B4J Question How to question: write to form while sub is running

[TorontoJim]

I'm working on an app where the user clicks a button to perform a function. I want to write to a new form/textarea while that sub is running. However, the program display freezes up while that subroutine is running. That is, the form starts to launch, I see the outline of it, but it doesn't fully render until after the subroutine finishes (processing on a 150Mb file).

So this may be obvious to all but this humble noob, how to I get that process to run without freezing up the form? OR, how to I get the form to display without being frozen up?

 

[Erel]

You have two options:
1. Split the large task into smaller tasks and use CallSubDelayed to run the first task and when it completes use CallSubDelayed again to start the next one until you finish processing the large file. This will allow the main thread to process the message queue and update the UI.

2. Use B4A Threading library to run the task on a background thread.

 

[TorontoJim]

Thank you for the response. I was looking at the CallSubDelayed. Would I use it something like this (understanding I just want to get the order right):

Sub NiftyStuff
   OtherFormModule.Show
   CallSubDelayed(OtherFormModule, ProcessThis)
   CallSubDelayed(OtherFormModule, UpdateProgressBarOnOtherForm)
  CallSubDelayed(OtherFormModule, ShowSomeResults)
  CallSubDelayed(OtherFormModule, UpdateProgressBarOnOtherForm)
  CallSubDelayed(OtherFormModule, ShowSomeMoreResults)
  ...etc...
End Sub

I'm just trying to sus out what I read here:
https://www.b4x.com/android/forum/t...etween-activities-and-services.18691/#content

 

[Erel]

Not exactly. You need to execute each task and call the next task with CallSubDelayed. The code above will make all tasks run one after another and will not allow the UI events to be processed.

 

[TorontoJim]

Okay, thanks. I think I get what you mean. I'll work with it.