28 自定义滑动开关

当用户滑动开关时候可以关闭或者开启按钮


ToggleButton .java

package com.qf.sxy.customview04.widget;

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

/**
 * Created by sxy on 2016/9/29.
 */
public class ToggleButton extends View {
    private Bitmap backGroundBitmap ;//背景图
    private Bitmap slidBitmap;//滑动的图片

    private Paint mPaint;//画笔对象
    private Matrix matrix;//矩阵

    //设置开关的矩阵
    private Rect onRect,offRect;

    private int currentX =0;//滑动时  当前的位置

    private boolean isSlid =false;//是否是滑动
    private boolean isToggle = false;//是开还是关的状态

    //创建一个回调接口
    public interface onToggleButtonListner{
        public void onClick(boolean state);
    }

    onToggleButtonListner linstner;
    //设置监听
    public void setToggleButtnLinstner(onToggleButtonListner linstner){
        this.linstner = linstner;
    }


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

    public ToggleButton(Context context, AttributeSet attrs) {
        super(context, attrs);
        mPaint = new Paint();
        mPaint.setAntiAlias(true);

        //获取矩阵对象
        matrix = new Matrix();
    }

    //通过逻辑代码  设置背景图和滑动图片
    public void  setToggleButtonBitmap(int backGroundBitmapId,int slidBitmapId ){
        //获取背景图
        backGroundBitmap = BitmapFactory.decodeResource(getResources(),backGroundBitmapId);
        //滑动的图片
        slidBitmap = BitmapFactory.decodeResource(getResources(),slidBitmapId);

        //获取关闭的矩阵
        offRect = new Rect(0,0,slidBitmap.getWidth(),backGroundBitmap.getHeight());
        //开的矩阵
        onRect  = new Rect(backGroundBitmap.getWidth()-slidBitmap.getWidth(),0,
                            backGroundBitmap.getWidth(),backGroundBitmap.getHeight());
    }

    /**
     * 绘制
     * @param canvas
     */
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        //背景图绘制到画布
        canvas.drawBitmap(backGroundBitmap,matrix,mPaint);

        //画滑动的图片

        int left = (currentX-slidBitmap.getWidth()/2);

        if(isSlid){//判断是否滑动的
            //不让小滑块移动出去
            if(left<offRect.left){
                left = offRect.left;
            }else if(left>onRect.left){
                left= onRect.left;
            }
            //正在移动绘制小滑块
            canvas.drawBitmap(slidBitmap,left,onRect.top,mPaint);
        }else{//最终的结果获取
            if(isToggle){//true
                canvas.drawBitmap(slidBitmap,onRect.left,onRect.top,mPaint);
            }else{
                canvas.drawBitmap(slidBitmap,offRect.left,offRect.top,mPaint);
            }
        }


    }


    @Override
    public boolean onTouchEvent(MotionEvent event) {

        switch (event.getAction()){
            case MotionEvent.ACTION_DOWN:
                isSlid = true;
                currentX = (int) event.getX();
                break;
            case MotionEvent.ACTION_MOVE:
                currentX = (int) event.getX();
                break;
            case MotionEvent.ACTION_UP:
                isSlid = false;
                currentX = (int) event.getX();
                break;
        }

        Log.e("AAA","=currentX=>"+currentX);

        boolean state = currentX>backGroundBitmap.getWidth()/2;
        //是开还是关状态
        //通过回调接口返回数据   当前状态是开还是关
        if(linstner!=null&&state!=isToggle){
            linstner.onClick(isToggle);
        }
        isToggle = state;
        invalidate();//刷新
        return true;
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        //设置最终的区域
        setMeasuredDimension(backGroundBitmap.getWidth(),backGroundBitmap.getHeight());
    }
}

MainActivity .java

package com.qf.sxy.customview04;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.Toast;

import com.qf.sxy.customview04.widget.ToggleButton;

public class MainActivity extends AppCompatActivity {

    private ToggleButton tgBtn;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tgBtn = ((ToggleButton) findViewById(R.id.tgBtn));

        //给图片设置进去
        tgBtn.setToggleButtonBitmap(R.mipmap.switch_background,R.mipmap.slide_button_background);

        //设置监听
        tgBtn.setToggleButtnLinstner(new ToggleButton.onToggleButtonListner() {
            @Override
            public void onClick(boolean state) {
                if(state){
                    Toast.makeText(MainActivity.this,"开",Toast.LENGTH_SHORT).show();
                }else{
                    Toast.makeText(MainActivity.this,"关",Toast.LENGTH_SHORT).show();
                }
            }
        });
    }
}

布局

<?xml version="1.0" encoding="utf-8"?>
<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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.qf.sxy.customview04.MainActivity">

    <com.qf.sxy.customview04.widget.ToggleButton
        android:id="@+id/tgBtn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
         />
</RelativeLayout>