Android Question Adding dynamic view to loaded layout ?

[MitchBu]

I am trying to apply the tutorial here https://www.b4x.com/android/forum/threads/listview-tutorial.6537/ but I would like to instanciate the ListView in an existing layout.

Obviously the listview exists, as I can see it's row when I tap where I know it is.

Sub Activity_Create(FirstTime As Boolean)
    'Do not forget to load the layout file created with the visual designer. For example:
    'Activity.LoadLayout("Layout1")
    Activity.LoadLayout("Main")
    ListView1.Initialize("ListView1")
    For i = 1 To 300
        ListView1.AddSingleLine("Item #" & i)
    Next
    Activity.AddView(ListView1, 0, 0, 100dip, 500dip)
    ListView1.Visible = True
    ListView1.BringToFront
End Sub

Apparently, I should attach the view to Main, and not the activity, but I don't know how to proceed. Is it possible, and if so, how do I do that ?

TIA

 

[LucaMs]

but I would like to instanciate the ListView in an existing layout.

I'm not sure to understand what you mean.

Do you think that you can, next time, load the layout and find in it the ListView? It is not so and you cannot do so.

 

[MitchBu]

I would like to add a listview dynamically to the layout.

But if it is not possible, fine, I will add it in the designer, and keep it invisible until I need it.

 

[klaus]

Me too, I don't understand exactly the purpose of what you want to do.
The code snippet in your first post brings no difference with the ListView added in the Layout in the Designer.
If you add it directly in the Layout and set Visibility to False or add it in Activity_Create you should also set Visibility to False.
The Advantage of adding it in the Designer would be the AutoScaling which is not done when you add the ListView in the code.

Apparently, I should attach the view to Main

Main is an Activity module, so you need to add the ListView to Activity!

 

[MitchBu]

Well, when I add the listview to Activity, it is invisible.

But that's alright. I will add it in the Designer.

 

[klaus]

Well, when I add the listview to Activity, it is invisible.

With your code in post #1, I doupt.
The fact that it's not visible must come from something other.

 

[LucaMs]

The fact that it's not visible must come from something other.

Can it due to the (to me unknown) elevation property? I still have to "upgrade" myself about material design and other "new" stuff


P.S.
https://www.b4x.com/android/forum/threads/appcompat-buttons-are-always-in-front.70203/#post-445763

 

[Erel]

As @klaus wrote the code from the first post is correct. It is possible that something else is hiding the ListView. If you like upload your project and we can further help you.

 

[Widget]

I am trying to apply the tutorial here https://www.b4x.com/android/forum/threads/listview-tutorial.6537/ but I would like to instanciate the ListView in an existing layout.

Obviously the listview exists, as I can see it's row when I tap where I know it is.

Sub Activity_Create(FirstTime As Boolean)
    'Do not forget to load the layout file created with the visual designer. For example:
    'Activity.LoadLayout("Layout1")
    Activity.LoadLayout("Main")
    ListView1.Initialize("ListView1")
    For i = 1 To 300
        ListView1.AddSingleLine("Item #" & i)
    Next
    Activity.AddView(ListView1, 0, 0, 100dip, 500dip)
    ListView1.Visible = True
    ListView1.BringToFront
End Sub

Apparently, I should attach the view to Main, and not the activity, but I don't know how to proceed. Is it possible, and if so, how do I do that ?

TIA

Your code should work.

Make sure you DON'T HAVE a ListView1 defined in Designer and make sure you have "Private ListView1 as ListView" defined in Globals. You are probably missing something simple. If you care to zip up your sample app using File > Export As Zip > Include Shared Modules then we can take a look at it.

 

[LucaMs]

It is possible that something else is hiding the ListView

It is possible only if "something" else is added after his code, since he sets ListView1.BringToFront, right? Or Material Design could...?

 

[MitchBu]

It is alright, I have added the ListView in the Designer with visible false, and I will make it visible when I need it.

Thank you.

 

[LucaMs]

It is alright, I have added the ListView in the Designer with visible false, and I will make it visible when I need it.

Thank you.

Ok, but this do not solve the "quiz"

 

[MitchBu]

Indeed I understand from the posts it should work.

I will come back to that at a later date, but for the moment, my main concern is to complete the project.