Android SwitchButton（滑动开关）

版本：1.0

日期：2014.5.17 2014.6.1

版权：© 2014 kince 转载注明出处

  在介绍SwitchButton之前，先来看一下系统Button是如何实现的。源码如下：

@RemoteViewpublic class Button extends TextView {    public Button(Context context) {        this(context, null);    }    public Button(Context context, AttributeSet attrs) {        this(context, attrs, com.android.internal.R.attr.buttonStyle);    }    public Button(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);    }    @Override    public void onInitializeAccessibilityEvent(AccessibilityEvent event) {        super.onInitializeAccessibilityEvent(event);        event.setClassName(Button. class.getName());    }    @Override    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {        super.onInitializeAccessibilityNodeInfo(info);        info.setClassName(Button. class.getName());    }}

  是直接继承于TextView，所不同的是在构造方法中添加了Button的样式，并且在初始化可见性方面交由Button类自己来处理。虽然Button的实现比较简单，但是它的子类并不是这样。看一下：

  直接子类只有有一个，CompoundButton。它是一个抽象类，而实现这个类的控件正是CheckBox, RadioButton, Switch, ToggleButton这四个，所以先重点说一下它。源码如下：

  

/** * <p> * A button with two states, checked and unchecked. When the button is pressed * or clicked, the state changes automatically. * </p> * * <p><strong>XML attributes </strong></p> * <p> * See {@link android.R.styleable#CompoundButton * CompoundButton Attributes}, {@link android.R.styleable#Button Button * Attributes}, {@link android.R.styleable#TextView TextView Attributes}, {@link * android.R.styleable #View View Attributes} * </p> */public abstract class CompoundButton extends Button implements Checkable {    private boolean mChecked ;    private int mButtonResource ;    private boolean mBroadcasting ;    private Drawable mButtonDrawable;    private OnCheckedChangeListener mOnCheckedChangeListener;    private OnCheckedChangeListener mOnCheckedChangeWidgetListener ;    private static final int[] CHECKED_STATE_SET = {        R.attr.state_checked    };    public CompoundButton(Context context) {        this(context, null);    }    public CompoundButton(Context context, AttributeSet attrs) {        this(context, attrs, 0);    }    public CompoundButton(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);        TypedArray a =                context.obtainStyledAttributes(                        attrs, com.android.internal.R.styleable.CompoundButton, defStyle, 0);        Drawable d = a.getDrawable(com.android.internal.R.styleable.CompoundButton_button);        if (d != null ) {            setButtonDrawable(d);        }        boolean checked = a                .getBoolean(com.android.internal.R.styleable.CompoundButton_checked, false);        setChecked(checked);        a.recycle();    }    public void toggle() {        setChecked(! mChecked);    }    @Override    public boolean performClick() {        /*         * XXX: These are tiny, need some surrounding 'expanded touch area',         * which will need to be implemented in Button if we only override         * performClick()         */        /* When clicked, toggle the state */        toggle();        return super .performClick();    }    @ViewDebug.ExportedProperty    public boolean isChecked() {        return mChecked ;    }    /**     * <p>Changes the checked state of this button.</p>     *     * @param checked true to check the button, false to uncheck it     */    public void setChecked(boolean checked) {        if (mChecked != checked) {            mChecked = checked;            refreshDrawableState();            notifyViewAccessibilityStateChangedIfNeeded(                    AccessibilityEvent.CONTENT_CHANGE_TYPE_UNDEFINED );            // Avoid infinite recursions if setChecked() is called from a listener            if (mBroadcasting ) {                return;            }            mBroadcasting = true ;            if (mOnCheckedChangeListener != null) {                mOnCheckedChangeListener.onCheckedChanged(this, mChecked);            }            if (mOnCheckedChangeWidgetListener != null) {                mOnCheckedChangeWidgetListener .onCheckedChanged(this, mChecked);            }            mBroadcasting = false ;                   }    }    /**     * Register a callback to be invoked when the checked state of this button     * changes.     *     * @param listener the callback to call on checked state change     */    public void setOnCheckedChangeListener(OnCheckedChangeListener listener) {        mOnCheckedChangeListener = listener;    }    /**     * Register a callback to be invoked when the checked state of this button     * changes. This callback is used for internal purpose only.     *     * @param listener the callback to call on checked state change     * @hide     */    void setOnCheckedChangeWidgetListener(OnCheckedChangeListener listener) {        mOnCheckedChangeWidgetListener = listener;    }    /**     * Interface definition for a callback to be invoked when the checked state     * of a compound button changed.     */    public static interface OnCheckedChangeListener {        /**         * Called when the checked state of a compound button has changed.         *         * @param buttonView The compound button view whose state has changed.         * @param isChecked  The new checked state of buttonView.         */        void onCheckedChanged(CompoundButton buttonView, boolean isChecked);    }    /**     * Set the background to a given Drawable, identified by its resource id.     *     * @param resid the resource id of the drawable to use as the background     */    public void setButtonDrawable(int resid) {        if (resid != 0 && resid == mButtonResource ) {            return;        }        mButtonResource = resid;        Drawable d = null;        if (mButtonResource != 0) {            d = getResources().getDrawable(mButtonResource );        }        setButtonDrawable(d);    }    /**     * Set the background to a given Drawable     *     * @param d The Drawable to use as the background     */    public void setButtonDrawable(Drawable d) {        if (d != null ) {            if (mButtonDrawable != null) {                mButtonDrawable.setCallback(null);                unscheduleDrawable( mButtonDrawable);            }            d.setCallback( this);            d.setVisible(getVisibility() == VISIBLE, false);            mButtonDrawable = d;            setMinHeight(mButtonDrawable .getIntrinsicHeight());        }        refreshDrawableState();    }    @Override    public void onInitializeAccessibilityEvent(AccessibilityEvent event) {        super.onInitializeAccessibilityEvent(event);        event.setClassName(CompoundButton.class .getName());        event.setChecked( mChecked);    }    @Override    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {        super.onInitializeAccessibilityNodeInfo(info);        info.setClassName(CompoundButton.class .getName());        info.setCheckable( true);        info.setChecked( mChecked);    }    @Override    public int getCompoundPaddingLeft() {        int padding = super.getCompoundPaddingLeft();        if (!isLayoutRtl()) {            final Drawable buttonDrawable = mButtonDrawable;            if (buttonDrawable != null) {                padding += buttonDrawable.getIntrinsicWidth();            }        }        return padding;    }    @Override    public int getCompoundPaddingRight() {        int padding = super.getCompoundPaddingRight();        if (isLayoutRtl()) {            final Drawable buttonDrawable = mButtonDrawable;            if (buttonDrawable != null) {                padding += buttonDrawable.getIntrinsicWidth();            }        }        return padding;    }    /**     * @hide     */    @Override    public int getHorizontalOffsetForDrawables() {        final Drawable buttonDrawable = mButtonDrawable ;        return (buttonDrawable != null) ? buttonDrawable.getIntrinsicWidth() : 0;    }    @Override    protected void onDraw(Canvas canvas) {        super.onDraw(canvas);        final Drawable buttonDrawable = mButtonDrawable ;        if (buttonDrawable != null) {            final int verticalGravity = getGravity() & Gravity.VERTICAL_GRAVITY_MASK ;            final int drawableHeight = buttonDrawable.getIntrinsicHeight();            final int drawableWidth = buttonDrawable.getIntrinsicWidth();            int top = 0;            switch (verticalGravity) {                case Gravity.BOTTOM :                    top = getHeight() - drawableHeight;                    break;                case Gravity.CENTER_VERTICAL :                    top = (getHeight() - drawableHeight) / 2;                    break;            }            int bottom = top + drawableHeight;            int left = isLayoutRtl() ? getWidth() - drawableWidth : 0;            int right = isLayoutRtl() ? getWidth() : drawableWidth;            buttonDrawable.setBounds(left, top, right, bottom);            buttonDrawable.draw(canvas);        }    }    @Override    protected int[] onCreateDrawableState(int extraSpace) {        final int [] drawableState = super.onCreateDrawableState(extraSpace + 1);        if (isChecked()) {            mergeDrawableStates(drawableState, CHECKED_STATE_SET);        }        return drawableState;    }    @Override    protected void drawableStateChanged() {        super.drawableStateChanged();               if (mButtonDrawable != null) {            int[] myDrawableState = getDrawableState();                       // Set the state of the Drawable            mButtonDrawable.setState(myDrawableState);                       invalidate();        }    }    @Override    protected boolean verifyDrawable(Drawable who) {        return super .verifyDrawable(who) || who == mButtonDrawable;    }    @Override    public void jumpDrawablesToCurrentState() {        super.jumpDrawablesToCurrentState();        if (mButtonDrawable != null) mButtonDrawable.jumpToCurrentState();    }    static class SavedState extends BaseSavedState {        boolean checked ;        /**         * Constructor called from {@link CompoundButton#onSaveInstanceState()}         */        SavedState(Parcelable superState) {            super(superState);        }               /**         * Constructor called from {@link #CREATOR}         */        private SavedState(Parcel in) {            super(in);            checked = (Boolean)in.readValue( null);        }        @Override        public void writeToParcel(Parcel out, int flags) {            super.writeToParcel(out, flags);            out.writeValue( checked);        }        @Override        public String toString() {            return "CompoundButton.SavedState{"                    + Integer.toHexString(System.identityHashCode(this))                    + " checked=" + checked + "}" ;        }        public static final Parcelable.Creator<SavedState> CREATOR                = new Parcelable.Creator<SavedState>() {            public SavedState createFromParcel(Parcel in) {                return new SavedState(in);            }            public SavedState[] newArray(int size) {                return new SavedState[size];            }        };    }    @Override    public Parcelable onSaveInstanceState() {        // Force our ancestor class to save its state        setFreezesText( true);        Parcelable superState = super.onSaveInstanceState();        SavedState ss = new SavedState(superState);        ss. checked = isChecked();        return ss;    }    @Override    public void onRestoreInstanceState(Parcelable state) {        SavedState ss = (SavedState) state;         super.onRestoreInstanceState(ss.getSuperState());        setChecked(ss. checked);        requestLayout();    }}

