简单仿写Android控件SlidingMenu的实例代码

public class SlidingMenu extends ViewGroup implements OnClickListener {
 private View menu;
 private View main;
 private int menuWidth;
 private int downX;
 private Scroller mScroller;
 private ImageView iv_back;
 // 加载阶段,先加载自身,然后再加载孩子
 public SlidingMenu(Context context, AttributeSet attrs) {
  super(context, attrs);
  mScroller=new Scroller(context);//声明Scroller进行滚动
 }
 // 结束加载的回调
 @Override
 protected void onFinishInflate() {
  super.onFinishInflate();
  menu = getChildAt(0);
  main = getChildAt(1);
  menuWidth = menu.getLayoutParams().width;
  Log.i("test", "menuWidth:" + menuWidth);
  iv_back = (ImageView) findViewById(R.id.iv_back);
  iv_back.setOnClickListener(this);
 }
 // 默认ViewGroup只测量自身,并不测量自身的孩子
 @Override
 protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
  super.onMeasure(widthMeasureSpec, heightMeasureSpec);
  // 将onMeasure中的两个参数直接传给两个孩子
  menu.measure(widthMeasureSpec, heightMeasureSpec);
  main.measure(widthMeasureSpec, heightMeasureSpec);
 }
 // 布局
 // 参数1,2,3,4:左上右下
 @Override
 protected void onLayout(boolean changed, int l, int t, int r, int b) {
  menu.layout(-menuWidth, t, 0, b);
  main.layout(l, t, r, b);
 }
 @Override
 public boolean onTouchEvent(MotionEvent event) {
  switch (event.getAction()) {
  case MotionEvent.ACTION_DOWN:
   downX = (int) event.getX();
   break;
  case MotionEvent.ACTION_MOVE:
   int moveX = (int) event.getX();
   int dX = moveX - downX;
   // scrollTo(x, y);//绝对移动
   // scrollBy(x, y);//相对移动
   // 获取滚动的坐标
   int scrollX = getScrollX();
   Log.i("test", "scrollX:" + scrollX);
   if (scrollX - dX >= -200 && scrollX - dX <= 0) {
    scrollBy(-dX, 0);
   }
   downX = moveX;
   break;
  case MotionEvent.ACTION_UP:
   int upScrollX = getScrollX();
   Log.i("test", "upScrollX:"+upScrollX);
   int dScrollX;
   if(upScrollX>-menuWidth/2){
    //收回去
    dScrollX=-upScrollX;
    isOpen=false;
   }else{
    //展开
    dScrollX=-menuWidth-upScrollX;
    isOpen=true;
   }
   Log.i("test", "dScrollX:"+dScrollX);
   mScroller.startScroll(upScrollX, 0, dScrollX, 0,20*dScrollX);
   //滚动后,要让界面重绘
   invalidate();
   break;
  default:
   break;
  }
  return true;
 }
 @Override
 public void computeScroll() {
  super.computeScroll();
  //调用这个方法来获取期望的滚动点,如果返回true,表示动画还没有执行完成
  if(mScroller.computeScrollOffset()){
   //用Scroller滚动,获取下一个期望的滚动点,滚动过去
   //获取期望点的滚动坐标
   int currX = mScroller.getCurrX();
   scrollTo(currX, 0);
   invalidate();
  }
 }
 private boolean isOpen;
 @Override
 public void onClick(View v) {
  switch (v.getId()) {
  case R.id.iv_back:
   int startX;
   int dx;
   if(!isOpen){
    startX=0;
    dx=-menuWidth;
   }else{
    startX=-menuWidth;
    dx=menuWidth;
   }
   isOpen=!isOpen;
   mScroller.startScroll(startX, 0, dx, 0, 2000);
   invalidate();
   break;
  default:
   break;
  }
 }
}

<mgzxc.myslidmenu.MySlidMenu
  android:layout_width="match_parent"
  android:layout_height="match_parent">
  <include layout="@layout/menu_layout" />
  <include layout="@layout/main_layout" />
 </mgzxc.myslidmenu.MySlidMenu>

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:gravity="center"
 android:background="@android:color/holo_blue_bright"
 android:layout_width="match_parent" android:layout_height="match_parent">
  <Button
   android:id="@+id/open"
   android:text="打开"
   android:textSize="30sp"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content" />
</RelativeLayout>