In Silverlight 4, I wish to invoke one of the mouse button click events when the right mouse button is clicked. I have the RightMouseButtonDown click event wired up, but I don't know how to manually fire the MouseLeftButtonUp event.
I have tried raising the event in the following fashion.
private void MainLayoutRootMouseButton(object sender, MouseButtonEventArgs e)
{
MouseLeftButtonDown(sender, e);
}
However, a compiler error occurs:
"The event 'System.Windows.UIElement.MouseLeftButtonDown' can only appear on the left hand side of += or -=
What do I need to do to manually raise this event?
The other answers are correct in that they show you how to call those same code paths as you have for the other mouse events.
It should be clear that in Silverlight, you cannot raise (or automate) actual mouse button clicks, for security reasons.
Only user initiated actions such as the actual mouse moving can create real MouseEventArgs and fire the handlers directly, through the Silverlight input system.
You really shouldn't be raising the event itself. Instead, make the code inside the MouseLeftButtonUp its own function and then call that function from both the MouseLeftButtonUp and MouseRightButtonUp events.
e.g.
private void MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
DoTheSameThing(sender, e);
}
private void MouseRightButtonDown(object sender, MouseButtonEventArgs e)
{
DoTheSameThing(sender, e);
}
private void DoTheSameThing(object sender, MouseButtonEventArgs e)
{
//Handle left or right mouse buttons up event
}
In your page's init function you need to have this line of code
someObjectOnPage.MouseLeftButtonDown += new MouseDownEventHandler(DoSomething);
someObjectOnPage.MouseRightButtonDown += new MouseDownEventHandler(DoSomething);
This is pure psuedo code but should lead you on the right track
also your method will need to look like this
void DoSomething(object sender, MouseButtonEventArgs e) { }
Related
I have a TextBox and I want all the text inside of it to be highlighted when the user clicks on it (so that they can replace it easily). I have the following event handler linked up the the TextBox:
private void TextBox_Enter(object sender, EventArgs e) {
SelectAll();
}
When I click on the TextBox, the text is only selected for a fraction of a second (sometime it's so fast I can't see it at all) and then it goes back to being a cursor. Does anyone know how to fix this or if there are any relatively simple workarounds?
I tried the same thing with the TextBox.MouseClick event (and it highlighted the text), but because it was the MouseClick event the text was highlighted every time I clicked the TextBox (even when the TextBox already had focus).
I have also tried SelectionStart = 0; SelectionLength = Text.Length, but the same thing happens. This leads me be believe the issue has something to do with the event.
I also tried the TextBox.GotFocus event and had the exact same problem.
I am doing this in a Windows Form application.
The reason why you didn't see the text getting selected is that the TextBox is busy when one of those events occurred (e.g., caret positioning). You actually select the text, but then the internal event handlers of the TextBox execute and remove the selection e.g. by setting the caret position.
All you have to do is to wait until the internal event handlers have completed.
You do this by using the Dispatcher. When you invoke the Dispatcher asynchronously the delegate is not immediately executed but enqueued and executed once all previously enqueued actions (like the internal event handlers) are cleared from the dispatcher queue.
So going with the TextBox.GotFocus event in WPF (or the TextBox.Enter in WinForms) and the asynchronous Dispatcher will do the trick:
WPF
private async void SelectAll_OnTextBoxGotFocus(object sender, RoutedEventArgs e)
{
await Application.Current.Dispatcher.InvokeAsync((sender as TextBox).SelectAll);
}
WinForms
private void SelectAll_OnTextBoxEnter(object sender, EventArgs e)
{
var textBox = sender as TextBox;
textBox.BeginInvoke(new Action(textBox.SelectAll));
}
Thankfully I found a solution! It turns out that the Click event is executed before the Enter event, this allowed me to set up a JustGotFocus variable and do the following:
private void myTextBox_Click(object sender, EventArgs e) {
this.JustGotFocus = true;
if (JustGotFocus) {
myTextBox.SelectAll();
}
}
private void myTextBox_Enter(object sender, EventArgs e) {
JustGotFocus = false;
}
If anyone else has this problem hopefully my solution is useful.
I have a winforms app in vs2010 and a panel whose click event I would like to fire programatically. How do I do this? Button has a PerformClick but I cannot find the same in Panel.
Your panel's Click event is going to be attached to an event handler, right?
Then just call that event handler from the button's click event handler:
public void Panel1_Click(object sender, EventArgs e)
{
//Do whatever you need to do
}
public void Button1_Click(object sender, EventArgs e)
{
//Do anything you need to do first
Panel1_Click(Panel1, EventArgs.Empty);
}
The effect will be the same as clicking on the panel.
I am new to WinForms events and I am getting a strange error.Well I write when I start my control:
this.MouseUp += MouseUpMethod;
But the problem is, when I release the mouse button out of my control, the program recognize as I release the mouse over the Control. I am not able to understand this error.
Did ever someone got this error?
It's because, by default, your control captures mouse. Just set Control.Capture to false somewhere in your MouseDown event handler, for example:
void MouseDown(object sender, MouseEventArgs e) {
this.Capture = false;
}
As alternative just check in MouseUp that mouse is still inside your control:
void MouseUp(object sender, MouseEventArgs e) {
if (ClientRectangle.Contains(PointToClient(Cursor.Position))) {
// Your code here
}
}
see, you need to associate event with event handler just after your InitializeComponent()
public Form1()
{
InitializeComponent();
this.button2.MouseUp += new System.Windows.Forms.MouseEventHandler(this.button2_MouseUp);
}
then your event handler should be
private void button2_MouseUp(object sender, MouseEventArgs e)
{
//Do stuff here
}
Assume that I have a WinFoms project. There is just one button (e.g. button1).
