Iterable.forEach, Map.forEach, and Stream.forEach are meant to execute some code on each element of a collection for side effects. They take callbacks that have a void return type. Consequently, those .forEach methods cannot use any values returned by the callbacks, including returned Futures. If you supply a function that returns a Future, that Future will … Read more
Looks like you’ve got some answers to this, however I think there is something worth mentioning here that will greatly simplify your code. jQuery introduced the $.when in v1.5. It looks like: $.when($.ajax(…), $.ajax(…)).then(function (resp1, resp2) { //this callback will be fired once all ajax calls have finished. }); Didn’t see it mentioned here, hope … Read more
It is called while the parameters for Button are being assigned: command=Hello() If you want to pass the function (not it’s returned value) you should instead: command=Hello in general function_name is a function object, function_name() is whatever the function returns. See if this helps further: >>> def func(): … return ‘hello’ … >>> type(func) <type … Read more
You used a function call instead of a function reference as the first parameter of the setInterval. Do it like this: function timer() { console.log(“timer!”); } window.setInterval(timer, 1000); Or shorter (but when the function gets bigger also less readable): window.setInterval( function() { console.log(“timer!”); }, 1000)
In many cases, you have an interface and pass along an object that implements it. Dialogs for example have the OnClickListener. Just as a random example: // The callback interface interface MyCallback { void callbackCall(); } // The class that takes the callback class Worker { MyCallback callback; void onEvent() { callback.callbackCall(); } } // … Read more
.complete + callback This is a standards compliant method without extra dependencies, and waits no longer than necessary: var img = document.querySelector(‘img’) function loaded() { alert(‘loaded’) } if (img.complete) { loaded() } else { img.addEventListener(‘load’, loaded) img.addEventListener(‘error’, function() { alert(‘error’) }) } Source: http://www.html5rocks.com/en/tutorials/es6/promises/
This is a simple question but the answer is surprisingly complex. The short answer is you can do what you’re trying to do with std::bind1st or boost::bind. The longer answer is below. The compiler is correct to suggest you use &CLoggersInfra::RedundencyManagerCallBack. First, if RedundencyManagerCallBack is a member function, the function itself doesn’t belong to any … Read more
Just create a function(magic) {} as a wrapper callback: callWithMagic(function(magic) { return processMagic(magic, 42); }); Or using ECMAScript 6: arrow functions: callWithMagic(magic => processMagic(magic, 42));
Yes there is, since setState works in an asynchronous way. That means after calling setState the this.state variable is not immediately changed. so if you want to perform an action immediately after setting state on a state variable and then return a result, a callback will be useful Consider the example below …. changeTitle: function … Read more
Developers are often confused by what a callback is because of the name of the damned thing. A callback function is a function which is: accessible by another function, and is invoked after the first function if that first function completes A nice way of imagining how a callback function works is that it is … Read more