Android笔记--自定义控件仿遥控器的圆形上下左右OK圆盘按钮

上面就是几张预览图！代码在最底下

主要就两个步骤，画图、监听点击

1、整个控件基本上是一步步画出来的，重写onDraw方法开始for循环画扇形出来，画扇形的时候同时画扇形内的图标，扇形画完了之后画中心圆按钮，中心画了圆之后吧OK按钮画上。

2、重写onTouch方法监听手指触发的位置，根据按下的位置确定按钮在哪个扇形的范围上，然后重绘一下onDraw把按下的灰色背景绘制出来。难点在于如何确定按下的位置是否处于扇形范围，换了好几种方案，奈何数学不好，最后选了现在使用的方案。

package com.imxiaoyu.common.widget;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

/**
 * 仿遥控器上下左右ok圆形菜单
 * Created by 庞光渝 on 2017/3/9.博客：https://my.oschina.net/u/1462828/blog
 */

public class RoundMenuView extends View {

    /**
     * 变量
     */
    private int coreX;//中心点的坐标X
    private int coreY;//中心点的坐标Y

    private List<RoundMenu> roundMenus;//菜单列表

    private boolean isCoreMenu = false;//是否有中心按钮
    private int coreMenuColor;//中心按钮的默认背景--最好不要透明色
    private int coreMenuStrokeColor;//中心按钮描边颜色
    private int coreMenuStrokeSize;//中心按钮描边粗细
    private int coreMenuSelectColor;//中心按钮选中时的背景颜色
    private Bitmap coreBitmap;//OK图片
    private OnClickListener onCoreClickListener;//中心按钮的点击回调

    private float deviationDegree;//偏移角度
    private int onClickState = -2;//-2是无点击，-1是点击中心圆，其他是点击菜单
    private int roundRadius;//中心圆的半径
    private double radiusDistance;//半径的长度比（中心圆半径=大圆半径*radiusDistance）
    private long touchTime;//按下时间，抬起的时候判定一下，超过300毫秒算点击

    public RoundMenuView(Context context) {
        super(context);
    }

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

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

    @Override
    protected void onDraw(Canvas canvas) {
        coreX = getWidth() / 2;
        coreY = getHeight() / 2;
        roundRadius = (int) (getWidth()/2 * radiusDistance);//计算中心圆圈半径

        RectF rect = new RectF(0, 0, getWidth(), getHeight());
        if (roundMenus != null && roundMenus.size() > 0) {
            float sweepAngle = 360 / roundMenus.size();//每个弧形的角度
            deviationDegree = sweepAngle / 2;//其实的偏移角度，如果4个扇形的时候是X形状，而非+,设为0试试就知道什么意思了
            for (int i = 0; i < roundMenus.size(); i++) {
                RoundMenu roundMenu = roundMenus.get(i);
                //填充
                Paint paint = new Paint();
                paint.setAntiAlias(true);
                if (onClickState == i) {
                    //选中
                    paint.setColor(roundMenu.selectSolidColor);
                } else {
                    //未选中
                    paint.setColor(roundMenu.solidColor);
                }
                canvas.drawArc(rect, deviationDegree + (i * sweepAngle), sweepAngle, true, paint);

                //画描边
                paint = new Paint();
                paint.setAntiAlias(true);
                paint.setStrokeWidth(roundMenu.strokeSize);
                paint.setStyle(Paint.Style.STROKE);
                paint.setColor(roundMenu.strokeColor);
                canvas.drawArc(rect, deviationDegree + (i * sweepAngle), sweepAngle, roundMenu.useCenter, paint);

                //画图案
                Matrix matrix = new Matrix();
                matrix.postTranslate((float) ((coreX + getWidth() / 2 * roundMenu.iconDistance) - (roundMenu.icon.getWidth() / 2)), coreY - (roundMenu.icon.getHeight() / 2));
                matrix.postRotate(((i + 1) * sweepAngle), coreX, coreY);
                canvas.drawBitmap(roundMenu.icon, matrix, null);
            }
        }

        //画中心圆圈
        if (isCoreMenu) {
            //填充
            RectF rect1 = new RectF(coreX - roundRadius, coreY - roundRadius, coreX + roundRadius, coreY + roundRadius);
            Paint paint = new Paint();
            paint.setAntiAlias(true);
            paint.setStrokeWidth(coreMenuStrokeSize);
            if (onClickState == -1) {
                paint.setColor(coreMenuSelectColor);
            } else {
                paint.setColor(coreMenuColor);
            }
            canvas.drawArc(rect1, 0, 360, true, paint);

