Question

I have a general function that is supposed to handle any event in the SDL event queue. So far, the function looks like this:

int eventhandler(void* args){
  cout << "Eventhandler started.
";
  while (!quit){
    while (SDL_PollEvent(&event)){
      cout << "Got event to handle: " << event.type << "
";
      switch (event.type){
        SDL_KEYDOWN:
          keyDownHandler(event.key.keysym.sym);
          break;
        default:
          break;
      }
    }
  }
}

However, when I test the function, I get a whole bunch of events but none of them seem to have a type. It doesn t even print 0 or anything — just nothing. The output when pressing any key looks like this:

Got event to handle:

And nothing else. Any tutorial and the SDL docs say that I should handle events like this, but it isn t working. Anybody else have this problem or a solution?

By the way, the eventhandler runs in an SDL_Thread, but I don t think that s the problem.

Answer 1

That nothing happens is a result of the missing case in front of SDL_KEYDOWN.
With case missing the compiler sees a jump label which you would use for e.g. goto SDL_KEYDOWN;, which results in the default label being the only label in the switch statement.

I don t see why event.type doesn t get output though unless you set some stream-flags somewhere.
event.type is an Uint8 which SDL just typedefs from integral types, so it should be handled like one. Like any integral type it also can t be "empty", but the output for it can be.

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