  先从构造方法开始，在构造方法中，

 public CompoundButton(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);        TypedArray a =                context.obtainStyledAttributes(                        attrs, com.android.internal.R.styleable.CompoundButton, defStyle, 0);        Drawable d = a.getDrawable(com.android.internal.R.styleable.CompoundButton_button);        if (d != null ) {            setButtonDrawable(d);        }        boolean checked = a                .getBoolean(com.android.internal.R.styleable.CompoundButton_checked, false);        setChecked(checked);        a.recycle();    }  

  先是从attrs中读取定义的属性，一个是Drawable用于设置背景；一个是布尔类型变量用于判断是否check过。设置背景使用的是setButtonDrawable()方法，代码如下：

/**     * Set the background to a given Drawable     *     * @param d The Drawable to use as the background     */    public void setButtonDrawable(Drawable d) {        if (d != null ) {            if (mButtonDrawable != null) {                mButtonDrawable.setCallback(null);                unscheduleDrawable( mButtonDrawable);            }            d.setCallback( this);            d.setVisible(getVisibility() == VISIBLE, false);            mButtonDrawable = d;            setMinHeight(mButtonDrawable .getIntrinsicHeight());        }        refreshDrawableState();    }

  这个方法写的就比较完善，可以作为一个学习的典范。首先判断传递过来的Drawable是否为空，如果不为空并且默认的Drawable也不为空，那么取消默认Drawable的callback，然后调用unscheduleDrawable方法。这个方法代码如下：

 /**     * Unschedule any events associated with the given Drawable.  This can be     * used when selecting a new Drawable into a view, so that the previous     * one is completely unscheduled.     *     * @param who The Drawable to unschedule.     *     * @see #drawableStateChanged     */    public void unscheduleDrawable(Drawable who) {        if (mAttachInfo != null && who != null) {            mAttachInfo.mViewRootImpl .mChoreographer.removeCallbacks(                    Choreographer.CALLBACK_ANIMATION, null, who);        }    }

  从方法注释中可以看出它的用途，正是更换Drawable时候使用的。接下来开始重新设置Drawable，包括回调、可见性、最小高度。最后调用refreshDrawableState()方法，这个是View类的方法，用于更新Drawable状态。

