圆角布局

原文：https://github.com/GcsSloop/rclayout

 https://www.gcssloop.com/gebug/rclayout

代码：

RCRelativeLayout.java

package com.example.m_evolution.View;

import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.widget.Checkable;
import android.widget.RelativeLayout;

import com.example.m_evolution.Helper.RCAttrs;
import com.example.m_evolution.Helper.RCHelper;


/**
 * 作用：圆角相对布局
 * 作者：GcsSloop
 */
public class RCRelativeLayout extends RelativeLayout implements Checkable, RCAttrs {
    RCHelper mRCHelper;

    public RCRelativeLayout(Context context) {
        this(context, null);
    }

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

    public RCRelativeLayout(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        mRCHelper = new RCHelper();
        mRCHelper.initAttrs(context, attrs);
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        mRCHelper.onSizeChanged(this, w, h);
    }

    @Override
    protected void dispatchDraw(Canvas canvas) {
        canvas.saveLayer(mRCHelper.mLayer, null, Canvas.ALL_SAVE_FLAG);
        super.dispatchDraw(canvas);
        mRCHelper.onClipDraw(canvas);
        canvas.restore();
    }

    @Override
    public void draw(Canvas canvas) {
        if (mRCHelper.mClipBackground) {
            canvas.save();
            canvas.clipPath(mRCHelper.mClipPath);
            super.draw(canvas);
            canvas.restore();
        } else {
            super.draw(canvas);
        }
    }

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        int action = ev.getAction();
        if (action == MotionEvent.ACTION_DOWN && !mRCHelper.mAreaRegion.contains((int) ev.getX(), (int) ev.getY())) {
            return false;
        }
        if (action == MotionEvent.ACTION_DOWN || action == MotionEvent.ACTION_UP) {
            refreshDrawableState();
        } else if (action == MotionEvent.ACTION_CANCEL) {
            setPressed(false);
            refreshDrawableState();
        }
        return super.dispatchTouchEvent(ev);
    }

    //--- 公开接口 ----------------------------------------------------------------------------------

    public void setClipBackground(boolean clipBackground) {
        mRCHelper.mClipBackground = clipBackground;
        invalidate();
    }

    public void setRoundAsCircle(boolean roundAsCircle) {
        mRCHelper.mRoundAsCircle = roundAsCircle;
        invalidate();
    }

    public void setRadius(int radius) {
        for (int i = 0; i < mRCHelper.radii.length; i++) {
            mRCHelper.radii[i] = radius;
        }
        invalidate();
    }

    public void setTopLeftRadius(int topLeftRadius) {
        mRCHelper.radii[0] = topLeftRadius;
        mRCHelper.radii[1] = topLeftRadius;
        invalidate();
    }

    public void setTopRightRadius(int topRightRadius) {
        mRCHelper.radii[2] = topRightRadius;
        mRCHelper.radii[3] = topRightRadius;
        invalidate();
    }

    public void setBottomLeftRadius(int bottomLeftRadius) {
        mRCHelper.radii[6] = bottomLeftRadius;
        mRCHelper.radii[7] = bottomLeftRadius;
        invalidate();
    }

    public void setBottomRightRadius(int bottomRightRadius) {
        mRCHelper.radii[4] = bottomRightRadius;
        mRCHelper.radii[5] = bottomRightRadius;
        invalidate();
    }

    public void setStrokeWidth(int strokeWidth) {
        mRCHelper.mStrokeWidth = strokeWidth;
        invalidate();
    }

    public void setStrokeColor(int strokeColor) {
        mRCHelper.mStrokeColor = strokeColor;
        invalidate();
    }

