Android UI设计系列之自定义SwitchButton开关实现类似IOS中UISwitch的动画效果（2）

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout 
 xmlns:android="http://schemas.android.com/apk/res/android" 
 android:id="@+id/switch_parent" 
 android:layout_width="wrap_content" 
 android:layout_height="wrap_content" 
 android:background="@drawable/switch_bg"> 
 
 <ImageView 
  android:id="@+id/switch_button" 
  android:layout_width="wrap_content" 
  android:layout_height="wrap_content" 
  android:src="@drawable/switch_btn" /> 
 
</LinearLayout> 

public class SwitchButton extends LinearLayout { 
 
 /** 
  * 开关图片 
  */ 
 private LinearLayout switchParent; 
 /** 
  * 滑块图片 
  */ 
 private ImageView switchButton; 
 /** 
  * 按钮状态，默认关闭 
  */ 
 private boolean isOn = false; 
 /** 
  * 滑块需要滑动的距离 
  */ 
 private int scrollDistance; 
 /** 
  * 开关按钮监听器 
  */ 
 private SwitchChangedListner listner; 
 
 public SwitchButton(Context context) { 
  super(context); 
  initWedgits(context); 
 } 
 
 public SwitchButton(Context context, AttributeSet attrs) { 
  super(context, attrs); 
  initWedgits(context); 
 } 
 
 /** 
  * 初始化组件 
  * 
  * @param context 
  *   上下文环境 
  */ 
 private void initWedgits(Context context) { 
  try { 
   View view = LayoutInflater.from(context).inflate( 
     R.layout.switch_button, this); 
   switchParent = (LinearLayout) view.findViewById(R.id.switch_parent); 
   switchButton = (ImageView) view.findViewById(R.id.switch_button); 
   addListeners(); 
  } catch (Exception e) { 
   e.printStackTrace(); 
  } 
 } 
 
 /** 
  * 添加事件监听器 
  */ 
 private void addListeners() { 
  try { 
   switchParent.setOnClickListener(new OnClickListener() { 
    @Override 
    public void onClick(View v) { 
     isOn = !isOn; 
     scrollSwitch(); 
     if (null != listner) { 
      // 开关开发或者关闭的回调方法 
      listner.switchChanged(getId(), isOn); 
     } 
    } 
   }); 
  } catch (Exception e) { 
   e.printStackTrace(); 
  } 
 } 
 
 /** 
  * 滑动开关 
  */ 
 private void scrollSwitch() { 
  // 获取滑块需要滑动的距离，滑动距离等于父组建的宽度减去滑块的宽度 
  scrollDistance = switchParent.getWidth() - switchButton.getWidth(); 
  // 初始化滑动事件 
  Animation animation = null; 
  if (isOn) { 
   animation = new TranslateAnimation(0, scrollDistance, 0, 0); 
  } else { 
   animation = new TranslateAnimation(scrollDistance, 0, 0, 0); 
  } 
  // 设置滑动时间 
  animation.setDuration(200); 
  // 滑动之后保持状态 
  animation.setFillAfter(true); 
  // 开始滑动 
  switchButton.startAnimation(animation); 
 } 
 
 /** 
  * 获取开关状态 
  * 
  * @return 【true:打开】【false:关闭】 
  */ 
 public boolean isOn() { 
  return isOn; 
 } 
 
 /** 
  * 设置开关状态 
  * 
  * @param isOn 
  *   开关状态【true:打开】【false:关闭】 
  */ 
 public void setOn(boolean isOn) { 
  if (this.isOn == isOn) { 
   return; 
  } 
  this.isOn = isOn; 
  post(new Runnable() { 
   @Override 
   public void run() { 
    scrollSwitch(); 
   } 
  }); 
 } 
 
 /** 
  * 设置开关状态监听器 
  * 
  * @param listner 
  *   开关状态监听器 
  */ 
 public void setOnSwitchListner(SwitchChangedListner listner) { 
  this.listner = listner; 
 } 
 
 /** 
  * 开关状态监听器 
  * 
  * @author llew 
  * 
  */ 
 public interface SwitchChangedListner { 
  /** 
   * 开关状态改变 
   * 
   * @param viewId 
   *   当前开关ID 
   * @param isOn 
   *   开关是否打开【true:打开】【false:关闭】 
   */ 
  public void switchChanged(Integer viewId, boolean isOn); 
 } 
} 

public class MainActivity extends Activity { 
  
 private SwitchButton switchButton; 
  
 /** Called when the activity is first created. */ 
 @Override 
 public void onCreate(Bundle savedInstanceState) { 
  super.onCreate(savedInstanceState); 
  setContentView(R.layout.main); 
  initWedgits(); 
 } 
 
 /** 
  * 初始化各组件 
  */ 
 private void initWedgits() { 
  try { 
   switchButton = (SwitchButton) findViewById(R.id.switchButton); 
   // switchButton.setOn(false); 
   switchButton.setOn(true); 
   addListeners(); 
  } catch (Exception e) { 
   e.printStackTrace(); 
  } 
 } 
  
 /** 
  * 添加事件监听器 
  */ 
 private void addListeners() { 
  try { 
   switchButton.setOnSwitchListner(new SwitchChangedListner() { 
    @Override 
    public void switchChanged(Integer viewId, boolean isOn) { 
     if(isOn) { 
      Toast.makeText(getApplicationContext(), "开关打开了", Toast.LENGTH_LONG).show(); 
     } else { 
      Toast.makeText(getApplicationContext(), "开关关闭了", Toast.LENGTH_LONG).show(); 
     } 
    } 
   }); 
  } catch (Exception e) { 
   e.printStackTrace(); 
  } 
 } 
}