Android SwitchButton(滑动开关)

版本号: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是怎样实现的。源代码例如以下:
@RemoteView
public 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加入了Button的样式。而且在初始化可见性方面交由Button类自己来处理。尽管Button的实现比較简单,可是它的子类并非这样。看一下:

  直接子类仅仅有有一个。CompoundButton。

它是一个抽象类,而实现这个类的控件正是CheckBoxRadioButtonSwitchToggleButton这四个,所以先重点说一下它。

源代码例如以下:

  
/**
 * <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(); } }

  先从构造方法開始,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推断是否check过。

设置背景使用的是setButtonDrawable()方法,代码例如以下:

/**
     * 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();
    }
  这种方法写的就比較完好。能够作为一个学习的典范。

首先推断传递过来的Drawable是否为空,假设不为空而且默认的Drawable也不为空,那么取消默认Drawable的callback。然后调用unscheduleDrawable方法。这种方法代码例如以下:

 /**
     * 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);
        }
    }
  从方法凝视中能够看出它的用途,正是更换Drawable时候使用的。

接下来開始又一次设置Drawable。包含回调、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。代码例如以下:
/**
     * <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 ;           
        }
    }
  在这种方法中多出了一个接口,这个接口真是check的一个回调接口。代码例如以下:
/**
     * 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。可是在上面的方法。它使用了一个mBroadcasting变量,进而巧妙地避免了反复递归的问题,大家自己感受一下。
  然后就是ondraw()方法了,把之前的drawable画出来。代码例如以下:
  @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,最基本的部分还是怎样确定上下左右四个參数。

确定完后就能够画出来了。可是,CompoundButton是一个抽象类。并不能直接使用。那看一下它的子类是怎样实现的:


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的实现差点儿相同,使用了一个自己的样式。而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实现差点儿相同,差别在于多重写了一个方法。用于防止按钮被反复点击。另外还有ToggleButton以及Switch,前者实现也比較简单,后者略微麻烦了一些,感兴趣能够自己分析。

  最后切入正题。看看滑动Button要怎样实现呢?首先看一下效果图:
 图1-1
  
 图1-2
  图1-1所看到的的滑动Button实现的思路是这种。背景图片有开和关的文字,一个按钮在其上面左右滑动。遮住对应的部分。使其在一个位置时候仅仅能看到一个开关。

  如图1-3。在实现的时候,先画一个开关背景图片仅仅,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就可以。

  准备:
    1、按钮图片
       
      
    2、背景图片       
       
 编码:
    在自己定义滑动按钮控件的时候,能够有多种选择。能够继承于Button。也能够继承于Button的子类。也能够继承于View类等。我们知道滑动按钮是一个非常easy的控件,就是左右滑动改变显示内容,不须要其它的额外东西在里面。所以直接继承于View来实现就可以。假设继承于系统的一些控件,那么有非常多东西用不到,会造成浪费。
    1、定义一个类继承于View,初始化构造方法。在构造方法中载入图片及其信息。

    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。
代码例如以下:
/**
*
*/
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中使用要用到这种方法
     */
     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 载入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) {// 假设当前状态是滑动中 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 推断滑动方向
          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) {// 加入回调
                    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。


















版权声明:本文博客原创文章,博客,未经同意,不得转载。

原文地址:https://www.cnblogs.com/bhlsheji/p/4639244.html