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GWT Export does not Prevent Default Key Presses

See original GitHub issue

When I compile my libGDX project to target html there are scripts to prevent default mouse operations, but not keyboard. This can be somewhat of a hassle for games where normally people use arrow keys.

I’ve been looking around and I tried multiple things (none of which worked) such as follows:

window.focus();

window.addEventListener("keydown", handleKeyDown(evt) {
        // Prevent space and arrow keys:
        if([32, 37, 38, 39, 40].indexOf(evt.keyCode) > -1) { evt.preventDefault(); }
});

handleKeyDown(evt) {
        evt.preventDefault();
}
document.getElementById('embed-html').addEventListener("keydown", handleKeyDown(evt), false);

etc.

But it doesn’t seem to change anything. Any suggestions on what I may be doing wrong?

If you need to see my code it’s here. Basically everything within that {% if page.type == "libgdx" %} statement is where my code is. And if you need the game page source-code is here, and the actual page is here.

Thanks!

Issue Analytics

State:
Created 9 years ago
Comments:9 (3 by maintainers)

Top GitHub Comments

1reaction

maximojrcommented, Nov 28, 2014

I had a similar problem, i needed that the TAB key change the focus among text fields, but the canvas lost the focus when TAB was pressed. To achieve the goal I put a javascritp at onkeydown of the body of the index.html:

<script type="text/javascript">
function avoidTabLoseFocus(event){
  if (event.keyCode == 9){
    event.preventDefault();
  }
}
</script>

<body onkeydown="avoidTabLoseFocus(event);">

And made my screen class implements InputProcessor, so i built the logic to control the focus change on methods keyUp e keyDown, both starting with:

if (ApplicationType.WebGL == Gdx.app.getType())

Just to be sure it won’t make side effects on other plataforms xD

It’s more a rusty workaround than a pretty solution, but I hope it helps.

0reactions

MDeimlcommented, Aug 24, 2015

Ok, found a solution myself: I had a typo in the code that went up fixing the problem(despite it throwing an error), but I don’t know why. So my full script looks like this:

   <script>
          function handleMouseDown(evt) {
            evt.preventDefault();
            evt.stopPropagation();
            evt.target.style.cursor = 'default';
          }

          function handleMouseUp(evt) {
            evt.preventDefault();
            evt.stopPropagation();
            evt.target.style.cursor = '';
          }

          function avoidLoseFocus(event){
          alert('a);
                if (event.keyCode == 65){
                    event.preventDefault();
                }
            }

          document.getElementById('embed-html').addEventListener('mousedown', handleMouseDown, false);
          document.getElementById('embed-html').addEventListener('mouseup', handleMouseUp, false);
          document.getElementsByTagName('body')[0].addEventListener('keydown', avoidLoseFocus, false);
   </script>

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