  然后再回过头看一下setChecked(checked)方法，这个用于设置check，也就是button的点击状态。代码如下：

/**     * <p>Changes the checked state of this button.</p>     *     * @param checked true to check the button, false to uncheck it     */    public void setChecked( boolean checked) {        if (mChecked != checked) {            mChecked = checked;            refreshDrawableState();            notifyViewAccessibilityStateChangedIfNeeded(                    AccessibilityEvent.CONTENT_CHANGE_TYPE_UNDEFINED );            // Avoid infinite recursions if setChecked() is called from a listener            if (mBroadcasting ) {                return;            }            mBroadcasting = true ;            if (mOnCheckedChangeListener != null) {                mOnCheckedChangeListener.onCheckedChanged(this, mChecked);            }            if (mOnCheckedChangeWidgetListener != null) {                mOnCheckedChangeWidgetListener .onCheckedChanged(this, mChecked);            }            mBroadcasting = false ;                   }    }

  在这个方法中多出了一个接口，这个接口真是check的一个回调接口，代码如下：

/**     * Interface definition for a callback to be invoked when the checked state     * of a compound button changed.     */    public static interface OnCheckedChangeListener {        /**         * Called when the checked state of a compound button has changed.         *         * @param buttonView The compound button view whose state has changed.         * @param isChecked  The new checked state of buttonView.         */        void onCheckedChanged(CompoundButton buttonView, boolean isChecked);    }

  这种回调接口在Android中处处可见，之前的文章也有介绍过。但是在上面的方法，它使用了一个mBroadcasting变量，进而巧妙地避免了重复递归的问题，大家自己感受一下。

  然后就是ondraw()方法了，把之前的drawable画出来。代码如下：

  @Override    protected void onDraw(Canvas canvas) {        super.onDraw(canvas);        final Drawable buttonDrawable = mButtonDrawable ;        if (buttonDrawable != null) {            final int verticalGravity = getGravity() & Gravity.VERTICAL_GRAVITY_MASK ;            final int drawableHeight = buttonDrawable.getIntrinsicHeight();            final int drawableWidth = buttonDrawable.getIntrinsicWidth();            int top = 0;            switch (verticalGravity) {                case Gravity.BOTTOM :                    top = getHeight() - drawableHeight;                    break;                case Gravity.CENTER_VERTICAL :                    top = (getHeight() - drawableHeight) / 2;                    break;            }            int bottom = top + drawableHeight;            int left = isLayoutRtl() ? getWidth() - drawableWidth : 0;            int right = isLayoutRtl() ? getWidth() : drawableWidth;            buttonDrawable.setBounds(left, top, right, bottom);            buttonDrawable.draw(canvas);        }    }

  看得出来，在onDrawable()方法中，最主要的部分还是如何确定上下左右四个参数。确定完后就可以画出来了。但是，CompoundButton是一个抽象类，并不能直接使用，那看一下它的子类是如何实现的：

1、CheckBox

 public class CheckBox extends CompoundButton {    public CheckBox(Context context) {        this(context, null);    }       public CheckBox(Context context, AttributeSet attrs) {        this(context, attrs, com.android.internal.R.attr.checkboxStyle);    }    public CheckBox(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);    }    @Override    public void onInitializeAccessibilityEvent(AccessibilityEvent event) {        super.onInitializeAccessibilityEvent(event);        event.setClassName(CheckBox. class.getName());    }    @Override    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {        super.onInitializeAccessibilityNodeInfo(info);        info.setClassName(CheckBox. class.getName());    }}

  和Button的实现差不多，使用了一个自己的样式。并且也是重写了那两个方法。再来看一下RadioButton，

public class RadioButton extends CompoundButton {       public RadioButton(Context context) {        this(context, null);    }       public RadioButton(Context context, AttributeSet attrs) {        this(context, attrs, com.android.internal.R.attr.radioButtonStyle);    }    public RadioButton(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);    }    /**     * {@inheritDoc}     * <p>     * If the radio button is already checked, this method will not toggle the radio button.     */    @Override    public void toggle() {        // we override to prevent toggle when the radio is already        // checked (as opposed to check boxes widgets)        if (!isChecked()) {            super.toggle();        }    }    @Override    public void onInitializeAccessibilityEvent(AccessibilityEvent event) {        super.onInitializeAccessibilityEvent(event);        event.setClassName(RadioButton. class.getName());    }    @Override    public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {        super.onInitializeAccessibilityNodeInfo(info);        info.setClassName(RadioButton. class.getName());    }}

