android指定角のフィレットピクチャ処理

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 :
 * @email  
 * @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;
    
    /**
     * 
     *        ，         
     * @param type     ：{@link BitmapFillet.ALL} , {@link BitmapFillet.TOP} , 
     * 				{@link BitmapFillet.LEFT} , {@link BitmapFillet.RIGHT} , {@link BitmapFillet.BOTTOM}
     * @param bitmap          
     * @param roundPx        
     * @return
     *
     */
    public static Bitmap fillet(int type,Bitmap bitmap,int roundPx) {
        try {
        	//      ：                Bitmap  
        	//                   。
        	//         。
        	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)); 
            //   
            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);
    }
}