event-handling

问题 Is it possible, or more precisely how is it possible to use RX.Net to listen to a number and different variety of (WinForms) controls' .TextChanged/.RowsChanged/.SelectionChanged events and whenever one condition is fullfilled (ControlA.Text isn't empty, ControlB.RowsCount > 0 etc) enable that one DoSomething button. I am asking because currently we have a lengthy if/then statement in each of these events' handlers and maintaining them if the condition changes is, due to duplicate code, quite

问题 when trying to ensure my webpage is using unobtrusive javascript I cant seem to get the onclick event to work in my javascript, it only works as an event in the html tag. here is the code var dow = document.getElementById("dowDiv"); dow.onclick=function () {} any reason that this isnt working for me? as all the answers i can find say this is the way to do it, thanks in advance 回答1: There could be several reasons based on the information provided. Most likely, the event function code is being

问题 In my document, there are two svg images: the preview and the result. The result image is computed based on the preview image; I switch between them by adding/removing class hidden-display , which is further affected by css like this: .hidden-display { display: none; } This seems to be working well. While the result image is being computed, I want to hide the preview image and show only a progress bar; once the result image is loaded, I want it to be displayed and hide the progress bar. Here

问题 Am trying to create a web application which reads an existing xls file(we do not control file creation ) using POI and java. The size of the uploaded file is quite large so the goal is to use event driven excel parsing APIs. I was not able to find any API to access cell colors using the event driven approach. However the uploaded excels have some logic based on the cell colors. Any one has an idea how I can go about it? Thanks! 回答1: You probably want a FormatTrackingHSSFListener - that will

问题 I have a GWTP MyPresenter that registers a handler at onBind(), and it works perfectly. The problem is when I leave the presenter using the BACK arrow on the browser. The onUnbind() is never called (I tried with an breakpoint overriding the method, but is never executed). So that this handler is never unregistered. What is wrong? Thanks. public class MyPresenter extends PresenterWidget<ViewDiagramPresenter.MyView> { [...] @Override protected void onBind() { super.onBind(); registerHandler

问题 I want to validate input on two textboxes on my form if the user clicks the close/"red X" button. I assigned an event handler to the FormClosing property of the Form, but when I click it, the program goes into an infinite loop and then throws the stack overflow exception. Here is my code: private bool _Cancel(object sender, EventArgs e) { if (((this.textboxFirstName.Text != null) && (this.textboxFirstName.Text != string.Empty)) || ((this.textboxLastName.Text != null) && (this.textboxLastName

问题 I have VS2010 professional and Im working with a large code base that Im unfamiliar with. I want to know what code gets executed when a certain event occurs (namely, when I click a specific button). I know this could easily be done with Intellitrace, but that requires an Ultimate subscription (which is outrageously expensive). Is there any other way I can do this? Ideally without installing anything new (even if its free), but thats not a deal breaker. 回答1: You can see what .NET code is

问题 Is there Python equivalent of VB6 DoEvents statement where the handler will temporarily pass to the OS? I found similar code in http://code.activestate.com/recipes/496767-set-process-priority-in-windows/ def setpriority(pid=None,priority=1): """ Set The Priority of a Windows Process. Priority is a value between 0-5 where 2 is normal priority. Default sets the priority of the current python process but can take any valid process ID. """ import win32api,win32process,win32con priorityclasses =

问题 I have a section of code which returns events generated by a slider. I bind the event with self.Bind(wx.EVT_SCROLL,self.OnSlide) . The code which handles the event reads something like: def OnSlide(self,event): widget = event.GetEventObject() This is great but an error gets thrown every time the code is executed. It reads: AttributeError: 'PyEventBinder' object has no attribute 'GetEventObject' I want to be able to see which of the sliders generated the event but the error appears every time

问题 Currently what i do is checking if element exist in page. But my code has alot if conditions because of that. Jquery event listeners doesnt show errow when element doesnt exist. How jquery handles that and what texniques can i use for better design ? var el = document.getElementById('el'); var another_el = document.getElementById('another_el'); if(another_el){ el.addEventListener('click', swapper, false); } if(el){ el.addEventListener('click', swapper, false); } .... ... 回答1: How jquery