Gets whether events are suspended.
Sets whether events are suspended. If true, the observer will not emit events when values are set.
Adds another emitter. Any events fired by this instance will also be fired on the additional emitter.
The emitter
Destroys the observer instance.
Emits the specified event, executing all registered listeners for that event with the provided arguments. If events are suspended, the emit operation will be ignored.
The name of the event to emit.
Optionalarg0: anyThe first argument to pass to the event listeners.
Optionalarg1: anyThe second argument to pass to the event listeners.
Optionalarg2: anyThe third argument to pass to the event listeners.
Optionalarg3: anyThe fourth argument to pass to the event listeners.
Optionalarg4: anyThe fifth argument to pass to the event listeners.
Optionalarg5: anyThe sixth argument to pass to the event listeners.
Optionalarg6: anyThe seventh argument to pass to the event listeners.
Optionalarg7: anyThe eighth argument to pass to the event listeners.
The current instance for chaining.
// Register an event listener
events.on('testEvent', (arg1, arg2) => {
console.log('Event triggered with arguments:', arg1, arg2);
});
// Emit the event
events.emit('testEvent', 'value1', 'value2');
// Emit the event with more arguments
events.emit('testEvent', 'value1', 'value2', 'value3', 'value4');
Path to the value.
Retrieve the observer object without converting it to JSON.
The value at the specified path.
Query whether the object has the specified property.
Path to the value.
Returns true if the value is present and false otherwise.
Path to the value.
Value to insert.
Optionalind: numberIndex to insert the value at.
If true, the insert event will not be emitted.
State value passed to the set event used to disable remote event emission.
Returns true if the value was successfully inserted and false otherwise.
Optionaltarget: anyThe object to JSONify.
The current state of the object tracked by the observer.
Returns the latest observer instance. This is important when dealing with undo / redo where the observer might have been deleted and/or possibly re-created.
The latest instance of the observer.
Path to the value.
Index of the value to move.
Index to move the value to.
If true, the move event will not be emitted.
State value passed to the set event used to disable remote event emission.
Returns true if the value was successfully moved and false otherwise.
Registers an event listener for the specified event name. If the event is emitted, the callback function is executed with up to 8 arguments.
The name of the event to listen for.
The callback function to be executed when the event is emitted.
An EventHandle object that can be used to unbind the event listener.
Registers a one-time event listener for the specified event name. The callback function is executed the next time the event is emitted, and then automatically unbound.
The name of the event to listen for.
The callback function to be executed once when the event is emitted.
An EventHandle object that can be used to unbind the event listener before it is triggered.
// Register a one-time event listener
events.once('testEvent', (arg1, arg2) => {
console.log('Event triggered once with arguments:', arg1, arg2);
});
// Emit the event
events.emit('testEvent', 'value1', 'value2'); // The callback will be called and then unbound.
// Emit the event again
events.emit('testEvent', 'value1', 'value2'); // The callback will not be called this time.
Path to the value.
Index of the value.
If true, the remove event will not be emitted.
State value passed to the set event used to disable remote event emission.
Returns true if the value was successfully removed and false otherwise.
Path to the value.
Value to remove.
If true, the remove event will not be emitted.
State value passed to the set event used to disable remote event emission.
Returns true if the value was successfully removed and false otherwise.
Path to the property in the object.
Value to set.
If true, the change will not be recorded in history.
State value passed to the set event used to disable remote event emission.
If true, the value will be set even if it is the same as the current value.
Returns true if the value was successfully set and false otherwise.
Unbinds an event listener for the specified event name. If a callback function is provided, only that specific listener is removed. If no callback is provided, all listeners for the event are removed. If no event name is provided, all listeners for all events are removed.
Optionalname: stringThe name of the event to unbind. If not provided, all events are unbound.
Optionalfn: HandleEventThe specific callback function to remove. If not provided, all listeners for the event are removed.
The current instance for chaining.
// Register an event listener
const callback = (arg1, arg2) => {
console.log('Event triggered with arguments:', arg1, arg2);
};
events.on('testEvent', callback);
// Unbind the specific event listener
events.unbind('testEvent', callback);
// Unbind all listeners for a specific event
events.unbind('testEvent');
// Unbind all listeners for all events
events.unbind();
Path to the value.
If true, the change will not be recorded in history.
State value passed to the set event used to disable remote event emission.
Returns true if the value was successfully unset and false otherwise.
The Observer class is used to observe and manage changes to an object. It allows for tracking modifications to nested properties, emitting events on changes, and maintaining state consistency. This is particularly useful in applications where state management and change tracking are critical, such as in data-driven interfaces or collaborative applications.
Example