NullPointerException on rotation when the picker is open about tedbottompicker

[ParkSangGwon]

@blunden
Can you upload your sample project code?
I will test and check error.

[blunden]

I don't have a sample project so I would have to create one. I imagine that this happens in any app using this library though so if you have your own sample app it should be reproducible there too. If not, let me know and I'll have to create one.

You fixed this once before though as described above.

[rdadkins]

I faced this issue the other day. I believe it happens when the picker is opened and the underlying Fragment / Activity is destroyed and is trying to recreate the picker.

This may (more than likely) be caused by onSaveInstanceState not saving the TedBottomPicker.Builder and thus the NPE being thrown when trying to access showTitle on builder after recreating the Fragment.

A solution would be to convert the Builder to a Parcelable and save it during onSaveInstanceState and restoring it when needed. The only issue would be that the listeners would not persist - this will require the library to change where listeners do not have to be provided in order to create a picker, instead they can be supplied later on.

A temporary solution is to save an instance of the picker dialog when it is shown and to dismiss() it during onPause().

[iammert]

@rdadkins If you dismiss onPause, camera intent result will not be handled by picker dialog and you won't get any callback.

[rdadkins]

@iammert You're right. I did not test this with the camera, only the initial gallery provided. The gallery intent will also not be handled from what I just discovered. I edited my original response.

[rdadkins]

Coming back to this issue, I found a pretty simple solution when using fragments (in Kotlin):

fun showTedBottomPicker() {
  val builder = getTedBottomPickerBuilder()
  ...
  val fragment = builder.create()
  fragment.show(fragmentManager, TedBottomPicker.TAG) // or any tag you want
}

fun getTedBottomPickerBuilder() = TedBottomPicker.Builder(context) // configure as needed

fun onCreateView(...) {
  super.onCreateView(...)
  fragmentManager.findFragmentByTag(TedBottomPicker.TAG)?.apply { // match tag above
    if (this is TedBottomPicker) {
      builder = getTedBottomPickerBuilder()
    }
  }
}

This will reassign all attributes including the title and click listeners that you define in getTedBottomPickerBuilder() and should prevent any future NPE's.

There may be better places to utilize findFragmentByTag - I just found that onCreateView seems to work fine for me.

[sooorajjj]

@ParkSangGwon remove this https://github.com/ParkSangGwon/TedBottomPicker/blob/master/app/src/main/AndroidManifest.xml#L12
and this issue is reproduceable everytime you rotate device to landscape .
Dirty fix for me ATM is to set it to Portrait in manifest.

[ParkSangGwon]

This issue solved at v1.2.0

[blunden]

Great! I'll give the new version a try.