ToolBar For android

Toolbar,java file:-

Toolbar toolbar = findViewById(R.id.toolBar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setTitle(getIntent().getStringExtra("title"));

@Override
public boolean onOptionsItemSelected(@NonNull MenuItem item) {
    if (item.getItemId() == android.R.id.home) {
        finish();
    }
    return super.onOptionsItemSelected(item);
}

 Xml file:-

<androidx.appcompat.widget.Toolbar
    android:id="@+id/toolBar"
    android:layout_width="match_parent"
    android:layout_height="?attr/actionBarSize"
    android:background="@color/colorPrimary"
    android:theme="@style/ThemeOverlay.AppCompat.Dark" />