Core/BeforeEvent

Adds a callback/hook to be fired before an action is taken. If that callback returns false, the action should not be taken.

The following example binds a callback function and passes the scope from the view component to use in that callback:

model.before('save', this.doSomethingBeforeSave, this);

Multiple space-separated event names can be bound to a single callback:

view.before('save dispose', this.callback, this);

This method also supports an event map syntax, as an alternative to positional arguments:

this.before({
    render: this.doSomethingBeforeRender,
    dispose: this.doSomethingBeforeDispose,
});

Removes a previously-bound callback function from a before event.

If no context is given, all of the versions of the callback with different contexts will be removed:

this.offBefore('render', this.onRenderBefore);

If no callback is given, all callbacks for the before event will be removed:

this.offBefore('render');

If no event is specified, all callbacks for all before events will be removed from the object:

this.offBefore();

Triggers the before callback for the given event name or list of events.

The following example triggers the callback bound to the before save event given:

this.triggerBefore('save');

Multiple events can be triggered as well:

this.triggerBefore('save render dispose');

Custom arguments (e.g. a, b, c) can be passed to the callback:

this.triggerBefore('save', a, b, c);