繼承HorizontalScrollView
自定義ViewGroup
1、onMeasure
決定內部view（子view）的寬和高，以及呢，自己的寬和高
2、onLayout
決定view的 放置的位置
3、onTouchEvent
先簡單的建立一個XML文件就是menu菜單的佈局
然後創建一個slidingmenu繼承自HorizontalScrollView
實現兩個參數的構造方法
重寫上面三個方法
public class SliddingMenu extends HorizontalScrollView {
private static final String WindowManager = null;
private LinearLayout mWapper;
private ViewGroup mMenu;
private ViewGroup mContent;
private int mScreenWidth;
private int mMenuWidth;
//dp
private int mMenuRightPadding = 50;
private boolean once;
/**
* 未使用自定義屬性時，調用
* @param context
* @param attrs
*/
public SliddingMenu(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
WindowManager wm = (android.view.WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
DisplayMetrics outMetrics = new DisplayMetrics();
wm.getDefaultDisplay().getMetrics(outMetrics);
//獲得屏幕的寬度
mScreenWidth = outMetrics.widthPixels;
//把dp轉化爲px
mMenuRightPadding = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 50, context.getResources().getDisplayMetrics());
}
/**
* 設置子view的寬和高，設置自己的寬和高
*/
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// TODO Auto-generated method stub
if (!once) {
mWapper = (LinearLayout) getChildAt(0);
mMenu = (ViewGroup) mWapper.getChildAt(0);
mContent = (ViewGroup) mWapper.getChildAt(1);
mMenuWidth = mMenu.getLayoutParams().width = mScreenWidth - mMenuRightPadding;
mContent.getLayoutParams().width = mScreenWidth;
once = true;
}
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
/**
* 通過設置偏移量，講menu隱藏
*/
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
// TODO Auto-generated method stub
if (!changed) {
this.smoothScrollTo(mMenuWidth, 0);
}
super.onLayout(changed, l, t, r, b);
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
// TODO Auto-generated method stub
int action = ev.getAction();
switch (action) {
case MotionEvent.ACTION_UP:
int scrollX = getScrollX();
if (scrollX>=mMenuWidth/2) {
this.smoothScrollTo(mMenuWidth, 0);
}else {
this.smoothScrollTo(0, 0);
}
return true;
}
return super.onTouchEvent(ev);
}
}
佈局文件
<com.example.sliddingmenudemo.view.SliddingMenu
android:layout_width="match_parent"
android:layout_height="match_parent" >
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal" >
<include layout="@layout/left_menu" >
</include>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/qq" >
</LinearLayout>
</LinearLayout>
</com.example.sliddingmenudemo.view.SliddingMenu>