自定义圆形图片

自定义View

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.PorterDuff.Mode;
import android.graphics.PorterDuffXfermode;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;

public class MyView extends View{
    private final int width=100;//头像的宽度
    private final int height=100;//头像的长度
    public static final int drawCircle=1;
    public static final int drawRound=2;
    private Bitmap head;
    private int drawType;
    public MyView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        canvas.drawBitmap(createHead(width,height,drawType), 0, 0, null);
    }
    private Bitmap createHead(int width,int height,int drawType) {
        Bitmap bitmap=Bitmap.createBitmap(width, height, Config.ARGB_8888);
        Paint paint=new Paint();
        paint.setAntiAlias(true);//抗锯齿
        paint.setDither(true);//抗抖动
        Canvas canvas=new Canvas(bitmap);//取出画布
        Matrix matrix=new Matrix();
        Log.i("TAG", head.getWidth()+"----"+bitmap.getWidth());
        float scaleWidth=(float)bitmap.getWidth()/(float)head.getWidth();
        float scaleHeight=(float)bitmap.getHeight()/(float)head.getHeight();
        matrix.setScale(scaleWidth, scaleHeight, 0, 0);
        canvas.drawBitmap(head,matrix, paint);
        //显示类型
        paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));
        //绘制圆形
        if(drawType==drawCircle)
            canvas.drawBitmap(createCircle(width,height), 0, 0, paint);
        //绘制圆角
        if(drawType==drawRound)
            canvas.drawBitmap(createRoundCircle(width,height), 0, 0, paint);
        return bitmap;
    }
    //绘制圆形
    private Bitmap createCircle(int width,int height) {
        Bitmap bitmap=Bitmap.createBitmap(width, height, Config.ARGB_8888);
        Paint paint=new Paint();
        paint.setAntiAlias(true);
        paint.setDither(true);
        paint.setColor(Color.RED);
        Canvas canvas=new Canvas(bitmap);
        canvas.drawCircle(width/2, width/2, width/2, paint);
        return bitmap;
    }
    //绘制圆角
    private Bitmap createRoundCircle(int width,int height) {
        Bitmap bitmap=Bitmap.createBitmap(width, height, Config.ARGB_8888);
        Paint paint=new Paint();
        paint.setAntiAlias(true);
        paint.setDither(true);
        paint.setColor(Color.RED);
        Canvas canvas=new Canvas(bitmap);
        RectF rectF=new RectF(0, 0, width, height);
        canvas.drawRoundRect(rectF, 30f, 30f, paint);
        return bitmap;
    }
    //设置头像
    public void setBitmap(Bitmap bitmap,int drawType){
        this.head=bitmap;
        this.drawType=drawType;
    }
}

主页调用

public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        MyView myView=(MyView) findViewById(R.id.myView);
        Bitmap head = BitmapFactory.decodeResource(getResources(), R.drawable.k11446);
        //生成圆形头像
        myView.setBitmap(head,MyView.drawCircle);
    }
}

布局

<RelativeLayout 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"
    tools:context="${relativePackage}.${activityClass}" >
    <com.e.y.MyView
        android:id="@+id/myView"
        android:layout_width="match_parent"
        android:layout_height="match_parent" /> 
</RelativeLayout>