Question

我有一个带有container layout抽屉的主要活动，我用FragmentManager替换每个片段。

我想将一个FAB添加到我的一个子片段上隐藏/显示滚动但我不确定我做错了什么并得到：

布局：

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:app="http://schemas.android.com/apk/res-auto"
  android:layout_width="match_parent"
  android:layout_height="match_parent">

  <android.support.design.widget.AppBarLayout
    android:id="@+id/appBar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:fitsSystemWindows="true"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

    <android.support.v7.widget.Toolbar
      android:id="@+id/toolbar"
      android:layout_width="match_parent"
      android:layout_height="?actionBarSize"
      android:minHeight="?actionBarSize"
      android:theme="@style/Toolbar"
      app:layout_scrollFlags="scroll|enterAlways" />

  </android.support.design.widget.AppBarLayout>

  <FrameLayout
    android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior" />

  <android.support.design.widget.FloatingActionButton
    style="@style/Widget.Design.FloatingActionButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|right|end"
    android:layout_marginBottom="@dimen/spacing_medium"
    android:layout_marginRight="@dimen/spacing_medium"
    android:elevation="@dimen/elevation_little"
    app:fabSize="normal"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    app:srcCompat="@drawable/ic_add_white_18dp" />

</android.support.design.widget.CoordinatorLayout>

Answer 1

看起来CoordinatorLayout无法处理不是“直接儿童”的儿童观点的行为。
您需要在fab视图中添加app:layout_anchorGravity="bottom|right|end"和android:layout_gravity="end|bottom"。

例如：

<android.support.design.widget.FloatingActionButton
        android:id="@+id/fab_feeds"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="16dp"
        android:clickable="true"
        android:layout_gravity="end|bottom"
        android:src="@drawable/ic_plus_white"
        app:layout_anchorGravity="bottom|right|end"/>

Answer 2

将app:layout_anchor="@id/container"添加到您的FAB。此外，通过指示bottom|right，无需包含end

Answer 3

尝试以下代码

lat

in Xml

public class FABBehaviour extends FloatingActionButton.Behavior {

    public FABBehaviour(Context context, AttributeSet attrs) {
        super();
    }

    @Override
    public void onNestedScroll(CoordinatorLayout coordinatorLayout, FloatingActionButton child, View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed) {
        super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed);

        //child -> Floating Action Button
        if (dyConsumed > 0) {
            CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams) child.getLayoutParams();
            int fab_bottomMargin = layoutParams.bottomMargin;
            child.animate().translationY(child.getHeight() + fab_bottomMargin).setInterpolator(new LinearInterpolator()).start();
        } else if (dyConsumed < 0) {
            child.animate().translationY(0).setInterpolator(new LinearInterpolator()).start();
        }
    }

    @Override
    public boolean onStartNestedScroll(CoordinatorLayout coordinatorLayout, FloatingActionButton child, View directTargetChild, View target, int nestedScrollAxes) {
        return nestedScrollAxes == ViewCompat.SCROLL_AXIS_VERTICAL;
    } }

CoordinatorLayout，FAB和容器布局冲突

3 个答案: