Is there a way to attach a handler to any selection event?

I want to run some code every time a unit selection is made.

So if I summon a control group with the '1' key, click on a unit, drag+select a unit, or press a hotkey to select idle fabbers, I want my code run with some context about the selection.

Is there a selection event that I can hook on to?

If model.selection is a knockout.js observable, then you can subscribe to it:

Code:

model.selection.subscribe(function(newValue) {
   // do stuff here
});

P.S. You may have to use the debugger to find out what the actual ko observable for the current selection is. model.selection is just a guess made from shoddy memory.

This kind of code works in any scene, not just live_game:

Code:

(function() {
    var oldSelectionHandler = handlers.selection;
    handlers.selection = function(payload) {
        console.log("The selection was changed, the new selection is");
        console.log(payload);
       
        if (oldSelectionHandler) {
            oldSelectionHandler(payload);
        }
    };
}());

It's the general way to hook into any handlers for events:
- get a reference to the old handler
- overwrite the old handler
- call the old handler in your new one

Thanks guys, I figured it out:

Code:

#modinfo.json
# ... snip
        "live_game": [
            "coui://ui/mods/mymod.js/live_game.js"
        ]
# ... snip

# ui/mods/mymod/live_game.js
model.selection.subscribe(function (value) {
    console.log('selection made: ', value);
}

The handlers.selection method mentioned here doesn't distinguish between a completed selection (clicking or using a keybindings), versus a selection-in-progress (drawing a bandbox over units, but not letting go of the mouse button yet). But the model.selection.subscribe method does.

Check this thread: Suspected UI bug: Clicking units produces "selectionResult", "Select Idle Fabbers" does not for more information.