Factor out timer and delay management

darcs-hash:20091201115019-e4919-fe83e3d69eb997d0c04064b46117690824fe4daf.gz

1 files changed, 69 insertions, 0 deletions

diff --git a/lib/scripts/delay.js b/lib/scripts/delay.js
new file mode 100644
index 000000000..2ef9f8846
--- /dev/null
+++ b/lib/scripts/delay.js
@@ -0,0 +1,69 @@
+/**
+ * Manage delayed and timed actions
+ *
+ * @license GPL2 (http://www.gnu.org/licenses/gpl.html)
+ * @author  Adrian Lang <lang@cosmocode.de>
+ */
+
+/**
+ * Provide a global callback for window.setTimeout
+ *
+ * To get a timeout for non-global functions, just call
+ * delay.add(func, timeout).
+ */
+var timer = {
+    _cur_id: 0,
+    _handlers: {},
+
+    execDispatch: function (id) {
+        timer._handlers[id]();
+    },
+
+    add: function (func, timeout) {
+        var id = ++timer._cur_id;
+        timer._handlers[id] = func;
+        return window.setTimeout('timer.execDispatch(' + id + ')', timeout);
+    }
+};
+
+/**
+ * Provide a delayed start
+ *
+ * To call a function with a delay, just create a new Delay(func, timeout) and
+ * call that object’s method “start”.
+ */
+function Delay (func, timeout) {
+    this.func = func;
+    if (timeout) {
+        this.timeout = timeout;
+    }
+}
+
+Delay.prototype = {
+    func: null,
+    timeout: 500,
+
+    delTimer: function () {
+        if (this.timer !== null) {
+            window.clearTimeout(this.timer);
+            this.timer = null;
+        }
+    },
+
+    start: function () {
+        this.delTimer();
+        var _this = this;
+        this.timer = timer.add(function () { _this.exec.call(_this); },
+                               this.timeout);
+
+        this._data = {
+            _this: arguments[0],
+            _params: Array.prototype.slice.call(arguments, 2)
+        };
+    },
+
+    exec: function () {
+        this.delTimer();
+        this.func.call(this._data._this, this._data._params);
+    }
+};