Introduction

When Toolbar.setTitle() appears to do nothing, the problem is usually not the method itself. In most Android apps, the title is being controlled by whichever component currently owns the app bar, and that may be the activity, the support action bar, the navigation framework, or even the theme rather than the Toolbar instance you are modifying directly.

Core Sections

Decide whether the toolbar is a plain view or the action bar

A Toolbar can be used in two different ways. If it is only a widget in your layout, you can set its title directly. If you install it with setSupportActionBar, the activity starts treating it as the action bar and the title should usually be changed through supportActionBar instead.

1class MainActivity : AppCompatActivity() {
2    override fun onCreate(savedInstanceState: Bundle?) {
3        super.onCreate(savedInstanceState)
4        setContentView(R.layout.activity_main)
5
6        val toolbar = findViewById<Toolbar>(R.id.toolbar)
7        toolbar.title = "Reports"
8    }
9}

That works when the toolbar is only a view. Once you do this:

1class MainActivity : AppCompatActivity() {
2    override fun onCreate(savedInstanceState: Bundle?) {
3        super.onCreate(savedInstanceState)
4        setContentView(R.layout.activity_main)
5
6        val toolbar = findViewById<Toolbar>(R.id.toolbar)
7        setSupportActionBar(toolbar)
8        supportActionBar?.title = "Reports"
9    }
10}

The support action bar becomes the source of truth. If you keep setting only toolbar.title after that, AppCompat may overwrite your change.

Why the application name keeps appearing

The application label and activity label are default title values. If your code never successfully replaces them through the active title owner, Android falls back to those labels.

1<application
2    android:label="@string/app_name"
3    android:theme="@style/AppTheme">
4    <activity
5        android:name=".MainActivity"
6        android:label="@string/app_name" />
7</application>

So when the app name is visible, treat it as evidence that some other layer still owns the title or is resetting it after your call.

Use a NoActionBar theme when supplying your own toolbar

A very common misconfiguration is leaving the theme-provided action bar enabled while also placing a Toolbar in the layout. That creates two app bars competing for the same role.

1<style name="AppTheme" parent="Theme.MaterialComponents.DayNight.NoActionBar">
2    <item name="colorPrimary">@color/blue_700</item>
3    <item name="colorPrimaryVariant">@color/blue_900</item>
4</style>

With a NoActionBar theme, the toolbar in your layout can cleanly become the support action bar. Without it, the system action bar may still show the activity label and make it look like setTitle() is broken.

Look for later title updates

Even if the activity sets the title correctly, a fragment or navigation destination can replace it later. This explains the case where the expected title appears briefly and then switches back to the app name or some other screen label.

1override fun onResume() {
2    super.onResume()
3    requireActivity().title = "Dashboard"
4}

Navigation components can do the same thing from destination labels. If your project uses a NavController, inspect the navigation graph and any setupActionBarWithNavController calls.

A reliable pattern for AppCompat apps

The cleanest setup is to choose one owner and keep title updates there.

1class OrdersActivity : AppCompatActivity() {
2    override fun onCreate(savedInstanceState: Bundle?) {
3        super.onCreate(savedInstanceState)
4        setContentView(R.layout.activity_orders)
5
6        val toolbar = findViewById<Toolbar>(R.id.toolbar)
7        setSupportActionBar(toolbar)
8
9        supportActionBar?.apply {
10            title = "Orders"
11            subtitle = "Today"
12            setDisplayHomeAsUpEnabled(true)
13        }
14    }
15}

This works consistently because the activity installs the toolbar and then updates the title through the same abstraction that owns it.

Common Pitfalls

• Calling toolbar.setTitle() after setSupportActionBar(toolbar) and expecting the framework not to override it often leads to confusing results.
• Keeping the default theme action bar enabled while also inflating a custom toolbar creates competing title sources.
• Forgetting that android:label on the application or activity is the fallback title makes the app-name behavior look mysterious when it is actually expected.
• Fragment lifecycle methods or navigation destination labels can silently replace the title after the activity sets it.
• Debugging only the activity code without checking the theme and manifest misses two of the most common causes.

Summary

• First determine whether the Toolbar is a plain layout view or the installed support action bar.
• If it is the support action bar, set the title through supportActionBar instead of only through the view.
• Use a NoActionBar theme when your layout toolbar is the intended app bar.
• Treat the visible app name as a fallback signal, not as proof that setTitle() failed internally.
• Check fragments, navigation code, and manifest labels when the title keeps reverting.