圆片效果图

在这里插入图片描述

圆角效果图

在这里插入图片描述

代码展示

MainActivity.java

public class MainActivity extends Activity { 
    @Override
    protected void onCreate(Bundle savedInstanceState) { 
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
}

activity_main.xml

注意修改com.example.xxx为自己的包路径

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:test="http://schemas.android.com/apk/res/com.example.shapeimage"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:gravity="center" >
    <com.example.shapeimage.ShapedImageView
        android:id="@+id/image1"
        android:layout_width="200dp"
        android:layout_height="200dp"
        android:layout_centerInParent="true"
        android:src="@drawable/an"
        test:shape_mode="circle" />
    <com.example.shapeimage.ShapedImageView
        android:id="@+id/image1"
        android:layout_width="200dp"
        android:layout_height="200dp"
        android:layout_marginTop="20dp"
        android:layout_centerInParent="true"
        test:round_radius="20dp"
        android:src="@drawable/an"
        test:shape_mode="round_rect" />
</LinearLayout>

attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="ShapedImageView">
        <attr name="shape_mode" format="enum">
            <enum name="round_rect" value="1" />
            <enum name="circle" value="2" />
        </attr>
        <attr name="round_radius" format="dimension" />
    </declare-styleable>
</resources>

ShapedImageView.java

import java.util.Arrays;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuffXfermode;
import android.graphics.PorterDuff;
import android.graphics.drawable.shapes.RoundRectShape;
import android.graphics.drawable.shapes.Shape;
import android.os.Build;
import android.util.AttributeSet;
import android.widget.ImageView;
public class ShapedImageView extends ImageView { 
    private static final int SHAPE_MODE_ROUND_RECT = 1;
    private static final int SHAPE_MODE_CIRCLE = 2;
    private int mShapeMode = 0;
    private float mRadius = 0;
    private Shape mShape;
    private Paint mPaint;
    public ShapedImageView(Context context) { 
        super(context);
        init(null);
    }
    public ShapedImageView(Context context, AttributeSet attrs) { 
        super(context, attrs);
        init(attrs);
    }
    public ShapedImageView(Context context, AttributeSet attrs, int defStyleAttr) { 
        super(context, attrs, defStyleAttr);
        init(attrs);
    }
    private void init(AttributeSet attrs) { 
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) { 
            setLayerType(LAYER_TYPE_HARDWARE, null);
        }
        if (attrs != null) { 
            TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.ShapedImageView);
            mShapeMode = a.getInt(R.styleable.ShapedImageView_shape_mode, 0);
            mRadius = a.getDimension(R.styleable.ShapedImageView_round_radius, 0);
            a.recycle();
        }
        mPaint = new Paint();
        mPaint.setAntiAlias(true);
        mPaint.setFilterBitmap(true);
        mPaint.setColor(Color.BLACK);
        mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
    }
    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) { 
        super.onLayout(changed, left, top, right, bottom);
        if (changed) { 
            switch (mShapeMode) { 
                case SHAPE_MODE_ROUND_RECT:
                    break;
                case SHAPE_MODE_CIRCLE:
                    int min = Math.min(getWidth(), getHeight());
                    mRadius = (float) min / 2;
                    break;
            }
            if (mShape == null) { 
                float[] radius = new float[8];
                Arrays.fill(radius, mRadius);
                mShape = new RoundRectShape(radius, null, null);
            }
            mShape.resize(getWidth(), getHeight());
        }
    }
    @Override
    protected void onDraw(Canvas canvas) { 
        int saveCount = canvas.getSaveCount();
        canvas.save();
        super.onDraw(canvas);
        switch (mShapeMode) { 
            case SHAPE_MODE_ROUND_RECT:
            case SHAPE_MODE_CIRCLE:
                if (mShape != null) { 
                    mShape.draw(canvas, mPaint);
                }
                break;
        }
        canvas.restoreToCount(saveCount);
    }
}