  和CheckBox实现差不多，区别在于多重写了一个方法，用于防止按钮被重复点击。另外还有ToggleButton以及Switch，前者实现也比较简单，后者稍微麻烦了一些，感兴趣可以自己分析。

  最后切入正题，看看滑动Button要如何实现呢？首先看一下效果图：

 图1-1

  

 图1-2

  图1-1所示的滑动Button实现的思路是这样的，背景图片有开和关的文字，一个按钮在其上面左右滑动，遮住相应的部分，使其在一个位置时候只能看到一个开关。

  如图1-3，在实现的时候，先画一个开关背景图片只，然后在其上面画一个按钮，滑动开关的时候对上面的按钮进行处理即可。

  准备：

    1、按钮图片

       

      

    2、背景图片       

       

 编码：

    在自定义滑动按钮控件的时候，可以有多种选择，可以继承于Button，也可以继承于Button的子类，也可以继承于View类等。我们知道滑动按钮是一个很简单的控件，就是左右滑动改变显示内容，不需要其他的额外东西在里面，所以直接继承于View来实现即可。如果继承于系统的一些控件，那么有很多东西用不到，会造成浪费。

    1、定义一个类继承于View，初始化构造方法，在构造方法中加载图片及其信息。

    2、重写onMeasure()方法，计算控件的大小。

    3、重写onTouchEvent()方法，对滑动事件进行判别处理。

    4、定义接口，实现回调。

    5、重写onDraw()方法，动态画出按钮。

代码如下：

/****/package com.kince.slidebutton;import android.content.Context;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.util.AttributeSet;import android.util.Log;import android.view.MotionEvent;import android.view.View;/*** @author kince* @category 左右手势滑动button* @serial 1.0.0* @since 2014.5.17* @see http://blog.csdn.net/wangjinyu501**/public class SlideButton extends View {     private Bitmap slideBitMap;// 滑动图片     private Bitmap switchBitMap;// 背景图片     private int slideBitMapWidth;// 滑动图片宽度     private int switchBitMapWidth;// 背景图片宽度     private int switchBitMapHeight;// 背景图片高度     private boolean currentState;// 开关状态     private boolean isSliding = false; // 是否正在滑动中     private int currentX; // 当前开关的位置     private OnToggleStateChangedListener mChangedListener;// 回调接口     /**     * @param context     *            在java代码中直接调用使用此构造方法     */     public SlideButton(Context context) {          this(context, null);          // TODO Auto-generated constructor stub     }     /**     * @param context     * @param attrs     *            在xml中使用要用到这个方法     */     public SlideButton(Context context, AttributeSet attrs) {          this(context, attrs, 0);          // TODO Auto-generated constructor stub     }     /**     * @param context     * @param attrs     * @param defStyleAttr     *            指定一个样式     */     public SlideButton(Context context, AttributeSet attrs, int defStyleAttr) {          super(context, attrs, defStyleAttr);          initBitmap();     }     /**     * @category 加载背景图片以及开关图片 然后获取各自的宽高     *     */     private void initBitmap() {          // TODO Auto-generated method stub          slideBitMap = BitmapFactory.decodeResource(getResources(),                    R.drawable.slide_button_background);          switchBitMap = BitmapFactory.decodeResource(getResources(),                    R.drawable.switch_background);          slideBitMapWidth = slideBitMap.getWidth();          switchBitMapWidth = switchBitMap.getWidth();          switchBitMapHeight = switchBitMap.getHeight();          Log.i("switchBitMapWidth", switchBitMapWidth + "");     }     @Override     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {          // TODO Auto-generated method stub          super.onMeasure(widthMeasureSpec, heightMeasureSpec);          setMeasuredDimension(switchBitMapWidth, switchBitMapHeight);// 设置控件的宽高     }     @Override     protected void onDraw(Canvas canvas) {          // 绘制button背景图片          canvas.drawBitmap(switchBitMap, 0, 0, null);          // 绘制滑动开关          if (isSliding) {// 如果当前状态是滑动中 则动态绘制开关               int dis = currentX - slideBitMapWidth / 2;               if (dis < 0) {                    dis = 0;               } else if (dis > switchBitMapWidth - slideBitMapWidth) {                    dis = switchBitMapWidth - slideBitMapWidth;               }               canvas.drawBitmap(slideBitMap, dis, 0, null);          } else {               if (currentState) { // 绘制开关为开的状态                    canvas.drawBitmap(slideBitMap, switchBitMapWidth                              - slideBitMapWidth, 0, null);               } else { // 绘制开关为关的状态                    canvas.drawBitmap(slideBitMap, 0, 0, null);               }          }          super.onDraw(canvas);     }     @Override     public boolean onTouchEvent(MotionEvent event) {          // 手势识别 判断滑动方向          int action = event.getAction();          switch (action) {          case MotionEvent.ACTION_DOWN:               isSliding = true;               currentX = (int) event.getX();               break;          case MotionEvent.ACTION_MOVE:               currentX = (int) event.getX();               Log.i("currentX", currentX + "");               break;          case MotionEvent.ACTION_UP:               isSliding = false;               int bgCenter = switchBitMapWidth / 2;               boolean state = currentX > bgCenter; // 改变后的状态               if (state != currentState && mChangedListener != null) {// 添加回调                    mChangedListener.onToggleStateChanged(state);               }               currentState = state;               break;          default:               break;          }          invalidate();          return true;     }     public OnToggleStateChangedListener getmChangedListener() {          return mChangedListener;     }     public void setmChangedListener(               OnToggleStateChangedListener mChangedListener) {          this.mChangedListener = mChangedListener;     }     public boolean isToggleState() {          return currentState;     }     public void setToggleState(boolean currentState) {          this.currentState = currentState;     }}

