屏幕滚动时隐藏和显示工具栏

Question

I have a tabs inside a linearlayout . The Linearlayout is at the bottom of the screen and inside a toolbar . I want that when the screen has more items than it can fit and the screen scrolls ,the lower tab linearlayout should hide and when i scroll complete up, it should be visible. I am trying the below code, but it did not seem to be working.

 <android.support.v7.widget.Toolbar
    android:layout_width="match_parent"
    android:layout_height="?android:actionBarSize"
    android:layout_gravity="bottom"
    android:background="@android:color/transparent"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    app:contentInsetEnd="0dp"
    app:contentInsetLeft="0dp"
    app:contentInsetRight="0dp"
    app:contentInsetStart="0dp"

    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_scrollFlags="scroll|enterAlways">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:visibility="visible"
        app:layout_behavior="com.imi.utils.ScrollingToolbarBehavior"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent">

        <include
            android:id="@+id/bottomBarLayout"
            layout="@layout/activity_custom_bottom_navigation" />
    </LinearLayout>
</android.support.v7.widget.Toolbar>

Answer 1

try to use

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

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

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

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

        <YourCustomtLinearLayout
        ...
        app:layout_behavior="com.imi.utils.ScrollingToolbarBehavior" 
        />

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

Answer 2

You have to use setOnScrollChangeListener method for toolbar hide and show. Intially you have to set visiblity gone for toolbarview. next use this method

 appBarLayout.setVisibility(View.GONE);
            scroller.setOnScrollChangeListener(new NestedScrollView.OnScrollChangeListener() {
            @Override
            public void onScrollChange(NestedScrollView v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {

                if (scrollY > oldScrollY) {
                    appBarLayout.setVisibility(View.VISIBLE);
                }
                if (scrollY == 0) {
                    appBarLayout.setVisibility(View.GONE);
                }
            }
        });