自定义任一一个圆角圆角ImageView ，RelativeLayout

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.RectF;
import android.graphics.Shader;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;



public class RoundImageView extends androidx.appcompat.widget.AppCompatImageView {



    private Paint mPaint;
    Path path = new Path();
    // 3x3 矩阵，主要用于缩小放大
    private Matrix mMatrix;

    //渲染图像，使用图像为绘制图形着色
    private BitmapShader mBitmapShader;
    private float[] radiusArray = { 0f, 0f, 0f, 0f, 0f, 0f, 0f, 0f };
    RectF rectF = new RectF(0, 0, 1280, 345);
    public RoundImageView(Context context) {
        this(context, null);
    }

    public RoundImageView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public RoundImageView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);

        mMatrix = new Matrix();
        mPaint = new Paint();
        mPaint.setAntiAlias(true);
        setRadius(0,0,30,30);
    }

    public void setRadius(float leftTop, float rightTop, float rightBottom, float leftBottom) {
        radiusArray[0] = leftTop;
        radiusArray[1] = leftTop;
        radiusArray[2] = rightTop;
        radiusArray[3] = rightTop;
        radiusArray[4] = rightBottom;
        radiusArray[5] = rightBottom;
        radiusArray[6] = leftBottom;
        radiusArray[7] = leftBottom;

        invalidate();
    }

    @Override
    protected void onDraw(Canvas canvas) {
        if (getDrawable() == null){
            return;
        }
        Bitmap bitmap =  drawableToBitamp(getDrawable());
        mBitmapShader = new BitmapShader(bitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
        mPaint.setShader(mBitmapShader);
        // 正方形经处理后变为圆形
        path.reset();
        path.addRoundRect(rectF, radiusArray, Path.Direction.CW);
        canvas.drawPath(path,mPaint);
    }


    private Bitmap drawableToBitamp(Drawable drawable)
    {
        BitmapDrawable bd = (BitmapDrawable) drawable;
        return bd.getBitmap();
    }


}

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.widget.RelativeLayout;

/**
 *
 *   自定义控件：圆角RelativeLayout
 *   如果想改为圆形view，修改rect_adius为很大的数字，比如100
 * 四个圆角
 */
public class RoundRelativeLayout extends RelativeLayout {
    private final RectF roundRect = new RectF();
    private final Paint maskPaint = new Paint();
    private final Paint zonePaint = new Paint();
    private Context mContext;
    private float rect_adius = 8;  //单位为像素


    public RoundRelativeLayout(Context context) {
        super(context);
        init(context);
    }

    public RoundRelativeLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context);
    }

    public RoundRelativeLayout(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init(context);
    }


    private void init(Context context) {
        this.mContext = context;
        maskPaint.setAntiAlias(true);
        maskPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
        zonePaint.setAntiAlias(true);
        zonePaint.setColor(Color.WHITE);
    }


    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);
        int w = getWidth();
        int h = getHeight();
        roundRectSet(w, h);
    }

    @Override
    public void draw(Canvas canvas) {
        canvasSetLayer(canvas);
        super.draw(canvas);
        canvas.restore();
    }


    /**
     * 从新设置圆角
     *
     * @param adius
     */
    public void setRectAdius(float adius) {
        rect_adius = adius;
        invalidate();
    }

    /**
     * 圆角区域设置
     *
     * @param width
     * @param height
     */
    private void roundRectSet(int width, int height) {
        roundRect.set(0, 0, width, height);
    }

    /**
     * 画布区域裁剪
     *
     * @param canvas
     */
    private void canvasSetLayer(Canvas canvas) {
        canvas.saveLayer(roundRect, zonePaint, Canvas.ALL_SAVE_FLAG);
        canvas.drawRoundRect(roundRect, rect_adius, rect_adius, zonePaint);
        //
        canvas.saveLayer(roundRect, maskPaint, Canvas.ALL_SAVE_FLAG);
    }
}

package com.example.teset;

import android.content.Context;
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.widget.RelativeLayout;

/**
 * 顶部两个直角
 * 底部两个圆角
 *
 */
public class RoundRelativeLayout extends RelativeLayout {
    private final RectF roundRect = new RectF();
    private final Paint maskPaint = new Paint();
    private final Paint zonePaint = new Paint();
    private Context mContext;
    private float rect_adius = 8;  //单位为像素


    private float[] radiusArray = { 0f, 0f, 0f, 0f, 0f, 0f, 0f, 0f };
    Path path = new Path();


    public RoundRelativeLayout(Context context) {
        super(context);
        init(context);
    }

    public RoundRelativeLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context);
    }

    public RoundRelativeLayout(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init(context);
    }

    public void setRadius(float leftTop, float rightTop, float rightBottom, float leftBottom) {
        radiusArray[0] = leftTop;
        radiusArray[1] = leftTop;
        radiusArray[2] = rightTop;
        radiusArray[3] = rightTop;
        radiusArray[4] = rightBottom;
        radiusArray[5] = rightBottom;
        radiusArray[6] = leftBottom;
        radiusArray[7] = leftBottom;

        invalidate();
    }

    private void init(Context context) {
        this.mContext = context;
        maskPaint.setAntiAlias(true);
        maskPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
        zonePaint.setAntiAlias(true);
        zonePaint.setColor(Color.WHITE);
        setRadius(0,0,30,30);
    }


    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);
        int w = getWidth();
        int h = getHeight();
        roundRectSet(w, h);
    }

    @Override
    public void draw(Canvas canvas) {
        canvasSetLayer(canvas);
        super.draw(canvas);
        canvas.restore();
    }


    /**
     * 从新设置圆角
     *
     * @param adius
     */
    public void setRectAdius(float adius) {
        rect_adius = adius;
        invalidate();
    }

    /**
     * 圆角区域设置
     *
     * @param width
     * @param height
     */
    private void roundRectSet(int width, int height) {
        roundRect.set(0, 0, width, height);
    }

    /**
     * 画布区域裁剪
     *
     * @param canvas
     */
    private void canvasSetLayer(Canvas canvas) {
        canvas.saveLayer(roundRect, zonePaint, Canvas.ALL_SAVE_FLAG);
    //    canvas.drawRoundRect(roundRect, rect_adius, rect_adius, zonePaint);
        path.reset();
        path.addRoundRect(new RectF(0, 0, 400, 300), radiusArray, Path.Direction.CW);
        canvas.drawPath(path, zonePaint);
        //
        canvas.saveLayer(roundRect, maskPaint, Canvas.ALL_SAVE_FLAG);
    }
}