Android圆角图片-蒲公英云

自定义ImageView

package com.interjoy.testdemo.views;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.ImageView;
import java.text.SimpleDateFormat;
import java.util.Date;
/** * 主要有两种方式实现，Xfermode方式和bitmapShader方式 * Xfermode * * @author ylwang */
public class RoundCornerImageView extends ImageView { 
    private Paint mPaint;
    private Paint mPaint2;
    private int roundHeight = 300;
    private int roundWidth = 300;
    private SimpleDateFormat simpleDateFormat;
    public RoundCornerImageView(Context context, AttributeSet attrs,
                                int defStyle) {
        super(context, attrs, defStyle);
    }
    public RoundCornerImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }
    public RoundCornerImageView(Context context) {
        super(context);
        init();
    }
    private void init() {
        mPaint = new Paint();
        mPaint.setColor(Color.WHITE);
        mPaint.setAntiAlias(true);
        //16种状态
        mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
        mPaint2 = new Paint();
        mPaint2.setXfermode(null);
        simpleDateFormat = new SimpleDateFormat("'[秒:毫秒] 'ss:SSS");
    }
    int i = 0;
    @Override
    public void onDraw(Canvas canvas) {
        String time = simpleDateFormat.format(new Date());
        int width = getWidth();
        Log.d("&&&&", "onDraw 执行次数 = " + (++i) + ", width = " + width + ", 执行时刻->" + time);
        if (width == 0) {
            super.onDraw(canvas);
            return;
        }
        Bitmap bitmap = Bitmap.createBitmap(getWidth(), getHeight(), Config.ARGB_8888);
        Canvas canvas2 = new Canvas(bitmap);
        super.onDraw(canvas2);
        drawLeftUp(canvas2);
        drawRightUp(canvas2);
        drawLeftDown(canvas2);
        drawRightDown(canvas2);
        canvas.drawBitmap(bitmap, 0, 0, mPaint2);
        bitmap.recycle();
    }
    private void drawLeftUp(Canvas canvas) {
        Path path = new Path();
        path.moveTo(0, roundHeight);
        path.lineTo(0, 0);
        path.lineTo(roundWidth, 0);
        //arcTo的第二个参数是以多少度为开始点，第三个参数-90度表示逆时针画弧，正数表示顺时针
        path.arcTo(new RectF(0, 0, roundWidth * 2, roundHeight * 2), -90, -90);
        path.close();
        canvas.drawPath(path, mPaint);
    }
    private void drawLeftDown(Canvas canvas) {
        Path path = new Path();
        path.moveTo(0, getHeight() - roundHeight);
        path.lineTo(0, getHeight());
        path.lineTo(roundWidth, getHeight());
        path.arcTo(new RectF(0, getHeight() - roundHeight * 2, 0 + roundWidth * 2, getHeight()), 90, 90);
        path.close();
        canvas.drawPath(path, mPaint);
    }
    private void drawRightDown(Canvas canvas) {
        Path path = new Path();
        path.moveTo(getWidth() - roundWidth, getHeight());
        path.lineTo(getWidth(), getHeight());
        path.lineTo(getWidth(), getHeight() - roundHeight);
        path.arcTo(new RectF(getWidth() - roundWidth * 2, getHeight() - roundHeight * 2, getWidth(), getHeight()), 0, 90);
        path.close();
        canvas.drawPath(path, mPaint);
    }
    private void drawRightUp(Canvas canvas) {
        Path path = new Path();
        path.moveTo(getWidth(), roundHeight);
        path.lineTo(getWidth(), 0);
        path.lineTo(getWidth() - roundWidth, 0);
        path.arcTo(new RectF(getWidth() - roundWidth * 2, 0, getWidth(), 0 + roundHeight * 2), -90, 90);
        path.close();
        canvas.drawPath(path, mPaint);
    }
}

布局文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context="com.interjoy.testdemo.Activities.ClipActivity">
    <com.interjoy.testdemo.views.RoundCornerImageView android:layout_margin="20dp" android:src="@drawable/yy6" android:id="@+id/iv_clip" android:layout_width="200dp" android:layout_height="200dp" />
    <Button android:id="@+id/btn_show_image" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="显示另外一张图片" />
</LinearLayout>

Activity调用

package com.interjoy.testdemo.Activities;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import com.interjoy.testdemo.R;
import com.interjoy.testdemo.views.RoundCornerImageView;
public class ClipActivity extends Activity { 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_clip);
        initViews();
    }
    private void initViews() {
        final ImageView imageView = new RoundCornerImageView(this);
        addContentView(imageView,new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,ViewGroup.LayoutParams.WRAP_CONTENT));
        findViewById(R.id.btn_show_image).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                imageView.setImageResource(R.drawable.yy6);
            }
        });
    }
}