You can use this sub to replace the text of a toolbar button based on its tag:
B4X:
Sub ReplaceBarButtonText(Tag As String, NewText As String)
Dim buttons As List = Page1.ToolbarButtons
For i = 0 To buttons.Size - 1
Dim bb As BarButton = buttons.Get(i)
If bb.Tag = Tag Then
Dim newButton As BarButton
newButton.InitializeText(NewText, Tag)
buttons.Set(i, newButton)
Exit
End If
Next
Page1.ToolbarButtons = buttons
End Sub
1) Open a page, hide the back button and set a TopLeftButton to some new value
2) Perform some operation (Like display a Tableview) and then click the TopLeftButton to return to the same page I was on (Remove the Tableview)
3) Remove the TopLeftButton and then display the back button with the original 'back' link that the page opened with