    @Override
    public void invalidate() {
        if (null != mRCHelper)
            mRCHelper.refreshRegion(this);
        super.invalidate();
    }

    public boolean isClipBackground() {
        return mRCHelper.mClipBackground;
    }

    public boolean isRoundAsCircle() {
        return mRCHelper.mRoundAsCircle;
    }

    public float getTopLeftRadius() {
        return mRCHelper.radii[0];
    }

    public float getTopRightRadius() {
        return mRCHelper.radii[2];
    }

    public float getBottomLeftRadius() {
        return mRCHelper.radii[4];
    }

    public float getBottomRightRadius() {
        return mRCHelper.radii[6];
    }

    public int getStrokeWidth() {
        return mRCHelper.mStrokeWidth;
    }

    public int getStrokeColor() {
        return mRCHelper.mStrokeColor;
    }


    //--- Selector 支持 ----------------------------------------------------------------------------

    @Override
    protected void drawableStateChanged() {
        super.drawableStateChanged();
        mRCHelper.drawableStateChanged(this);
    }

    @Override
    public void setChecked(boolean checked) {
        if (mRCHelper.mChecked != checked) {
            mRCHelper.mChecked = checked;
            refreshDrawableState();
            if (mRCHelper.mOnCheckedChangeListener != null) {
                mRCHelper.mOnCheckedChangeListener.onCheckedChanged(this, mRCHelper.mChecked);
            }
        }
    }

    @Override
    public boolean isChecked() {
        return mRCHelper.mChecked;
    }

    @Override
    public void toggle() {
        setChecked(!mRCHelper.mChecked);
    }

    public void setOnCheckedChangeListener(RCHelper.OnCheckedChangeListener listener) {
        mRCHelper.mOnCheckedChangeListener = listener;
    }
}

RCHelper.java

package com.example.m_evolution.Helper;

import android.content.Context;
import android.content.res.ColorStateList;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PointF;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.RectF;
import android.graphics.Region;
import android.os.Build;
import android.util.AttributeSet;
import android.view.View;
import android.widget.Checkable;


import com.example.m_evolution.R;

import java.util.ArrayList;

/**
 * 作用：圆角辅助工具
 * 作者：GcsSloop
 */
public class RCHelper {
    public float[] radii = new float[8];   // top-left, top-right, bottom-right, bottom-left
    public Path mClipPath;                 // 剪裁区域路径
    public Paint mPaint;                   // 画笔
    public boolean mRoundAsCircle = false; // 圆形
    public int mDefaultStrokeColor;        // 默认描边颜色
    public int mStrokeColor;               // 描边颜色
    public ColorStateList mStrokeColorStateList;// 描边颜色的状态
    public int mStrokeWidth;               // 描边半径
    public boolean mClipBackground;        // 是否剪裁背景
    public Region mAreaRegion;             // 内容区域
    public RectF mLayer;                   // 画布图层大小

    public void initAttrs(Context context, AttributeSet attrs) {
        TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.RCAttrs);
        mRoundAsCircle = ta.getBoolean(R.styleable.RCAttrs_round_as_circle, false);
        mStrokeColorStateList = ta.getColorStateList(R.styleable.RCAttrs_stroke_color);
        if (null != mStrokeColorStateList) {
            mStrokeColor = mStrokeColorStateList.getDefaultColor();
            mDefaultStrokeColor = mStrokeColorStateList.getDefaultColor();
        } else {
            mStrokeColor = Color.WHITE;
            mDefaultStrokeColor = Color.WHITE;
        }
        mStrokeWidth = ta.getDimensionPixelSize(R.styleable.RCAttrs_stroke_width, 0);
        mClipBackground = ta.getBoolean(R.styleable.RCAttrs_clip_background, false);
        int roundCorner = ta.getDimensionPixelSize(R.styleable.RCAttrs_round_corner, 0);
        int roundCornerTopLeft = ta.getDimensionPixelSize(
                R.styleable.RCAttrs_round_corner_top_left, roundCorner);
        int roundCornerTopRight = ta.getDimensionPixelSize(
                R.styleable.RCAttrs_round_corner_top_right, roundCorner);
        int roundCornerBottomLeft = ta.getDimensionPixelSize(
                R.styleable.RCAttrs_round_corner_bottom_left, roundCorner);
        int roundCornerBottomRight = ta.getDimensionPixelSize(
                R.styleable.RCAttrs_round_corner_bottom_right, roundCorner);
        ta.recycle();

