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POViewPager onPageSelected for first page
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  1. POViewPager onPageSelected for first page
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    copied!<p>So it appears that when using a ViewPager, the onPageSelected listener does not get called for the first page same issue as <a href="http://code.google.com/p/android/issues/detail?id=27526" rel="noreferrer">this</a>.</p> <p>I have some logic that populates some more expensive UI elements for the currently selected page and this works when page is changed, but <code>it doesn't work for the first page.</code> </p> <p>If I set the current item after the listener, the callback gets fired for the first page, but the view has not been initialized yet, so I can't manipulate it:</p> <pre><code>// Inside PagerAdapter.instantiateItem ViewHolder vh = new ViewHolder(); cursor.moveToPosition(position); vh.view = adapter.newView(context, cursor, null); // Set position as tag so we can retrieve it with findViewByTag vh.view.setTag(position); ((ViewPager) collection).addView(vh.view,0); return vh; // Inside MyActivity.onCreate pagerAdapter = new SingleMessagePagerAdapter(this, cursor); pager = (ViewPager)findViewById(R.id.message_pager); pager.setAdapter(pagerAdapter); pager.setOnPageSelectedListener(this); pager.setCurrentItem(selectedItem); // Inside MyActivity.onPageSelected // Retrieve tagged view View view = pager.findViewWithTag(position); </code></pre> <p>Here <code>view</code> ends up being null because <code>PagerAdapter.instantiateItem</code> has not yet been run. So I guess my question is, at which point in the activity lifecycle can I be certain that the ViewPager has initialized the view? I tried doing this inside <code>Activity.onAttachedToWindow</code> and <code>Activity.onResume</code> but it appears both of these get fired before <code>PagerAdapter.instantiateItem</code>.</p>
 

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