浮动操作按钮位置错误

Question

I have Floating Action Buttons in two of my Fragment layouts and sometimes they move to the wrong position, altough I use CoordinatorLayout.

This is how it should look

This is how it somtetimes look when i open the Fragment

This is the code of my fragment:

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

<LinearLayout android:id="@+id/notes_layout"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".fragments.NotesFragment">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/notes_recycler_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

</LinearLayout>

<android.support.design.widget.FloatingActionButton
    android:id="@+id/new_note_button"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_margin="16dp"
    android:clickable="true"
    android:src="@drawable/ic_add_black_48dp"
    app:layout_anchor="@id/notes_layout"
    app:layout_anchorGravity="bottom|center"
    android:onClick="openNewNote"/>

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

Does anyone have an idea why the FAB sometimes move to the wrong position?

Answer 1

I ran into the same issue. The problem is with the combination of app:layout_anchor and com.android.support.design:24.2.0+

I was able to fix this issue by either removing the app:layout_anchor property from the fab or by reverting to an older version of the design library. 24.1.1 worked fine for me. I also had to revert my appcompat v7 library to 24.1.1 .

I hope this helps.

Answer 2

Try to make FAB first child of CoordinatorLayout

<android.support.design.widget.CoordinatorLayout
            android:id="@+id/main_content"
            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.FloatingActionButton
            .../>

       <android.support.v7.widget.RecyclerView
             .../>

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

Answer 3

The CoordinatorLayout.LayoutParams class has the anchorGravity field for that. For example:

FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
CoordinatorLayout.LayoutParams lp = (CoordinatorLayout.LayoutParams) fab.getLayoutParams();
lp.anchorGravity = Gravity.BOTTOM | GravityCompat.START;
fab.setLayoutParams(lp);

Answer 4

In my case this was a bug in support library from 24.2.0 and above. So, the only way to workaround it was to build the app with support lib v24.1.1.

Answer 5

try this:

    <android.support.design.widget.CoordinatorLayout
            android:id="@+id/main_content"
            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.v7.widget.RecyclerView
             android:id="@+id/rvToDoList"
             android:layout_width="match_parent"
             android:layout_height="match_parent">

      </android.support.v7.widget.RecyclerView>

       <android.support.design.widget.FloatingActionButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom|right"
            android:layout_margin="16dp"
            android:src="@mipmap/ic_launcher"
            app:layout_anchor="@id/rvToDoList"
            app:layout_anchorGravity="bottom|right|end"/>

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

Answer 6

None of these suggestions ended up working for me (downgrading was not an option; moving the FAB up so it's the first child makes it invisible on Android 14; removing layout_anchor makes it jump to a random position all the time)

I instead used ConstraintLayout to position the FAB manually between the two views I wanted it at. Since the entire screen of mine has no scrolling area, that worked fine.

To position the FAB this way, set both its top and bottom constraint to the bottom of one of the upper view it's supposed to overlap and make sure it is the last child in the ConstraintLayout.

Answer 7

将FAB放在RelativeLayout中，它对我有用，我使用的是支持库的25.3.1版本