event-handling

问题 I have prepared the following React Component (React version 1.5.2): var QuickSearch = React.createClass({ searchHandler: function(){ this.props.parent.props.dataSource.search = this.refs.SearchInput.value; this.props.parent.props.dataSource.setPage(1); this.props.parent.getData(); }, refreshHandler: function(){ this.props.parent.props.dataSource.search = this.refs.SearchInput.value; this.props.parent.getData(); }, myEventHandler: function(evt){ console.log(evt); if(evt.keyCode === 13) { evt

问题 In C#, you do something like this: if (Changed != null) Changed(this, EventArgs.Empty); But what do you do in VB.NET? There is RaiseEvent , but is RaiseEvent Changed(Me, EventArgs.Empty) actually checking that something has subscribed to the event? 回答1: Unlike its C# equivalent, RaiseEvent in VB.NET will not raise an exception if there are no listeners, so it is not strictly necessary to perform the null check first. But if you want to do so anyway, there is a syntax for it. You just need to

问题 I was trying to make LINK FINDER and facing 2 issue Issue 1 (Resolved) :: Unable to get url of redirected page This was resolved REFERNCE LINK by using WinHttp.WinHttpRequest.5.1 Issue 2 (Unsolved) :: unable to use WinHttp.WinHttpRequest.5.1 object EVENTS Or no callback to asynchronous request Synchronous request code Set req = CreateObject("WinHttp.WinHttpRequest.5.1") req.open "GET", url, FALSE req.setRequestHeader "Content-Type", "application/x-www-form-urlencoded" req.send PostData This

问题 I have a view with button and touch-move gesture. When user touches button it becomes selected and keeps receiving touch-move events. I want to deselect the button on touch-move and pass moves to gesture. How to cancel touch receiving on button "elegantly"? 回答1: You need to implement the UIGestureRecognizerDelegate. Specifically this method. Then just build your logic for deciding if the gesture should receive the touch or not. If you return NO then the touch is up for grabs for the button.

问题 I'm having a problem when the Silverlight toolkit's ContextMenu is clicked while it is over a UIElement that has registered a Tap event GestureListener . The context menu click propagates to the underlying element and fires its tap event. For instance, say I have a ListBox and each ListBoxItem within it has registered both a ContextMenu and a Tap GestureListener . Assume that clicking context menu item2 is supposed to take you to Page1.xaml, while tapping on any of ListBox items themselves is

问题 I am using commanding in my viewmodel to handle events. like for example I am handling a button click event like this: XAML <i:Interaction.Triggers> <i:EventTrigger EventName="Click"> <i:InvokeCommandAction Command="{Binding mvvmButtonclick}" /> </i:EventTrigger> </i:Interaction.Triggers> Viewmodel Code public ICommand mvvmButtonclick { get; private set; } Viewmodel Constructor code to wireup the command this.mvvmButtonclick = new ActionCommand(this.ButtonClickedEvent); Actual method in the

问题 I am using commanding in my viewmodel to handle events. like for example I am handling a button click event like this: XAML <i:Interaction.Triggers> <i:EventTrigger EventName="Click"> <i:InvokeCommandAction Command="{Binding mvvmButtonclick}" /> </i:EventTrigger> </i:Interaction.Triggers> Viewmodel Code public ICommand mvvmButtonclick { get; private set; } Viewmodel Constructor code to wireup the command this.mvvmButtonclick = new ActionCommand(this.ButtonClickedEvent); Actual method in the

问题 I've got a pretty big setup form which I'd like to populate with data from a class. so I'm doing a lot of Edt1.text := ASettings.FirstThing; I'd like to avoid Edt1.onchange := nil; Edt1.text := ASettings.FirstThing; Edt1.onchange := edt1Onchange; How do I change the text in a text box and sidestep the onchange event. 回答1: I have used something like changing the OnChange handler, but more often, I use a flag. updatingFromCode := true; Edt1.Text := ASettings.FirstThing; updatingFromCode :=

问题 I have an NSAutoreleasePool thread that is designed to pull information down from a web service, i have the web service code working nicely and i can trigger the thread to start in a view controller without any trouble, in fact its working quite nicely. I want to: move the thread instantiation to the appDelegate - easy! have it run periodically and somehow tell the viewcontrollers under it (5 - 10) if new information is downloaded have the capacity to manually execute the thread outside of

问题 I am working on an old code and I have seen in the code that there are many events added with javascript addEventListener and some added with jQuery.on() on the same element but in the detach method it is used only jQuery.off() to remove them. So I was wondering if this code will work as the guys that wrote it expected (to remove all events from the dom element) or the events added with javascript won't be removed. 回答1: It does not. If you investigate the native removeEventListener api you