The thing is, I have 2 usercontrols, lets call them A and B. They both have MouseRightButtonDown and MouseRightButtonUp events and usercontrol A kinda overlaps B.
Now when I right mouse click on A, the mouse event on B does not fire. When I disable the mouseevents on usercontrol A, the mouseevents on usercontrol B fires.
But how can I get them both to fire simultaneously?
(hope I've explained it clearly)
a bit hacky but this would work, bind the event handler only to the control 1 and call the other event handler like this:
private void textBlock1_MouseRightButtonDown(object sender, MouseButtonEventArgs e)
{
Debug.WriteLine("textBlock1_MouseRightButtonDown");
textBlock2_MouseRightButtonDown(sender, e);
}
private void textBlock2_MouseRightButtonDown(object sender, MouseButtonEventArgs e)
{
Debug.WriteLine("textBlock2_MouseRightButtonDown");
}
personally I would not do this, I would do all my best to re-architect the logic and not have to call the other handler from one of the two controls, but without knowing more what your are doing, impossible to tell...
As we are talking about Silverlight here, I strongly suggest to look on how to work Routed Events, which is a mechanism which actually will help you to avoid event relaunching, as these are events that are traverse Visual Tree of your element, from top to bottom.
Definitely better then relaunching events.
Related
I need help on firing an event within C#
Basically I have a onclick event that fires when you click on a checkbox
void OnClick(object sender, RoutedEventArgs e)
{
...
}
I need help on firing an event within C#
Basically I have a onclick event that fires when you click on a checkbox
void OnClick(object sender, RoutedEventArgs e)
{
...
}
However, I need to fire this event once another event has been fired, so within this new event, is it possible I can fire the above one?
private void DataGridCell_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
switch(dataGrid.Name)
{
case "Customer"
//fire OnCLick Event
break;
}
}
I have tried something like
??? += new MouseEventHandler(OnClick);
But I am not sure if this will actually work.
Yes you can, but only if the event is in your own class. You can't even raise a base class' event. You have a put a method in the base class to raise the event, and then call that.
The code you put there is adding another event handler, not raising an event; you don't need to do that.
If it's a button, use btnDoSomething.PerformClickEvent (winforms)
If the handler is in your code, you can call it without raising the event (commenters assume that this is what you want to do but in reaslity there are many cases where you'd need more than this) btnDoSomething_Click(null, null) - null usually works because handler code rarely cares about the sender or arguments and if you don't reference them, you don't need them.
If you can use #4, you can also refactor as mentioned. Usually not needed. But usually so easy to do you it's worth doing for clarity anyway.
For objects that map from Windows widgets of anysort, check out the SendMessage and PostMessage API calls. Wayyyy beyond the scope of this answer, though. Doesn't apply to non-windows-backed objects (but your sample implies windows).
The child controls of my custom control are obstruction the mouse events in my custom control. I have worked through the accepted answer and the answer at the bottom of this thread...
exposing-events-of-underlying-control
I haven't gotten them to work (the answer at the bottom seemed most straight forward to me). But really I would like to disable the events of them altogether. I have a pictureBox and a label, I don't need to interact with either of the child controls. Is there a way to disable them so they wont interfere with the events of my custom control?
Edit:
I'm using the custom control to gather and process a number of things and make them available as properties. When I click on it, I need to access to the properties. When the event happens at the child control, I don't have access to the propertied of my custom control. The following code is in my form...
public void Form1_MouseDown(object sender, MouseEventArgs e)
{
var myControl = sender as SubstanceViewer;
richTextBox1.Text = myControl.substanceInfo;
}
so I will need to access the properties of the parent control.
If you need the the events that are normally trapped by the child controls to be handled by the custom control itself, then simply wire up those events at run-time in the constructor of the custom control.
For example if you needed the MouseMove() event of the PictureBox and Label to fire the already wired up event of the UserControl:
public partial class SomeUserControl : UserControl
{
public SomeUserControl()
{
InitializeComponent();
this.pictureBox1.MouseMove += SomeUserControl_MouseMove;
this.label1.MouseMove += SomeUserControl_MouseMove;
}
private void SomeUserControl_MouseMove(object sender, MouseEventArgs e)
{
}
}
Be aware, though, that since different controls are firing the same handler you'll need to take that into account. For example, the e.X and e.Y values in the handler above would be relative to the source control.
*You can also wire these events up at design-time using the IDE itself, but I thought code better illustrated the solution.
