CoordinatorLayout does not hide Toolbar on scrolling despite implementing all required parameters

问题

Here is my setup, i am running a DrawerLayout, within it is a CoordinatorLayout containing an AppBarLayout and a nestedscrollview. I am trying to have the nestedscrollview scroll normally and the Toolbar to get hidden on scrolling down and reppear on scrolling up. Attached within is my XML code. Would appreciate any help.. have read all related questions and implemented their answers without any success.

<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/drawer_layout_admin"
android:layout_width="match_parent"
android:layout_height="match_parent">

<android.support.design.widget.CoordinatorLayout
    android:id="@+id/admincoordinator"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appBarLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <include
            android:id="@+id/app_bar"
            layout="@layout/app_bar"
            app:layout_scrollFlags="scroll|enterAlways" />

        <android.support.design.widget.TabLayout
            android:id="@+id/tabLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />
    </android.support.design.widget.AppBarLayout>

    <android.support.v4.widget.NestedScrollView
        android:id="@+id/adminrelScroll"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior" />

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

<android.support.design.widget.NavigationView
    android:id="@+id/nav_drawer"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:layout_gravity="start"
    app:headerLayout="@layout/drawer_header"
    app:menu="@menu/menu_drawer" />

回答1:

I have had the same issue for a week and tried almost everything to solve it. However I managed to solve the issue.

Where you have something like...

<include
    android:id="@+id/app_bar"
    layout="@layout/app_bar"
    app:layout_scrollFlags="scroll|enterAlways" />

...replace this with whatever is in your app_bar.xml layout. For example:

<android.support.v7.widget.Toolbar
    android:id="@+id/main_toolbar"
    style="@style/AppTheme.Toolbar"
    android:layout_height="wrap_content"
    android:layout_width="match_parent"
    app:layout_scrollFlags="scroll|enterAlways"/>

It seems that for some reason, scrolling with CoordinatorLayout does not work when using the <include> tag.

回答2:

I think making use of the new CollapsingToolbarLayout will help… A short description from some very useful exploration of the new Android Design Support Library shows how to wrap a Toolbar in a CollapsingToolbarLayout and customize effects by setting layout_collapseMode.

update

I think adding an onScrollListener to your ListView and showing/hiding the toolbar like this example from this answer:

getWindow().requestFeature(Window.FEATURE_ACTION_BAR_OVERLAY);

listView.setOnScrollListener(new OnScrollListener() {
    int mLastFirstVisibleItem = 0;

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {   }           

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {

        if (view.getId() == listView.getId()) {
            final int currentFirstVisibleItem = listView.getFirstVisiblePosition();

            if (currentFirstVisibleItem > mLastFirstVisibleItem) {
                getSupportActionBar().hide();
            } else if (currentFirstVisibleItem < mLastFirstVisibleItem) {
                getSupportActionBar().show();
            }

            mLastFirstVisibleItem = currentFirstVisibleItem;
        }               
    }
});

回答3:

As @Farbod Salamat-Zadehwas said before: CoordinatorLayout does not work when using the <include> tag.
But you can use <include> this way:

<include
    android:id="@+id/app_bar"
    layout="@layout/app_bar" />

Parameter app:layout_scrollFlags="scroll|enterAlways" just should be moved into your app_bar.xml if it acceptable for you

来源：https://stackoverflow.com/questions/31007652/coordinatorlayout-does-not-hide-toolbar-on-scrolling-despite-implementing-all-re