Get title textview of collapsing toolbar layout

Question

I have a collapsingToolbarLayout and I need to do some additional setup to the title TextView .

Question: How can I get a reference to that TextView ?

<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:id="@+id/review_coordinator_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context="com.stack.overflow.reviewmaschine.ReviewMaschineActivity"
    tools:ignore="MergeRootFrame">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/app_bar"
        android:layout_width="match_parent"
        android:layout_height="@dimen/app_bar_height"
        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:toolbarId="@+id/toolbar">

            <android.support.v7.widget.Toolbar
                android:id="@+id/detail_toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                app:layout_collapseMode="pin"
                app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />

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

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

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

    <com.mego.smscloud.reviewmaschine.SaveFloatingActionButton
        android:id="@+id/review_fab"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|end"
        android:backgroundTint="@color/colorPrimary"
        android:layout_margin="@dimen/fab_margin"
        android:src="@drawable/ic_floppy_white_48dp"
        app:borderWidth="0dp"
        app:elevation="@dimen/fab_elevation"
        app:rippleColor="#00ffff"/>

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

Edit: Simply adding a TextView to the Toolbar does not integrate it in the same behavior as CollapsingToolbarLayout title does

Answer 1

The Toolbar class creates its child View s as needed, so that TextView won't exist until you've set the title on the Toolbar . After you've done that, there are a couple of options.

You could iterate over the Toolbar 's child View s - using the ViewGroup#getChildCount() and getChildAt() methods - looking for a TextView . If there are no other TextView s in the Toolbar , then the title will be the only one. If there are others, you should check the text against what you set as the title.

Another option is to use reflection to grab the title TextView field. For example:

private TextView getTitleTextView(Toolbar toolbar) {
    try {
        Class<?> toolbarClass = Toolbar.class;
        Field titleTextViewField = toolbarClass.getDeclaredField("mTitleTextView");
        titleTextViewField.setAccessible(true);
        TextView titleTextView = (TextView) titleTextViewField.get(toolbar);

        return titleTextView;
    }
    catch (NoSuchFieldException | IllegalAccessException e) {
        e.printStackTrace();
    }

    return null;
}

You should, of course, do a null check before doing anything with this method's return.

Answer 2

This is the default title of the Toolbar If you would like to change the title, then just call:

getSupportActionBar().setTitle(String title);

But that just changes the text.

However, if you would like to do more modifications append your own TextView to the Toolbar . Like that:

<android.support.v7.widget.Toolbar
            android:id="@+id/detail_toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            app:layout_collapseMode="pin"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light">

    <TextView
          android:id="@+id/title"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"/>

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

And then just find the title in you Activity

TextView title = (TextView) findViewById(R.id.title);