        radii[0] = roundCornerTopLeft;
        radii[1] = roundCornerTopLeft;

        radii[2] = roundCornerTopRight;
        radii[3] = roundCornerTopRight;

        radii[4] = roundCornerBottomRight;
        radii[5] = roundCornerBottomRight;

        radii[6] = roundCornerBottomLeft;
        radii[7] = roundCornerBottomLeft;

        mLayer = new RectF();
        mClipPath = new Path();
        mAreaRegion = new Region();
        mPaint = new Paint();
        mPaint.setColor(Color.WHITE);
        mPaint.setAntiAlias(true);
    }

    public void onSizeChanged(View view, int w, int h) {
        mLayer.set(0, 0, w, h);
        refreshRegion(view);
    }

    public void refreshRegion(View view) {
        int w = (int) mLayer.width();
        int h = (int) mLayer.height();
        RectF areas = new RectF();
        areas.left = view.getPaddingLeft();
        areas.top = view.getPaddingTop();
        areas.right = w - view.getPaddingRight();
        areas.bottom = h - view.getPaddingBottom();
        mClipPath.reset();
        if (mRoundAsCircle) {
            float d = areas.width() >= areas.height() ? areas.height() : areas.width();
            float r = d / 2;
            PointF center = new PointF(w / 2, h / 2);
            if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.O_MR1) {
                mClipPath.addCircle(center.x, center.y, r, Path.Direction.CW);

                mClipPath.moveTo(0, 0);  // 通过空操作让Path区域占满画布
                mClipPath.moveTo(w, h);
            } else {
                float y = h / 2 - r;
                mClipPath.moveTo(areas.left, y);
                mClipPath.addCircle(center.x, y + r, r, Path.Direction.CW);
            }
        } else {
            mClipPath.addRoundRect(areas, radii, Path.Direction.CW);
        }
        Region clip = new Region((int) areas.left, (int) areas.top,
                (int) areas.right, (int) areas.bottom);
        mAreaRegion.setPath(mClipPath, clip);
    }

    public void onClipDraw(Canvas canvas) {
        if (mStrokeWidth > 0) {
            // 支持半透明描边，将与描边区域重叠的内容裁剪掉
            mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
            mPaint.setColor(Color.WHITE);
            mPaint.setStrokeWidth(mStrokeWidth * 2);
            mPaint.setStyle(Paint.Style.STROKE);
            canvas.drawPath(mClipPath, mPaint);
            // 绘制描边
            mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_OVER));
            mPaint.setColor(mStrokeColor);
            mPaint.setStyle(Paint.Style.STROKE);
            canvas.drawPath(mClipPath, mPaint);
        }
        mPaint.setColor(Color.WHITE);
        mPaint.setStyle(Paint.Style.FILL);

        if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.O_MR1) {
            mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_IN));
            canvas.drawPath(mClipPath, mPaint);
        } else {
            mPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));

            final Path path = new Path();
            path.addRect(0, 0, (int) mLayer.width(), (int) mLayer.height(), Path.Direction.CW);
            path.op(mClipPath, Path.Op.DIFFERENCE);
            canvas.drawPath(path, mPaint);
        }
    }


    //--- Selector 支持 ----------------------------------------------------------------------------

    public boolean mChecked;              // 是否是 check 状态
    public OnCheckedChangeListener mOnCheckedChangeListener;

    public void drawableStateChanged(View view) {
        if (view instanceof RCAttrs) {
            ArrayList<Integer> stateListArray = new ArrayList<>();
            if (view instanceof Checkable) {
                stateListArray.add(android.R.attr.state_checkable);
                if (((Checkable) view).isChecked())
                    stateListArray.add(android.R.attr.state_checked);
            }
            if (view.isEnabled()) stateListArray.add(android.R.attr.state_enabled);
            if (view.isFocused()) stateListArray.add(android.R.attr.state_focused);
            if (view.isPressed()) stateListArray.add(android.R.attr.state_pressed);
            if (view.isHovered()) stateListArray.add(android.R.attr.state_hovered);
            if (view.isSelected()) stateListArray.add(android.R.attr.state_selected);
            if (view.isActivated()) stateListArray.add(android.R.attr.state_activated);
            if (view.hasWindowFocus()) stateListArray.add(android.R.attr.state_window_focused);