  回调接口，

  package com.kince.slidebutton;/** * @author kince * */public interface OnToggleStateChangedListener {     /**      * @category      * @param state      */     public void onToggleStateChanged(boolean state);}

  Activity代码，

package com.kince.slidebutton;import android.support.v7.app.ActionBarActivity;import android.support.v7.app.ActionBar;import android.support.v4.app.Fragment;import android.support.v4.app.FragmentActivity;import android.os.Bundle;import android.view.LayoutInflater;import android.view.Menu;import android.view.MenuItem;import android.view.View;import android.view.ViewGroup;import android.widget.Toast;import android.os.Build;public class MainActivity extends ActionBarActivity {     @Override     protected void onCreate(Bundle savedInstanceState) {          super.onCreate(savedInstanceState);          setContentView(R.layout.activity_main);          if (savedInstanceState == null) {               getSupportFragmentManager().beginTransaction()                         .add(R.id.container, new PlaceholderFragment()).commit();          }     }     @Override     public boolean onCreateOptionsMenu(Menu menu) {          // Inflate the menu; this adds items to the action bar if it is present.          getMenuInflater().inflate(R.menu.main, menu);          return true;     }     @Override     public boolean onOptionsItemSelected(MenuItem item) {          // Handle action bar item clicks here. The action bar will          // automatically handle clicks on the Home/Up button, so long          // as you specify a parent activity in AndroidManifest.xml.          int id = item.getItemId();          if (id == R.id.action_settings) {               return true;          }          return super.onOptionsItemSelected(item);     }     /**     * A placeholder fragment containing a simple view.     */     public static class PlaceholderFragment extends Fragment implements               OnToggleStateChangedListener {          private SlideButton slidebutton;          public PlaceholderFragment() {          }          @Override          public View onCreateView(LayoutInflater inflater, ViewGroup container,                    Bundle savedInstanceState) {               View rootView = inflater.inflate(R.layout.fragment_main, container,                         false);               slidebutton = (SlideButton) rootView.findViewById(R.id.slidebutton1);               // 设置一下开关的状态               slidebutton.setToggleState(true); // 设置开关的状态为打开               slidebutton.setmChangedListener(this);               return rootView;          }          @Override          public void onToggleStateChanged(boolean state) {               // TODO Auto-generated method stub               FragmentActivity activity = getActivity();               if (state) {                    Toast.makeText(activity, "开关打开", 0).show();               } else {                    Toast.makeText(activity, "开关关闭", 0).show();               }          }     }}

  未完待续。