I am trying to use the MouseClick event from the properties of a listView to handle left and right mouse clicks.
Unfortunately the event never seems to fire. (Double clicked on the event to create a property, entered a bit of simple code and placed a breakpoint on the first line). The same is true of several other events listed in the properties (ItemSelectionChanged seems to work but the other events I have tried don't fire.
Here is the code added:
In form.designer.cs:
this.listView1.MouseClick += new System.Windows.Forms.MouseEventHandler(this.listView1_MouseClick);
In form.cs:
private void listView1_MouseClick(object sender, MouseEventArgs e)
{
Some code
}
That method never gets called when I click on the listview. The listview is inside a tab on top of the stack.
I guess I am probably forgetting something very basic but what?
ListView is a bit unusual, its MouseClick event doesn't fire unless you click an item in the view. Workaround is to use the MouseDown or MouseUp event instead. You typically are much more interested in the ItemSelectionChanged event btw. You probably need its HitTest() method to see exactly what was clicked if you use MouseDown/Up.
I have a very simple requirement, i.e. I want to send a synthetic event to a UIElement, in this case, a Grid. What I want is simply that I be able to send a synthetic event to an UIElement.
For example,
StackPanel myPanel;
StackPanel topPanel;
topPanel.MouseLeftButtonUp += new MouseButtonEventHandler(topPanel_MouseLeftButtonUp);
private void topPanel_MouseLeftButtonUp(object sender, MouseEventArgs args) {
// Here I want to send the MouseLeftButtonUp event to myPanel
}
It is possible using RaiseEvent, but it is a protected event and hence I cannot just call it on an instance of any UIElement. So how do I go about sending a synthetic event on existing classes?
P.S: The reason that I cannot create custom inherited classes is that the current code base is too huge and the number of changes that will be required in case I take such an approach are not feasible.
Any help is greatly appreciated.
Regards,
roahn
Instead of raising events, you could just move the relevant code from the event handler to a method. Then, you can just call the method whenever you want to simulate a button click. However, if you want to simulate the button click on an element, you could do this:
//Assuming myPanel_MouseLeftButtonUp is the event handler for myPanel
myPanel_MouseLeftButtonUp(null, null);
I tried this XAML:
<Slider Width="250" Height="25" Minimum="0" Maximum="1" MouseLeftButtonDown="slider_MouseLeftButtonDown" MouseLeftButtonUp="slider_MouseLeftButtonUp" />
And this C#:
private void slider_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
sliderMouseDown = true;
}
private void slider_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
sliderMouseDown = false;
}
The sliderMouseDown variable never changes because the MouseLeftButtonDown and MouseLeftButtonUp events are never raised. How can I get this code to work when a user has the left mouse button down on a slider to have a bool value set to true, and when the mouse is up, the bool is set to false?
Sliders swallow the MouseDown Events (similar to the button).
You can register for the PreviewMouseDown and PreviewMouseUp events which get fired before the slider has a chance to handle them.
Another way to do it (and possibly better depending on your scenario) is to register an event handler in procedural code like the following:
this.AddHandler
(
Slider.MouseLeftButtonDownEvent,
new MouseButtonEventHandler(slider_MouseLeftButtonDown),
true
);
Please note the true argument. It basically says that you want to receive that event even if it has been marked as handled. Unfortunately, hooking up an event handler like this can only be done from procedural code and not from xaml.
In other words, with this method, you can register an event handler for the normal event (which bubbles) instead of the preview event which tunnels (and therefore occur at different times).
See the Digging Deeper sidebar on page 70 of WPF Unleashed for more info.
Try using LostMouseCapture and GotMouseCapture.
private void sliderr_LostMouseCapture(object sender, MouseEventArgs e)
private void slider_GotMouseCapture(object sender, MouseEventArgs e)
GotMouseCapture fires when the user begins dragging the slider, and LostMouseCapture when he releases it.
I'd like to mention that the Slider doesn't quite swallow the entire MouseDown event. By clicking on a tick mark, you can get notified for the event. The Slider won't handle MouseDown events unless they come from the slider's... slider.
Basically if you decide to use the
AddHandler(Slider.MouseLeftButtonDownEvent, ..., true)
version with the ticks turned on, be sure that the event was handled previously. If you don't you'll end up with an edge case where you thought the slider was clicked, but it was really a tick. Registering for the Preview event is even worse - you'll pick up the event anywhere, even on the white-space between ticks.