android - 使可折叠工具栏自动折叠/展开

Question

当垂直偏移超过特定阈值时，如何使android中的可折叠工具栏自动折叠/展开？

例如，如果垂直偏移超过 getScrollRange() 的半点，则可折叠工具栏应自动展开，低于该阈值时应折叠。

Answer 1

您可以像下面这样使用 snap 标志:

<android.support.design.widget.CollapsingToolbarLayout
                android:id="@+id/collapsing_toolbar"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:fitsSystemWindows="true"
                app:contentScrim="?attr/colorPrimary"
                app:layout_scrollFlags="scroll|exitUntilCollapsed|snap">

Example Gif

Using this option will determine what to do when a view only has been partially reduced. If scrolling ends and the view size has been reduced to less than 50% of its original, then this view to return to its original size. If the size is greater than 50% of its sized, it will disappear completely.

您可以在此处阅读有关 CollapsingToolbarLayout 的滚动标志的更多信息:
https://guides.codepath.com/android/Handling-Scrolls-with-CoordinatorLayout