圆角效果：
?
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
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;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.widget.ImageView;
public class Main extends Activity {
??? /** Called when the activity is first created. */
??? @Override
??? public void onCreate(Bundle savedInstanceState) {
??????? super.onCreate(savedInstanceState);
?????
??????? setContentView(R.layout.main);??
??????? Drawable drawable = getResources().getDrawable(R.drawable.jpg1);
??????? BitmapDrawable bitmapDrawable = (BitmapDrawable)drawable;
??????? Bitmap bitmap = bitmapDrawable.getBitmap();???
??????
???????? ImageView imageView = (ImageView)findViewById(R.id.imgShow);
???????? imageView.setImageBitmap(Main.getRoundedCornerBitmap(bitmap));???????
???????
??? }
?// 将图片的四角圆化
??? public static Bitmap getRoundedCornerBitmap(Bitmap bitmap) {
??? ?
??????? Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),?
??????????? bitmap.getHeight(), Config.ARGB_8888);
??????? //得到画布
??????? Canvas canvas = new Canvas(output);
????
???????
?????? //将画布的四角圆化
??????? final int color = Color.RED;?
??????? final Paint paint = new Paint();?
??????? //得到与图像相同大小的区域? 由构造的四个值决定区域的位置以及大小
??????? final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());?
??????? final RectF rectF = new RectF(rect);?
??????? //值越大角度越明显
??????? final float roundPx = 50;?
??????
??????? paint.setAntiAlias(true);?
??????? canvas.drawARGB(0, 0, 0, 0);?
??????? paint.setColor(color);?
??????? //drawRoundRect的第2,3个参数一样则画的是正圆的一角，如果数值不同则是椭圆的一角
??????? canvas.drawRoundRect(rectF, roundPx,roundPx, paint);?
??????
??????? paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));?
??????? canvas.drawBitmap(bitmap, rect, rect, paint);?
??????
??????? return output;?
????? }
???
}
很实用