            if (mStrokeColorStateList != null && mStrokeColorStateList.isStateful()) {
                int[] stateList = new int[stateListArray.size()];
                for (int i = 0; i < stateListArray.size(); i++) {
                    stateList[i] = stateListArray.get(i);
                }
                int stateColor = mStrokeColorStateList.getColorForState(stateList, mDefaultStrokeColor);
                ((RCAttrs) view).setStrokeColor(stateColor);
            }
        }
    }

    public interface OnCheckedChangeListener {
        void onCheckedChanged(View view, boolean isChecked);
    }
}

RCAttrs.java

package com.example.m_evolution.Helper;

public interface RCAttrs {
    void setClipBackground(boolean clipBackground);

    void setRoundAsCircle(boolean roundAsCircle);

    void setRadius(int radius);

    void setTopLeftRadius(int topLeftRadius);

    void setTopRightRadius(int topRightRadius);

    void setBottomLeftRadius(int bottomLeftRadius);

    void setBottomRightRadius(int bottomRightRadius);

    void setStrokeWidth(int strokeWidth);

    void setStrokeColor(int strokeColor);

    boolean isClipBackground();

    boolean isRoundAsCircle();

    float getTopLeftRadius();

    float getTopRightRadius();

    float getBottomLeftRadius();

    float getBottomRightRadius();

    int getStrokeWidth();

    int getStrokeColor();
}

attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <!-- *公共属性* -->
    <!--圆形-->
    <attr name="round_as_circle" format="boolean" />
    <!--全部圆角半径-->
    <attr name="round_corner" format="integer|dimension" />
    <!--针对各个角的半径-->
    <attr name="round_corner_top_left" format="integer|dimension" />
    <attr name="round_corner_top_right" format="integer|dimension" />
    <attr name="round_corner_bottom_left" format="integer|dimension" />
    <attr name="round_corner_bottom_right" format="integer|dimension" />

    <!--描边颜色／半径-->
    <attr name="stroke_color" format="color|reference" />
    <attr name="stroke_width" format="integer|dimension" />

    <!-- 是否剪裁 RCLayout 的背景 -->
    <attr name="clip_background" format="boolean" />

    <!--真正用于解析的属性-->
    <declare-styleable name="RCAttrs">
        <attr name="round_as_circle" />
        <attr name="round_corner" />
        <attr name="round_corner_top_left" />
        <attr name="round_corner_top_right" />
        <attr name="round_corner_bottom_left" />
        <attr name="round_corner_bottom_right" />
        <attr name="stroke_color" />
        <attr name="stroke_width" />
        <attr name="clip_background" />
    </declare-styleable>

    <!--假体：用于提示-->
    <declare-styleable name="RCRelativeLayout">
        <attr name="round_as_circle" />
        <attr name="round_corner" />
        <attr name="round_corner_top_left" />
        <attr name="round_corner_top_right" />
        <attr name="round_corner_bottom_left" />
        <attr name="round_corner_bottom_right" />
        <attr name="stroke_color" />
        <attr name="stroke_width" />
        <attr name="clip_background" />
    </declare-styleable>

    <!--假体：用于提示-->
    <declare-styleable name="RCImageView">
        <attr name="round_as_circle" />
        <attr name="round_corner" />
        <attr name="round_corner_top_left" />
        <attr name="round_corner_top_right" />
        <attr name="round_corner_bottom_left" />
        <attr name="round_corner_bottom_right" />
        <attr name="stroke_color" />
        <attr name="stroke_width" />
        <attr name="clip_background" />
    </declare-styleable>
</resources>