giwebkit: Timer impl feature complete

library/pyjamas/Timer.giwebkit.py

@@ -0,0 +1,57 @@
+class Timer(object):
+
+    def __setTimeout(self, periodMillis, impl='Timeout'):
+        '''
+        Coordinate with JavaScript and realize a new Timer.
+
+        A private communication channel is established by both sides
+        acquiring a ref to the same TextNode; once linked, the node is
+        removed from the DOM tree, but can still recieve all events.
+        It also serves as a nucleus for adding more nodes to the link -- eg.
+        wrapping in <div>[TextNode]</div> -- for whatever reason, and
+        without limit.
+
+        Here we just use the private node to trigger Python callbacks;
+        Python registers listeners and JavaScript synthesizes events.
+        PyGObject is capable of clearing Timers, but is unable to create
+        new ones (upstream bug?).
+        '''
+        # TODO: Timers/Intervals in JS will not queue for safety reasons;
+        #       if we're unable to process the first event before another
+        #       fires, we end up with an unbounded backlog of Timer events.
+        #       For this reason, JS will only queue one event of this type
+        #       at-a-time ... we MUST ensure this same behaviour!
+        code = r'''
+            (function(buf, ms){
+                var wnd = window;
+                var doc = wnd.document;
+                var evt = doc.createEvent('UIEvent');
+                var run = function(){buf.dispatchEvent(evt)};
+                var tid = wnd.set%s(run, ms);
+                doc.head.removeChild(buf);
+                tid = buf.data = Number(tid);
+                evt.initUIEvent('Timer', true, true, wnd, tid);
+            }(document.head.lastChild, %s));
+            ''' % (impl, int(periodMillis))
+        mf = get_main_frame()
+        vw = mf._view
+        doc = mf.getDomDocument()
+        run = lambda *a: self.__fire()
+        buf = doc.createTextNode('')
+        doc.head.appendChild(buf)
+        mf.addEventListener(buf, 'Timer', run)
+        vw.execute_script(code)
+        return int(buf.data)
+
+    def __clearTimeout(self, tid, impl='Timeout'):
+        '''Cancel a running Timer.'''
+        wnd = get_main_frame().getDomWindow()
+        return getattr(wnd, 'clear%s' % impl)(int(tid))
+
+    def __setInterval(self, periodMillis, impl='Interval'):
+        '''Passthru to setTimeout(), but call setInterval().'''
+        return self.__setTimeout(periodMillis, impl=impl)
+
+    def __clearInterval(self, tid, impl='Interval'):
+        '''Passthru to clearTimeout(), but call clearInterval().'''
+        return self.__clearTimeout(tid, impl=impl)