公司的项目，UI和应用都是我自己做的。前几天设计了一个UI，出现了半边圆角的情况，如下图片所示。图片都来自服务器，肯定不能要求返回的图片按这个格式，必须在应用端对图片进行切角。
Google了好久，发现能找到的代码都是重复的，而且代码垃圾很多。于是按着那段代码的解决方式，自己写了一个实现指定切某一边的工具类。
直接可用的代码：
package com.lurencun.androidsysteminfomation;import android.graphics.Bitmap;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.PorterDuffXfermode;import android.graphics.Rect;import android.graphics.RectF;import android.graphics.Bitmap.Config;import android.graphics.PorterDuff.Mode;/** * @author : 桥下一粒砂 * @email : [email protected] * @date : 2012-11-8 * @desc : */public class BitmapFillet { public static final int ALL = 347120; public static final int TOP = 547120; public static final int LEFT = 647120; public static final int RIGHT = 747120; public static final int BOTTOM = 847120; /** * * 指定图片的切边，对图片进行圆角处理 * @param type 具体参见：[email protected] BitmapFillet.ALL} , [email protected] BitmapFillet.TOP} , * [email protected] BitmapFillet.LEFT} , [email protected] BitmapFillet.RIGHT} , [email protected] BitmapFillet.BOTTOM} * @param bitmap 需要被切圆角的图片 * @param roundPx 要切的像素大小 * @return * */ public static Bitmap fillet(int type,Bitmap bitmap,int roundPx) { try { // 其原理就是：先建立一个与图片大小相同的透明的Bitmap画板 // 然后在画板上画出一个想要的形状的区域。 // 最后把源图片帖上。 final int width = bitmap.getWidth(); final int height = bitmap.getHeight(); Bitmap paintingBoard = Bitmap.createBitmap(width,height, Config.ARGB_8888); Canvas canvas = new Canvas(paintingBoard); canvas.drawARGB(Color.TRANSPARENT, Color.TRANSPARENT, Color.TRANSPARENT, Color.TRANSPARENT); final Paint paint = new Paint(); paint.setAntiAlias(true); paint.setColor(Color.BLACK); if( TOP == type ){ clipTop(canvas,paint,roundPx,width,height); }else if( LEFT == type ){ clipLeft(canvas,paint,roundPx,width,height); }else if( RIGHT == type ){ clipRight(canvas,paint,roundPx,width,height); }else if( BOTTOM == type ){ clipBottom(canvas,paint,roundPx,width,height); }else{ clipAll(canvas,paint,roundPx,width,height); } paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN)); //帖子图 final Rect src = new Rect(0, 0, width, height); final Rect dst = src; canvas.drawBitmap(bitmap, src, dst, paint); return paintingBoard; } catch (Exception exp) { return bitmap; } } private static void clipLeft(final Canvas canvas,final Paint paint,int offset,int width,int height){ final Rect block = new Rect(offset,0,width,height); canvas.drawRect(block, paint); final RectF rectF = new RectF(0, 0, offset * 2 , height); canvas.drawRoundRect(rectF, offset, offset, paint); } private static void clipRight(final Canvas canvas,final Paint paint,int offset,int width,int height){ final Rect block = new Rect(0, 0, width-offset, height); canvas.drawRect(block, paint); final RectF rectF = new RectF(width - offset * 2, 0, width , height); canvas.drawRoundRect(rectF, offset, offset, paint); } private static void clipTop(final Canvas canvas,final Paint paint,int offset,int width,int height){ final Rect block = new Rect(0, offset, width, height); canvas.drawRect(block, paint); final RectF rectF = new RectF(0, 0, width , offset * 2); canvas.drawRoundRect(rectF, offset, offset, paint); } private static void clipBottom(final Canvas canvas,final Paint paint,int offset,int width,int height){ final Rect block = new Rect(0, 0, width, height - offset); canvas.drawRect(block, paint); final RectF rectF = new RectF(0, height - offset * 2 , width , height); canvas.drawRoundRect(rectF, offset, offset, paint); } private static void clipAll(final Canvas canvas,final Paint paint,int offset,int width,int height){ final RectF rectF = new RectF(0, 0, width , height); canvas.drawRoundRect(rectF, offset, offset, paint); }}