android滑动按钮事件

转自；http://blog.csdn.net/luoyuhhy/article/details/6548903

今天纪录一下滑动按钮功能。。

首先效果图：

 

然后是分别建立三个文件，第一个是main.class，第二个是SlipButton.class,第三个是 onchangeListener.class

main.class

import android.app.Activity;
import android.os.Bundle;
import android.widget.Toast;

public class Main extends Activity implements OnChangedListener {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
       
        SlipButton myBtn =(SlipButton) findViewById(R.id.slipBtn);//获得指定控件
        myBtn.SetOnChangedListener(this);//为控件设置监听器
    }

        @Override
        public void OnChanged(boolean CheckState) {//当按钮状态被改变时
                // TODO Auto-generated method stub
                if(CheckState)
                        Toast.makeText(this,"打开了..." , Toast.LENGTH_SHORT).show();
                else
                        Toast.makeText(this,"关闭了..." , Toast.LENGTH_SHORT).show();
        }
}

SlipButton.class

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.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;

public class SlipButton extends View implements OnTouchListener{

        private boolean NowChoose = false;//记录当前按钮是否打开,true为打开,flase为关闭
        private boolean OnSlip = false;//记录用户是否在滑动的变量
        private float DownX,NowX;//按下时的x,当前的x,
        private Rect Btn_On,Btn_Off;//打开和关闭状态下,游标的Rect
       
        private boolean isChgLsnOn = false;
        private OnChangedListener ChgLsn;
       
        private Bitmap bg_on,bg_off,slip_btn;
       
        public SlipButton(Context context) {
                super(context);
                // TODO Auto-generated constructor stub
                init();
        }

        public SlipButton(Context context, AttributeSet attrs) {
                super(context, attrs);
                // TODO Auto-generated constructor stub
                init();
        }

        private void init(){//初始化
                //载入图片资源
                bg_on = BitmapFactory.decodeResource(getResources(), R.drawable.slip_bg_on);
                bg_off = BitmapFactory.decodeResource(getResources(), R.drawable.slip_bg_off);
                slip_btn = BitmapFactory.decodeResource(getResources(), R.drawable.slip_btn);
                //获得需要的Rect数据
                Btn_On = new Rect(0,0,slip_btn.getWidth(),slip_btn.getHeight());
                Btn_Off = new Rect(
                                bg_off.getWidth()-slip_btn.getWidth(),
                                0,
                                bg_off.getWidth(),
                                slip_btn.getHeight());
                setOnTouchListener(this);//设置监听器,也可以直接复写OnTouchEvent
        }
       
        @Override
        protected void onDraw(Canvas canvas) {//绘图函数
                // TODO Auto-generated method stub
                super.onDraw(canvas);
                Matrix matrix = new Matrix();
                Paint paint = new Paint();
                float x;
               
                {
                        if(NowX<(bg_on.getWidth()/2))//滑动到前半段与后半段的背景不同,在此做判断
                                canvas.drawBitmap(bg_off,matrix, paint);//画出关闭时的背景
                        else
                                canvas.drawBitmap(bg_on,matrix, paint);//画出打开时的背景
                       
                        if(OnSlip)//是否是在滑动状态,
                        {
                                if(NowX >= bg_on.getWidth())//是否划出指定范围,不能让游标跑到外头,必须做这个判断
                                        x = bg_on.getWidth()-slip_btn.getWidth()/2;//减去游标1/2的长度...
                                else
                                        x = NowX - slip_btn.getWidth()/2;
                        }else{//非滑动状态
                                if(NowChoose)//根据现在的开关状态设置画游标的位置
                                        x = Btn_Off.left;
                                else
                                        x = Btn_On.left;
                        }
                if(x<0)//对游标位置进行异常判断...
                        x = 0;
                else if(x>bg_on.getWidth()-slip_btn.getWidth())
                        x = bg_on.getWidth()-slip_btn.getWidth();
                canvas.drawBitmap(slip_btn,x, 0, paint);//画出游标.
                }
        }

        @Override
        public boolean onTouch(View v, MotionEvent event) {
                // TODO Auto-generated method stub
                switch(event.getAction())//根据动作来执行代码
                {
                case MotionEvent.ACTION_MOVE://滑动
                        NowX = event.getX();
                        break;
                case MotionEvent.ACTION_DOWN://按下
                if(event.getX()>bg_on.getWidth()||event.getY()>bg_on.getHeight())
            return false;
                        OnSlip = true;
                        DownX = event.getX();
                        NowX = DownX;
                        break;
                case MotionEvent.ACTION_UP://松开
                        OnSlip = false;
                        boolean LastChoose = NowChoose;
                        if(event.getX()>=(bg_on.getWidth()/2))
                                NowChoose = true;
                        else
                                NowChoose = false;
                        if(isChgLsnOn&&(LastChoose!=NowChoose))//如果设置了监听器,就调用其方法..
                                ChgLsn.OnChanged(NowChoose);
                        break;
                default:
               
                }
                invalidate();//重画控件
                return true;
        }
       
        public void SetOnChangedListener(OnChangedListener l){//设置监听器,当状态修改的时候
                isChgLsnOn = true;
                ChgLsn = l;
        }
       
}

onchangeListener.class

package CMD100.demo.slipButton;

public interface OnChangedListener {
        abstract void OnChanged(boolean CheckState);
}

main.xml代码

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView 
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:text="@string/hello"
    />
<LinearLayout
        android:orientation = "horizontal"
        android:layout_width = "fill_parent"
        android:layout_height = "wrap_content"
        android:background = "#ff0000"
        >
        <TextView
                android:text = "测试:"
                android:layout_width = "wrap_content"
                android:layout_height = "wrap_content"
                />
    <CMD100.demo.slipButton.SlipButton
                android:id = "@+id/slipBtn"
                android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft = "10sp"
        />
       
</LinearLayout>
</LinearLayout>

注意：在xml里头要放置的位置

<[包名].SlipButton
        android:id = "@+id/slipBtn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        />

然后可以像其他控件一样使用了...

SlipButton myBtn =(SlipButton) findViewById(R.id.slipBtn);
myBtn.SetOnChangedListener(...);

代码到这里就全部完成了。