event-handling

We are implementing drag and drop functionality with Angular 2. I'm using the dragover event just to run the preventDefault() function. So that the drop event works as explained in this question . The dragover method is being handled by the onDragOver function in the component. <div draggable="true" (dragover)="onDragOver($event)"> ... In the component, this function prevents default behavior allowing for the dragged item to be dropped at this target. onDragOver(event) { event.preventDefault(); } This works as expected. The dragover event gets fired every few hundred milliseconds. But, every

I have an application that needs to respond to certain events in the following manner: void someMethodWithinSomeClass() { while (true) { wait for event; if (event == SomeEvent) { doSomething(); continue; } if (event == SomeOtherEvent) { doSomethingElse(); continue; } } } This would be running is some thread. In some other threads, operations would create and fire the Events. How do I get these Events to reach the above method/class? What is the proper strategy or architecture for implementing event handling in C++? The C++ Standard doesn't address events at all. Usually, however, if you need

I'm having a problem getting mouse wheel scrolling to work in the following XAML, which I have simplified for clarity: <ScrollViewer HorizontalScrollBarVisibility="Visible" VerticalScrollBarVisibility="Visible" CanContentScroll="False" > <Grid MouseDown="Editor_MouseDown" MouseUp="Editor_MouseUp" MouseMove="Editor_MouseMove" Focusable="False" > <Grid.Resources> <DataTemplate DataType="{x:Type local:DataFieldModel}" > <Grid Margin="0,2,2,2" > <TextBox Cursor="IBeam" MouseDown="TextBox_MouseDown" MouseUp="TextBox_MouseUp" MouseMove="TextBox_MouseMove" /> </Grid> </DataTemplate> </Grid.Resources>

I am attempting to understand Boost.Asio, with the intention of potentially implementing a signaling system using condition variables in conjunction with Boost.Asio. I have seen the other StackOverflow questions boost asio asynchronously waiting on a condition variable , boost::asio async condition , and boost condition variable issue , but none of these questions/answers have satisfactorily touched on an essential question that I have: Is it true that, and/or is there a fundamental reason why, Boost.Asio is not applicable to, or a natural fit with, condition variables? My thinking is that

Is it possible to capture the task manager end process of a windows application within the same windows application itself? I am using a C# 2.0 win app and I would like to do some database processing (change a flag from 'Y' to 'N' in the DB) when an end process happens. Foredecker No, it is not possible to hook the operating system's decision to end a process. Note, this is not done by task manger, ending a process is the responsibility of the kernel. You will need to do two things here: Connect event handlers to the normal user interface messages that tell a application to exit. Use these

A simple scenario: a custom class that raises an event. I wish to consume this event inside a form and react to it. How do I do that? Code examples, please! Note that the form and custom class are separate classes. public class EventThrower { public delegate void EventHandler(object sender, EventArgs args) ; public event EventHandler ThrowEvent = delegate{}; public void SomethingHappened() { ThrowEvent(this, new EventArgs()); } } public class EventSubscriber { private EventThrower _Thrower; public EventSubscriber() { _Thrower = new EventThrower(); //using lambda expression..could use method

I have an EditText field with a Customer Text Watcher on it. In a piece of code I need to change the value in the EditText which I do using .setText("whatever") . The problem is as soon as I make that change the afterTextChanged method gets called which created an infinite loop. How can I change the text without it triggering afterTextChanged? I need the text in the afterTextChanged method so don't suggest removing the TextWatcher . You could unregister the watcher, and then re-register it. Alternatively, you could set a flag so that your watcher knows when you have just changed the text