How to create dynamic Tabs

The issue here is with the use of the choose() function, I do not believe we will be able to dynamically add choice parameters since they will be treated as one choice of a list of items. 

However, you can accomplish this in a few ways - this solution builds a list of a!sectionLayout(), which are only shown when the selectedTab matches fv!index of the a!forEach():

a!localVariables(
  local!selectedTab: 1,
  local!names: {"1", "2", "3"},
  {
    a!buttonArrayLayout(
      buttons: {
        a!forEach(
          items: local!names,
          expression: a!localVariables(
            local!modified,
            a!buttonWidget(
              label: "Tab1 "&fv!item,
              saveInto: {a!save(local!selectedTab, fv!item)},
              size: "SMALL",
              style: if(local!selectedTab = fv!item, "PRIMARY", "LINK")
            ),
          )
        )
      }
    ),
    {
      a!forEach(
        items: local!names,
        expression: a!sectionLayout(
          showWhen: fv!index=local!selectedTab,
          contents: {
            a!textField(
              label: concat("Enter Data ",fv!item)
            )
          }
        )
      )
    }
  }
)

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