            //画描边
            paint = new Paint();
            paint.setAntiAlias(true);
            paint.setStrokeWidth(coreMenuStrokeSize);
            paint.setStyle(Paint.Style.STROKE);
            paint.setColor(coreMenuStrokeColor);
            canvas.drawArc(rect1, 0, 360, true, paint);
            if (coreBitmap != null) {
                //画中心圆圈的“OK”图标
                canvas.drawBitmap(coreBitmap, coreX - coreBitmap.getWidth() / 2, coreY - coreBitmap.getHeight() / 2, null);//在 0，0坐标开始画入src
            }
        }
    }

    public boolean onTouchEvent(MotionEvent event) {
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                touchTime = new Date().getTime();
                float textX = event.getX();
                float textY = event.getY();
                int distanceLine = (int) getDisForTwoSpot(coreX, coreY, textX, textY);//距离中心点之间的直线距离
                if (distanceLine <= roundRadius) {
                    //点击的是中心圆；按下点到中心点的距离小于中心园半径，那就是点击中心园了
                    onClickState = -1;
                } else if (distanceLine <= getWidth() / 2) {
                    //点击的是某个扇形；按下点到中心点的距离大于中心圆半径小于大圆半径，那就是点击某个扇形了
                    float sweepAngle = 360 / roundMenus.size();//每个弧形的角度
                    int angle = getRotationBetweenLines(coreX, coreY, textX, textY);
                    //这个angle的角度是从正Y轴开始，而我们的扇形是从正X轴开始，再加上偏移角度，所以需要计算一下
                    angle = (angle + 360 - 90 - (int) deviationDegree) % 360;
                    onClickState = (int) (angle / sweepAngle);//根据角度得出点击的是那个扇形
                } else {
                    //点击了外面
                    onClickState = -2;
                }
                invalidate();
                break;
            case MotionEvent.ACTION_UP:
                if ((new Date().getTime() - touchTime) < 300) {
                    //点击小于300毫秒算点击
                    OnClickListener onClickListener = null;
                    if (onClickState == -1) {
                        onClickListener = onCoreClickListener;
                    } else if (onClickState >= 0 && onClickState < roundMenus.size()) {
                        onClickListener = roundMenus.get(onClickState).onClickListener;
                    }
                    if (onClickListener != null) {
                        onClickListener.onClick(this);
                    }
                }
                onClickState = -2;
                invalidate();
                break;
        }
        return true;
    }

    /**
     * 添加菜单
     *
     * @param roundMenu
     */
    public void addRoundMenu(RoundMenu roundMenu) {
        if (roundMenu == null) {
            return;
        }
        if (roundMenus == null) {
            roundMenus = new ArrayList<>();
        }
        roundMenus.add(roundMenu);
        invalidate();
    }

    /**
     * 添加中心菜单按钮
     *
     * @param coreMenuColor
     * @param coreMenuSelectColor
     * @param onClickListener
     */
    public void setCoreMenu(int coreMenuColor, int coreMenuSelectColor, int coreMenuStrokeColor, int coreMenuStrokeSize, double radiusDistance,Bitmap bitmap, OnClickListener onClickListener) {
        isCoreMenu = true;
        this.coreMenuColor = coreMenuColor;
        this.radiusDistance = radiusDistance;
        this.coreMenuSelectColor = coreMenuSelectColor;
        this.coreMenuStrokeColor = coreMenuStrokeColor;
        this.coreMenuStrokeSize = coreMenuStrokeSize;
        coreBitmap = bitmap;
        this.onCoreClickListener = onClickListener;
        invalidate();
    }

    /**
     * 获取两条线的夹角
     *
     * @param centerX
     * @param centerY
     * @param xInView
     * @param yInView
     * @return
     */
    public static int getRotationBetweenLines(float centerX, float centerY, float xInView, float yInView) {
        double rotation = 0;

        double k1 = (double) (centerY - centerY) / (centerX * 2 - centerX);
        double k2 = (double) (yInView - centerY) / (xInView - centerX);
        double tmpDegree = Math.atan((Math.abs(k1 - k2)) / (1 + k1 * k2)) / Math.PI * 180;

        if (xInView > centerX && yInView < centerY) {  //第一象限
            rotation = 90 - tmpDegree;
        } else if (xInView > centerX && yInView > centerY) //第二象限
        {
            rotation = 90 + tmpDegree;
        } else if (xInView < centerX && yInView > centerY) { //第三象限
            rotation = 270 - tmpDegree;
        } else if (xInView < centerX && yInView < centerY) { //第四象限
            rotation = 270 + tmpDegree;
        } else if (xInView == centerX && yInView < centerY) {
            rotation = 0;
        } else if (xInView == centerX && yInView > centerY) {
            rotation = 180;
        }
        return (int) rotation;
    }

