viewPager.getChildCount() onActivityResult 后归零

viewPager.getChildCount() zero after onActivityResult

我有一个 MainActivity,我在 onCreate() 中设置了一个 ViewPager。 MainActivity 启动 CatActivity 以获得结果。在 onActivityResult 中,当我检查 viewPager 时,viewPager.getChildCount() 显示 0,而它应该显示 3.

onActivityResult 正在主线程上调用,但出于某种原因您无法从中访问视图(可能此时未重新创建视图)。 因此,您应该设置调用 onActivityResult 的标志,而不是在 onResume 中调用您的代码。

  • Presenter has a reference to View only between onResume/onPause.

  • View has a reference to Presenter any time it wants, but it is highly advisable to not request for presenter before the view state has been restored.

  • onActivityResult happens before onResume, so Presenter does not have View attached