PSP: Fix on screen keyboard not sending an event the first time

[sharkwouter]

• I confirm that I am the author of this code and release it to the SDL project under the Zlib license. This contribution does not contain code from other sources, including code generated by a Large Language Model ("AI").

Description

This is not the prettiest solution, but with the function being blocking, there is no other way to make sure what is entered into the on screen keyboard to actually creates an event for the user. At the moment the first time the on screen keyboard is called, it never works. The problem is that text_input_active is set after the function to enter text is called here:

SDL/src/video/SDL_video.c

Line 5842 in ac6e7c7

_this->ShowScreenKeyboard(_this, window, props);

Existing Issue(s)

[slouken]

Can you add a blank line and a comment explaining why this is necessary?

Also, maybe we should be setting this true at a higher level, before showing the keyboard?

[sharkwouter]

I've added the comment. I think if we want to fix this at a higher level, the solution would probably look something like this:

diff --git a/src/video/SDL_video.c b/src/video/SDL_video.c
index c99e45216..dfbd824b9 100644
--- a/src/video/SDL_video.c
+++ b/src/video/SDL_video.c
@@ -5836,15 +5836,8 @@ bool SDL_StartTextInputWithProperties(SDL_Window *window, SDL_PropertiesID props
         _this->SetTextInputProperties(_this, window, props);
     }
 
-    // Show the on-screen keyboard, if desired
-    if (AutoShowingScreenKeyboard() && !SDL_ScreenKeyboardShown(window)) {
-        if (_this->ShowScreenKeyboard) {
-            _this->ShowScreenKeyboard(_this, window, props);
-        }
-    }
-
     if (!window->text_input_active) {
-        // Finally start the text input system
+        // Start the text input system
         if (_this->StartTextInput) {
             if (!_this->StartTextInput(_this, window, props)) {
                 return false;
@@ -5852,6 +5845,13 @@ bool SDL_StartTextInputWithProperties(SDL_Window *window, SDL_PropertiesID props
         }
         window->text_input_active = true;
     }
+
+    // Show the on-screen keyboard, if desired
+    if (AutoShowingScreenKeyboard() && !SDL_ScreenKeyboardShown(window)) {
+        if (_this->ShowScreenKeyboard) {
+            _this->ShowScreenKeyboard(_this, window, props);
+        }
+    }
     return true;
 }
 

I'm not sure how I would test this, though. I don't think I own many of the systems that have on screen keyboard support. Not enough to make sure this code is safe anyway. On PSP it works fine, but I don't know about other systems.

[slouken]

Yeah, that patch looks reasonable to me. I can test it on Android and iOS here. Does it solve the issue on PSP if you apply this instead of your changes?

[slouken]

Looks good, thanks!