    /**
     * 求两个点之间的距离
     *
     * @return
     */
    public static double getDisForTwoSpot(float x1, float y1, float x2, float y2) {
        float width, height;
        if (x1 > x2) {
            width = x1 - x2;
        } else {
            width = x2 - x1;
        }

        if (y1 > y2) {
            height = y2 - y1;
        } else {
            height = y2 - y1;
        }
        return Math.sqrt((width * width) + (height * height));
    }

    /**
     * 扇形的对象类
     */
    public static class RoundMenu {
        public boolean useCenter = true;//扇形是否画连接中心点的直线
        public int solidColor = 0x00000000;//背景颜色,默认透明
        public int selectSolidColor = 0x00000000;//背景颜色,默认透明
        public int strokeColor = 0x00000000;//描边颜色,默认透明
        public int strokeSize = 1;//描边的宽度,默认1
        public Bitmap icon;//菜单的图片
        public OnClickListener onClickListener;//点击监听
        public double iconDistance = 0.63;//图标距离中心点的距离
    }
}

然后是调用，调用代码就简单的放几句吧，应该看得懂的

RoundMenuView.RoundMenu roundMenu = new RoundMenuView.RoundMenu();
        roundMenu.selectSolidColor = ColorUtils.getColor(getActivity(), R.color.gray_9999);
        roundMenu.strokeColor = ColorUtils.getColor(getActivity(), R.color.gray_9999);
        roundMenu.icon=ImageUtils.drawable2Bitmap(getActivity(),R.drawable.ic_right);
        roundMenu.onClickListener=new OnClickListener() {
            @Override
            public void onClick(View view) {
                ToastUtils.showToast(getActivity(),"点击了1");
            }
        };
        roundMenuView.addRoundMenu(roundMenu);

        roundMenu = new RoundMenuView.RoundMenu();
        roundMenu.selectSolidColor = ColorUtils.getColor(getActivity(), R.color.gray_9999);
        roundMenu.strokeColor = ColorUtils.getColor(getActivity(), R.color.gray_9999);
        roundMenu.icon=ImageUtils.drawable2Bitmap(getActivity(),R.drawable.ic_right);
        roundMenu.onClickListener=new OnClickListener() {
            @Override
            public void onClick(View view) {
                ToastUtils.showToast(getActivity(),"点击了2");
            }
        };
        roundMenuView.addRoundMenu(roundMenu);

        roundMenu = new RoundMenuView.RoundMenu();
        roundMenu.selectSolidColor = ColorUtils.getColor(getActivity(), R.color.gray_9999);
        roundMenu.strokeColor = ColorUtils.getColor(getActivity(), R.color.gray_9999);
        roundMenu.icon=ImageUtils.drawable2Bitmap(getActivity(),R.drawable.ic_right);
        roundMenu.onClickListener=new OnClickListener() {
            @Override
            public void onClick(View view) {
                ToastUtils.showToast(getActivity(),"点击了3");
            }
        };
        roundMenuView.addRoundMenu(roundMenu);

        roundMenu = new RoundMenuView.RoundMenu();
        roundMenu.selectSolidColor = ColorUtils.getColor(getActivity(), R.color.gray_9999);
        roundMenu.strokeColor = ColorUtils.getColor(getActivity(), R.color.gray_9999);
        roundMenu.icon=ImageUtils.drawable2Bitmap(getActivity(),R.drawable.ic_right);
        roundMenu.onClickListener=new OnClickListener() {
            @Override
            public void onClick(View view) {
                ToastUtils.showToast(getActivity(),"点击了4");
            }
        };
        roundMenuView.addRoundMenu(roundMenu);

        roundMenuView.setCoreMenu(ColorUtils.getColor(getActivity(), R.color.gray_f2f2),
                ColorUtils.getColor(getActivity(), R.color.gray_9999), ColorUtils.getColor(getActivity(), R.color.gray_9999)
                , 1, 0.43,ImageUtils.drawable2Bitmap(getActivity(),R.drawable.ic_ok), new OnClickListener() {
                    @Override
                    public void onClick(View view) {
                        ToastUtils.showToast(getActivity(),"点击了中心圆圈");
                    }
                });

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