WaitCallbacks

Utility to create and wait for multiple callbacks and call a final one after every other callback has been called.

This class is useful for coordinating multiple asynchronous operations, ensuring that a completion handler is called only after all individual operations have finished. Each callback can only be called once.

Common use cases:

• Loading multiple assets in parallel
• Waiting for multiple animations to complete
• Coordinating multiple async operations before proceeding

Example usage:

var wait = new WaitCallbacks(() -> {
    trace("All operations completed!");
});

// Register callbacks for async operations
var cb1 = wait.callback();
var cb2 = wait.callback();
var cb3 = wait.callback();

// Start async operations
loadAsset("image1.png", cb1);
loadAsset("image2.png", cb2);
loadAsset("sound.ogg", cb3);

// The completion callback will fire after all three callbacks are invoked

Note: Once all callbacks have been called and the completion handler has fired, no new callbacks can be registered.

Instance Members #

Get the number of callbacks still pending. This decreases as callbacks are invoked.

Check if all callbacks have completed. Once true, no new callbacks can be registered.

Create a new callback to wait for. Returns a function that should be called when this particular task is done.

The returned callback:

• Can only be called once (subsequent calls are ignored)
• Decrements the pending counter when called
• Triggers the completion callback when it's the last pending callback

Create a new WaitCallbacks instance.

Private Members #