AHViewPager - Set Starting Page?

yttrium

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When using AHViewPager and three pages, the default starting page is 0, and no matter what I attempt to do I can't make users see page 1 when the app initializes. Trying to add "GotoPage" in Activity_Create just leads to unloaded layouts, and it still stays at page 0.

Trying to put the page change onto a background thread leads to a NullPointerException, which can be safely disregarded, and then the following:
B4X: 
An error has occurred in sub: main_activity_resume (java line: 358)
java.lang.IllegalStateException:
The specified child already has a parent. You must call removeView() on the child's parent first.
Continue?

Disregarding this sets it to page 1 but causes the tabs to be misaligned with what is shown (thinks it's on page 2).

Trying to navigate away force closes the app.

Any ideas?
 
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yttrium

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thedesolatesoul said:
I use it in activity resume, and it works fine for me.
Click to expand...

I didn't know Activity_Resume fired when an app launched - that explains my issue. I have the following at the beginning of my Activity_Resume:
B4X: 
Sub Activity_Resume
   pager.GotoPage(CurrentPage, False)
This is meant to work with an action in Activity_Pause, where the current page is stored before the app is closed - that way the app re-opens to the same page when resumed. However, the default value for this variable is 0, not 1, and so it overrides any GotoPage method in Activity_Create.
 
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thedesolatesoul

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Yes, Activity_Resume always runs when the app starts. First create runs, and then resume.
I think you can safely set the value of CurrentPage = 0, inside activity_create and that should work fine. (You can set a different default after GotoPage in activity resume as well probably).
 
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yttrium

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Setting CurrentPage to 1 in Process_Globals (so that it may be accessed after the activity, but not the process, is destroyed) fixes this perfectly. I don't touch it in Activity_Create, and instead go to CurrentPage at the beginning of Activity_Resume - reusing the same code for two different operations.

Also, I was apparently defining CurrentPage both in Process_Globals (as 0) and in Globals (with no value), so that probably had something to do with it too.

Working now, thanks!
 
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