获得圆角图片的方法 

 1 public static Bitmap getRoundedCornerBitmap(Bitmap bitmap,float roundPx){ 
 2 
 3 Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap 
 4 .getHeight(), Config.ARGB_8888); 
 5 Canvas canvas = new Canvas(output); 
 6 
 7 final int color = 0xff424242; 
 8 final Paint paint = new Paint(); 
 9 final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight()); 
10 final RectF rectF = new RectF(rect); 
11 
12 paint.setAntiAlias(true); 
13 canvas.drawARGB(0, 0, 0, 0); 
14 paint.setColor(color); 
15 canvas.drawRoundRect(rectF, roundPx, roundPx, paint); 
16 
17 paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN)); 
18 canvas.drawBitmap(bitmap, rect, rect, paint); 
19 
20 return output; 
21 }

 

3.获得带倒影的图片方法 

public static Bitmap createReflectionImageWithOrigin(Bitmap bitmap){ 
final int reflectionGap = 4; 
int width = bitmap.getWidth(); 
int height = bitmap.getHeight(); 

Matrix matrix = new Matrix(); 
matrix.preScale(1, -1); 

Bitmap reflectionImage = Bitmap.createBitmap(bitmap, 
0, height/2, width, height/2, matrix, false); 

Bitmap bitmapWithReflection = Bitmap.createBitmap(width, (height + height/2), Config.ARGB_8888); 

Canvas canvas = new Canvas(bitmapWithReflection); 
canvas.drawBitmap(bitmap, 0, 0, null); 
Paint deafalutPaint = new Paint(); 
canvas.drawRect(0, height,width,height + reflectionGap, 
deafalutPaint); 

canvas.drawBitmap(reflectionImage, 0, height + reflectionGap, null); 

Paint paint = new Paint(); 
LinearGradient shader = new LinearGradient(0, 
bitmap.getHeight(), 0, bitmapWithReflection.getHeight() 
+ reflectionGap, 0x70ffffff, 0x00ffffff, TileMode.CLAMP); 
paint.setShader(shader); //important
paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN)); 
canvas.drawRect(0, height, width, bitmapWithReflection.getHeight() 
+ reflectionGap, paint); 
return bitmapWithReflection; 
}

转载于:https://www.cnblogs.com/jiedi/archive/2011/12/19/2293905.html