现在Android对于图片的处理要求越来越高，今天主要实现下面截图的圆形图片功能。
圆形圆角图片的主要实现方法有三种：
1. PorterDuffXfermode
2. BitmapShader
3. OutlineProvider
代码如下：
1. 通过PorterDuffXferMode来实现：
package com.jackie.processing.image.view;import android.content.Context;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.PorterDuff;import android.graphics.PorterDuffXfermode;import android.util.AttributeSet;import android.view.View;import com.jackie.processing.image.R;/*** Created by Jackie on /2/27.* 圆角矩形*/public class RoundRectXfermodeView extends View {private Bitmap mSrcBitmap;private Bitmap mDstBitmap;private Paint mPaint;public RoundRectXfermodeView(Context context) {this(context, null);}public RoundRectXfermodeView(Context context, AttributeSet attrs) {this(context, attrs, 0);}public RoundRectXfermodeView(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);initView();}private void initView() {//关闭硬件加速setLayerType(LAYER_TYPE_SOFTWARE, null);mSrcBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.test1);mDstBitmap = Bitmap.createBitmap(mSrcBitmap.getWidth(), mSrcBitmap.getHeight(), Bitmap.Config.ARGB_8888);Canvas canvas = new Canvas(mDstBitmap);mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);//dst// canvas.drawCircle(300, 200, 150, mPaint);canvas.drawRoundRect(0, 0, mSrcBitmap.getWidth(), mSrcBitmap.getHeight(), 50, 50, mPaint);mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));//srccanvas.drawBitmap(mSrcBitmap, 0, 0, mPaint);mPaint.setXfermode(null);}@Overrideprotected void onDraw(Canvas canvas) {super.onDraw(canvas);canvas.drawBitmap(mDstBitmap, 0, 0, null);}}
2. 通过BitmapShader实现
package com.jackie.processing.image.view;import android.content.Context;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.BitmapShader;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.Shader;import android.util.AttributeSet;import android.view.View;import com.jackie.processing.image.R;/*** Created by Jackie on /2/29.*/public class BitmapShaderView extends View {private Bitmap mBitmap;private Paint mPaint;public BitmapShaderView(Context context) {this(context, null);}public BitmapShaderView(Context context, AttributeSet attrs) {this(context, attrs, 0);}public BitmapShaderView(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);}@Overrideprotected void onDraw(Canvas canvas) {super.onDraw(canvas);mBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.test2);BitmapShader shader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);mPaint.setShader(shader);canvas.drawCircle(300, 200, 200, mPaint);}}
3. 通过OutlineProvider来实现
ViewOutlineProvider mViewOutlineProvider = new ViewOutlineProvider() { @Override public void getOutline(View view, Outline outline) { outline.setRoundRect(0, 0, view.getWidth(), view.getHeight(), view.getHeight() / 2); } }; mImageView.setOutlineProvider(mViewOutlineProvider);
效果如下：