The question is: is it possible to trigger the ButtonClicked event via code without really clicking it?
Button controls have a PerformClick() method that you can call.
button1.PerformClick();
The .NET framework uses a pattern where for every event X there is a method protected void OnX(EventArgs e) {} that raises event X. See this Msdn article. To raise an event from outside the declaring class you will have to derive the class and add a public wrapper method. In the case of Button it would look like this:
class MyButton : System.Windows.Forms.Button
{
public void ProgrammaticClick(EventArgs e)
{
base.OnClick(e);
}
}
You can just call the event handler function directly and specify null for the sender and EventArgs.Empty for the arguments.
void ButtonClicked(object sender, EventArgs e)
{
// do stuff
}
// Somewhere else in your code:
button1.Click += new EventHandler(ButtonClicked);
// call the event handler directly:
ButtonClicked(button1, EventArgs.Empty);
Or, rather, you'd move the logic out of the ButtonClicked event into its own function, and then your event handler and the other code you have would in turn call the new function.
void StuffThatHappensOnButtonClick()
{
// do stuff
}
void ButtonClicked(object sender, EventArgs e)
{
StuffThatHappensOnButtonClick();
}
// Somewhere else in your code:
button1.Click += new EventHandler(ButtonClicked);
// Simulate the button click:
StuffThatHappensOnButtonClick();
The latter method has the advantage of letting you separate your business and UI logic. You really should never have any business logic in your control event handlers.
Yes, just call the method the way you would call any other. For example:
private void btnSayHello_Click(object sender, EventArgs e)
{
MessageBox.Show("Hello World!");
}
private void btnTriggerHello_Click(object sender, EventArgs e)
{
btnSayHello_Click(null, null);
}
button1.PerformClick();
But if you have to do something like this maybe it's better to move the code you have under the event on a new method ?
Why don't you just put your event code into a Method. Then have the Event execute the method. This way if you need to execute the same code that the Event rises, you can, but simply just calling the "Method".
void Event_Method()
{
//Put Event code here.
MessageBox.Show("Hello!");
}
void _btnSend_Click(object sender, EventArgs e)
{
Event_Method();
}
void AnotherMethod()
{
Event_Method();
}
Make sense? Now the "Click" event AND anywhere in code you can trigger the same code as the "Click" event.
Don't trigger the event, call the method that the event calls. ;)
In most cases you would not need to do that. Simply wrap your functionality in functions related to a specific purpose (task). You call this function inside your event and anywhere else it's needed.
Overthink your approach.
I recently had this problem where I wanted to programatically click a button that had multiple event handlers assigned to it (think UserControl or derived classes).
For example:
myButton.Click += ButtonClicked1
myButton.Click += ButtonClicked2;
void ButtonClicked1(object sender, EventArgs e)
{
Console.WriteLine("ButtonClicked1");
}
void ButtonClicked2(object sender, EventArgs e)
{
Console.WriteLine("ButtonClicked1");
}
When you click the button, both functions will get called. In the instances where you want to programmatically fire an event handler for a function from a form (for example, when a user presses enter in a Text field then call the InvokeOnClick method passing through the control you. For example
this.InvokeOnClick(myButton, EventArgs.Empty);
Where this is the Form instance you are in.
use a for loop to call the button_click event
private void btnadd_Click(object sender, RoutedEventArgs e)
{
for (int i = 0; i <= 2; i++)
StuffThatHappensOnButtonClick();
}
void StuffThatHappensOnButtonClick()
{
........do stuff
}
we assume at least one time you need click the button
When I put a button on a form in C#, Visual Studio 2005, and have an action triggered by a button event, such as MouseHover or MouseDown, then the event triggers a single call to the function which defines the action despite the fact that I may continue to hover or keep the left button down. In this case I am trying to move a graphical object by rotating or translating it. I don't want to continue to click the mouse in order to get a repeated call to the transforming function, just keep the mouse hovering or hold the button down. What maintains the action until I cease my own action?
Set a flag on MouseEnter and keep doing the action while the flag remains true. Set the flag to false on MouseLeave.
In your case you need to use a combination of the events MouseDown, MouseMove and MouseUp.
Here a small simplified example to start:
private void OnMouseDown(object sender, EventArgs e)
{
//hit test to check if the mouse pointer is on a graphical object
_myHitObject = the_selected_object
}
private void OnMouseMove(object sender, EventArgs e)
{
if(_myHitObject != null)
//do your action relative to the mouse movements.
}
private void OnMouseUp(object sender, EventArgs e)
{
_myHitObject = null;
}
The solution is to use DoEvents() which allows for the MouseLeave event to be noted and the class variable "more" to be changed:
private void MouseEnter_ZoomIn(object sender, EventArgs e)
{
more = true;
while (more == true)
{
c1Chart3D1.ChartArea.View.ViewportScale *= ZoomMultiple;
Application.DoEvents();
}
} // MOUSEENTER_ZOOMIN()
//-------------------------------------
private void MouseLeave_Stop(object sender, EventArgs e)
{
more = false;
}