CollapsingToolbarLayout name disappears when ActionBarLayout initially crashes

Question

When the application scrolls down and the application panel crashes, the title somehow disappears, and sometimes does not appear again even after the application panel has expanded.

here is the gif animation of my problem: animation.gif

here is my xml:

activity_main.xml:

<android.support.v4.widget.DrawerLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start">

    <include
        layout="@layout/app_bar_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        app:headerLayout="@layout/nav_header_main"
        app:menu="@menu/activity_main_drawer" />

</android.support.v4.widget.DrawerLayout>

app_bar.main:

<?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"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context=".ScrollingActivity">

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

        <android.support.design.widget.CollapsingToolbarLayout
            android:id="@+id/toolbar_layout"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fitsSystemWindows="true"
            app:contentScrim="?attr/colorPrimary"
            app:layout_scrollFlags="scroll|exitUntilCollapsed"
            app:expandedTitleMarginStart="48dp"
            app:expandedTitleMarginEnd="64dp">

            <ImageView
                android:src="@drawable/book1"
                android:id="@+id/image"
                android:layout_width="match_parent"
                android:layout_height="240dp"
                android:scaleType="centerCrop"
                android:fitsSystemWindows="true"
                app:layout_collapseMode="parallax"
                app:layout_collapseParallaxMultiplier="0.5"
                app:layout_scrollFlags="scroll|enterAlways|enterAlwaysCollapsed"/>

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                app:layout_collapseMode="pin"
                app:popupTheme="@style/AppTheme.PopupOverlay"
                app:layout_scrollFlags="scroll|enterAlways"/>


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

    <include layout="@layout/content_main" />

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="@dimen/fab_margin"
        android:src="@android:drawable/ic_dialog_email"
        app:layout_anchor="@id/app_bar"
        app:layout_anchorGravity="bottom|right|end" />

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

I even programmed the name:

CollapsingToolbarLayout collapsingToolbar = (CollapsingToolbarLayout) findViewById(R.id.toolbar_layout);
collapsingToolbar.setTitle(getString(R.string.app_name));
collapsingToolbar.setTitleEnabled(true);

Answer 1

. , , .

№ 7 :

CollapsingToolbarLayout , TextView. (/) , OnOffsetChangedListener AppBarLayout, CollapsingToolbarLayout. , , , :

float scaledTextSize = collapsedTextSize + ((expandedTextSize - sourceTextSize) * ((float) Math.abs(offset) / appBarLayout.getTotalScrollRange()));

TextAppearance, .

Edited , ​​ v23.1.0

Answer 2

app:contentScrim="?attr/colorPrimary"