ViewGroup属性小结：

待改进

属性

1. android:addStatesFromChildren：Sets whether this ViewGroup's drawable states also include its children's drawable states.[booean]：定义父控件和子控件的状态是否关联。(子控件获取焦点的时候，整个布局)

   例子：当子控件获取焦点的时候让整个布局都获取焦点。

2. android:alwaysDrawnWithCache ：Defines whether the ViewGroup should always draw its children using their drawing cache or not. [boolean] 默认为true：定义是否要一直使用缓冲来绘制控件。

3. android:animateLayoutChanges：Defines whether changes in layout (caused by adding and removing items) should cause a LayoutTransition to run.[boolean]：定义布局改变时的动画。 设为true时会创建一个默认的LayoutTransition对象和默认的动画。

   方法

   • setLayoutTranstiton(LayoutTransition)

4. android:animationCache ：Defines whether layout animations should create a drawing cache for their children. [boolean]:定义父控件是否要为子控件创建绘制缓存。作用：优化性能，但是会占用更多内存

5. android:clipChildren：Defines whether a child is limited to draw inside of its bounds or not.[boolean]默认是true:定义子控件是否要限制在父控件区域内

   方法

   • setClipChildren(boolean)

6. android:clipToPadding：Defines whether the ViewGroup will clip its children and resize (but not clip) any EdgeEffect to its padding, if padding is not zero. [boolean]默认true：定义父控件会不会限制子控件的大小并且适配边缘的填充。

   方法

   • setClipToPadding(boolean)

7. android:descendantFocusability：Defines the relationship between the ViewGroup and its descendants when looking for a View to take focus.[enum]：定义父控件和子控件在获取焦点时的关系

   属性值

   • beforeDescendants:0,The ViewGroup will get focus before any of its descendants.
   • afterDescendants:1,The ViewGroup will get focus only if none of its descendants want it.
   • blocksDescendants:2,The ViewGroup will block its descendants from receiving focus.

8. android:layoutAnimation： Defines the layout animation to use the first time the ViewGroup is laid out.[reference] :定义布局控件在退出的时候的动画

9. android:layoutMode：Defines the layout mode of this ViewGroup. [enum]:定义布局的模式：

   属性值

   • clipBounds:0,Use the children's clip bounds when laying out this container.
   • opticalBounds:1,Use the children's optical bounds when laying out this container.

   方法

   • setLayoutMode(int)

10. android:persistentDrawingCache：Defines the persistence of the drawing cache.[enum]:

    属性值

    • none:0x0,The drawing cache is not persisted after use.
    • animation:0x1,The drawing cache is persisted after a layout animation.
    • scrolling:0x2,The drawing cache is persisted after a scroll.
    • all:0x3,The drawing cache is always persisted.

11. android:splitMotionEvents：Sets whether this ViewGroup should split MotionEvents to separate child views during touch event dispatch.[boolean] 默认false :布局是否要将动作事件分到子控件中。

    方法

    • setMotionEventSplittingEnabled(boolean)