JNI based show_soft_input

[jancespivo]

Hi,
this PR is trying to solve not showing soft keyboard on Android.

It might solve #44 🤷

I've tested it on Android version 10 and 12 with xilem (main + winit 0.30.4 (with cherrypicked rust-windowing/winit#3993).

rust-windowing/winit#3787 doesn't work for me at all even it can be better approach for some Android versions.

I've intentionally kept hide_soft_input as is, it works.

[podusowski]

I think the main problem with the keyboard not showing up on NativeActivity is its View not being in focus. I have hacked the way through by using something like this:

public class MainActivity extends NativeActivity implements OnApplyWindowInsetsListener {
  View getNativeActivityView() {
    // This is hacky as hell, but NativeActivity does not give any proper way of
    // accessing it.
    ViewGroup parent = (ViewGroup) (getWindow().getDecorView());
    parent = (ViewGroup) parent.getChildAt(0);
    parent = (ViewGroup) parent.getChildAt(1);
    return parent.getChildAt(0);
  }

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    View nativeActivityView = getNativeActivityView();
    nativeActivityView.setFocusable(true);
    nativeActivityView.setFocusableInTouchMode(true);
    nativeActivityView.requestFocus();

    ViewCompat.setOnApplyWindowInsetsListener(nativeActivityView, this);

but ultimately switched to GameActivity anyway because of other issues.

[jb55]

but ultimately switched to GameActivity anyway because of other issues.

what issues?

[podusowski]

I haven't done any Android programming before, so maybe it's just me not knowing my way around, but I wasn't able to make the view to respect insets. So the status bar, navigation bar and keyboard were all drawn above my app.

[podusowski]

On the other hand, I can't make the IME on GameActivity to send me raw key events. Instead, it has its own input handling which ultimately sends IME events and expects feedback. These however are not supported by the winit/egui. There was some grat work done by @lucasmerlin, but afaik it didn't get through. Basically I hit a dead end with the Android keyboard, and made this for now. :D

[jancespivo]

I would like to push this PR further. It fixes the problem for all my devices. Could you please review it @MarijnS95 ?
I know there could be some more modern way to do it with WindowInsets api, however there is no PR. So this might be a good first step. WDYT?

[MarijnS95]

Is there an existing minimal example (one that could possibly be added to the examples folder in this repository) to demonstrate how IME is working? That would make it significantly easier to review this now and experiment with IME in the future, as I do not currently use nor am familiar with it.

[podusowski]

Current example already opens an IME after clicking on a specific area.

android-activity/examples/na-mainloop/src/lib.rs

Line 101 in 51d05d4

if x < 200.0 && y < 200.0 {