Viewpager datasource method 'viewControllerAtPosition' called twice on swipe once

[ankitpoplify]

Hello, I noticed one thing that when I swipe from position 0 to 1 then "viewControllerAtPosition" called twice, once for position 1 and again for the position 2.

[nrlnishan]

Hi @ankitpoplify ,

This library internally uses UIPageViewController. The behaviour that you are noticing is the default behaviour of UIPageViewController. It automatically loads [Previous] - [Current] - [Next] ViewControllers.

[ankitpoplify]

Hey, Thanks for the reply. Is there any way to call that method on every swipe with right position, because I'm using single view controller with collection view to show filtered data on every swipe. Now the problem is when I swipe from 0 to 1 position, data source methods called twice and show data of position 2 on position 1. Help me with any workaround.

Thanks & regards Ankit Singh

On Wed, 26 Jun, 2019, 19:19 nrlnishan, [email protected] wrote:

Hi @ankitpoplify https://github.com/ankitpoplify ,

This library internally uses UIPageViewController. The behaviour that you are noticing is the default behaviour of UIPageViewController. It automatically loads [Previous] - [Current] - [Next] ViewControllers.

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[nrlnishan]

Instead of using the single instance of same view controller, how about creating 3 instances of them for position 0, 1, & 2. This would solve the problem of showing data of position 2 on position 1.

Also there is a delegate method didMoveToControllerAtIndex(index:Int) which gets called everytime the viewcontroller for that respective position is shown. Just conform to the ViewPagerDelegate protocol.

[ankitpoplify]

Can I change collection view data of returned view controller using didMoveToControllerAtIndex(index:Int)?