locked()?callbacks.locked() returns a Boolean: true if lock() has frozen that Callbacks list (since jQuery 1.7). It does not change the list or run handlers.
callbacks.locked() // false before lock
callbacks.lock()
callbacks.locked() // true after
lock() → freeze state (action)
locked() → boolean status (question)| Need | Use |
|---|---|
| Is the list locked? | cbs.locked() |
| Freeze the list | cbs.lock() |
| Is the list disabled? | cbs.disabled() |
| Has it been fired? | cbs.fired() |
locked()Ask before you publish again — after a freeze, new fires are ignored.
add() handlers, and fire() as needed.locked() — expect false before any lock.lock() when the state should stop changing.locked() again — expect true from then on.| Piece | Required? | Role |
|---|---|---|
| Callbacks object | Yes | From $.Callbacks() |
| Arguments | None | locked() takes no parameters |
| Return | — | Boolean — has lock() run? |
function locked(callbacks):
return callbacks.hasBeenLocked
// After lock():
// hasBeenLocked = true
// There is no unlock() — stays true for this objectRead-only lock status — pair with lock() for the action.
| Topic | Detail |
|---|---|
| Syntax | callbacks.locked() |
| Since | jQuery 1.7 |
| Returns | Boolean |
| Changes list? | No — status only |
| Action cousin | lock() |
| Related status | disabled() / fired() |
Fire, lock, and watch locked() flip while later fires stay quiet.
Short, copy-ready snippets. Open DevTools Console, or use Try It Yourself for a live editor.
true After lock()Official style: lock the list, then call locked().
var foo = function (value) {
console.log("foo: " + value);
};
var callbacks = $.Callbacks();
callbacks.add(foo);
callbacks.fire("hello");
// foo: hello
callbacks.lock();
console.log(callbacks.locked()); // truefire so the list is active.true.locked().false Before Any LockA fresh list is not locked until you call lock().
var cbs = $.Callbacks();
cbs.add(function () { /* ... */ });
cbs.fire("x");
console.log(cbs.locked()); // false
cbs.lock();
console.log(cbs.locked()); // truelocked() is false.true.locked() vs disabled()Different flags answer different questions.
var cbs = $.Callbacks("memory");
cbs.add(function (v) { console.log(v); });
cbs.fire("ok");
cbs.lock();
console.log(cbs.locked()); // true
console.log(cbs.disabled()); // false (memory list still usable for late adds)memory list freezes new fire values.true.false — not the same flag.fire()Skip publishing when the list is already locked.
var lines = [];
var cbs = $.Callbacks();
cbs.add(function (msg) { lines.push(msg); });
function publish(msg) {
if (cbs.locked()) {
lines.push("skipped:" + msg);
return;
}
cbs.fire(msg);
}
publish("hello");
cbs.lock();
publish("world");
console.log(lines.join("\n"));
// hello
// skipped:worldlocked() first.Most mix-ups confuse the status check with the freeze action.
locked() does not lockCalling locked() never freezes the list. Use lock() for that.
disabled()Locked and disabled are separate flags. Check the one that matches your teardown path.
Once locked() is true, it stays true. Need a reset? Create a new $.Callbacks().
fire() / fireWith() affect fired(), not locked().
callbacks.locked() has shipped since jQuery 1.7 with $.Callbacks. It works in all modern browsers with jQuery loaded.
Return true if lock() has frozen the Callbacks list.
Bottom line: Call locked() to read status. Call lock() when you want to freeze the list.
| Approach | Cost | Best for |
|---|---|---|
locked() | O(1) | Status guards |
lock() then check | O(1) | Finalize + assert |
| Own boolean flag | O(1) | Only if you avoid Callbacks |
Prefer locked() over a parallel custom flag when you already use $.Callbacks — one source of truth.
lock() run?true.One line: locked() asks “did lock() already freeze this list?”
Create Callbacks lists with flags like once, memory, and unique.
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