I need to get the text changed event of tooltip. But I cant see any event like this.
How can I get this event or events which enable me to get this event?
Any help will be greately appreciated.
İbrahim
You would usually bind the value of your ToolTip to a property of your view model.
However if you really require an event, you would do this:
SomeMethod()
{
...
var descriptor = DependencyPropertyDescriptor.FromProperty(
ToolTipService.ToolTipProperty, typeof (UIElement));
// we're interested in a TextBox called textBox
descriptor.AddValueChanged(textBox, TooltipChanged);
...
textBox.ToolTip = "Hello";
}
private void TooltipChanged(object sender, EventArgs eventArgs)
{
// output's "Hello"
Debug.WriteLine(textBox.ToolTip);
}
Related
I have a WPF Datagrid that is bound to a model.
Inside the model I have a property defined as
public String status
{
get
{
return m_status;
}
set
{
m_status = value;
OnPropertyChanged("status");
}
}
This property informs the grid of changes via OnPropertyChanged.
I also handle the SelectionChanged event to trigger different activities.
SelectionChanged="gridSongs_SelectionChanged"
private void gridSongs_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
Console.WriteLine("gridSongs_SelectionChanged " + sender.ToString());
}
During testing this I have noticed that every time I change the property "status" in code the grid updates automatically (which is what I want) but also fires the SelectionChanged Event as well.
Is there any way I can stop the event from firing when I change the model from code but let it go through when user clicks an item in the grid ?
Maybe I could use a different event for the manual selection of items in the grid ?
thanks a lot in advance.
Is there any way I can stop the event from firing when I change the model from code but let it go through when user clicks an item in the grid?
No, but there is a simple workaround. Add a private bool isLocal variable and set it to true before you make any changes and back to false afterwards:
isLocal = true;
status = "Some Value";
isLocal = false;
Then, in your SelectionChanged handler, check this variable and only react if it is false:
private void gridSongs_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
if (!isLocal ) Console.WriteLine("gridSongs_SelectionChanged " + sender.ToString());
}
I've a text box in that i added a event TextChanged but it doesn't giving me all the data i entered in that text box it neglecting last character but i want all chars what i enter in the text box so how can i do this one please help me.
The TextChanged event gives you all the character:
TextBox currentTextBox = sender as TextBox;
string fullText = CurrentTextBox.Text;
Are you sure your not in like a PreviewKeyDownEvent or any other Preview Events. All of these events neglect the last input
Make an extended TextBox class and handle the KeyUp event to force an update to the text property binding after each key stroke.
public class MyWPFTextBox: TextBox
{
public MyWPFTextBox(): base()
{ KeyUp += new KeyEventHandler(MyWPFTextBox_KeyUp); }
private void MyWPFTextBox_KeyUp(object sender, System.Windows.Input.KeyEventArgs e)
{
BindingExpression BE = GetBindingExpression(TextBox.TextProperty);
if (BE != null)
BE.UpdateSource();
}
}
you should look at the PreviewTextInput event.
you also should take a look at mvvm pattern, binding and UpdateSourceTrigger=PropertyChanged. there you do not need events at all, you get your information via binding.
I'm writing some code to detect toggling of selections in a WindForms ListBox with MultiSelect turned on. Since SelectedIndexChanged only lets me see what is selected after the click, I was looking for a way to detect what was selected before the ListBox was clicked. I implemented the MouseDown event and I can get exactly what I want, but an unfortunate side effect is that I have killed the SelectedIndexChanged event. It will not fire.
Is this known behavior? Are there any thoughts about getting to the selection list before the click?
Thanks.
Edited to include code snippets as requested.
Designer generated events:
this.lbPhysicianClinic.SelectedIndexChanged += new System.EventHandler( this.lbPhysicianClinic_SelectedIndexChanged );
this.lbPhysicianClinic.MouseDown += new System.Windows.Forms.MouseEventHandler( this.lbPhysicianClinic_MouseDown );
Code snippet showing MouseDown event:
private void lbPhysicianClinic_MouseDown( object sender, MouseEventArgs e )
{
List<Clinic_List_ByPhysicianResult> Selected = this.PhysicianGetSelectedClinics( this.lbPhysicianClinic.SelectedIndices );
}
Code snippet showing SelectedIndexChanged event:
private void lbPhysicianClinic_SelectedIndexChanged( object sender, EventArgs e )
{
try
{
if ( this.FormInitComplete && this.RefreshUIComplete )
{
List<Clinic_List_ByPhysicianResult> Selected = this.PhysicianGetSelectedClinics( this.lbPhysicianClinic.SelectedIndices );
Clinic_List_ByPhysicianResult DroppedClinic = new Clinic_List_ByPhysicianResult();
I set a breakpoint in each event and if the MouseDown event is there, the SelectedIndexChanged event never fires. It only fires when the MouseDown event is gone.
Hopefully this clarifies things.
The ListBox changes its selection before it raises the MouseDown or SelectedIndexChanged events.
What you need to do is capture the underlying Win32 message and raise an event yourself. You can subclass ListBox to do this.
class MyListBox : ListBox
{
private const int WM_LBUTTONDOWN = 0x201;
public event EventHandler PreSelect;
protected override void WndProc(ref Message m)
{
switch (m.Msg)
{
case WM_LBUTTONDOWN:
OnPreSelect();
break;
}
base.WndProc(ref m);
}
protected void OnPreSelect()
{
if(null!=PreSelect)
PreSelect(this, new EventArgs());
}
}
You can use the MyListBox class, and add a handler for the PreSelect event like so:
this.lbPhysicianClinic.PreSelect +=
new EventHandler(this.lbPhysicianClinic_PreSelect);
Inside the event handler you can access the selected indices before the listbox has changed them.
I have a form with a ComboBox that provides a dropdownlist. On the comboBox's SelectedIndexChanged event, am running some code, but I don't want that code to run when the form loads. Unfortunately, when I load the form (before I make a selection in the combobox), SelectedIndexChanged of the combobox fires (I think when the combobox is databinding). Is there a way of avoiding such behaviour?
If you want to react only when the user change the selected item in the combo box, then it is better to subscribe to SelectionChangeCommitted.
You can simply unbind the SelectedIndexChanged event, call your fill function and bind the SelectedIndexChanged event again. Unfortunately, this doesn't work with a grid.
For example:
this.cmb.SelectionChanged -= new System.EventHandler(this.cmb_SelectionChanged);
cmb.fill(); //Your function
this.cmb.SelectionChanged += new System.EventHandler(this.cmb_SelectionChanged);
Be sure to set the DataSource property in your onload() function after assigning the ValueMember and Datamember properties.
This will help you to solve your problem!
Why not have a boolean flag that indicates when your Form has finished loading?
In your SelectionChanged event, check if the boolean flag is true. If it is true then handle the event, otherwise ignore it.
VB
RemoveHandler lbxNomes.SelectedIndexChanged, AddressOf lbxNomes_SelectedIndexChanged
lbxNomes.DataSource = dst
Label1.Text = String.Format("Encontrados {0} Sócios nesta pesquisa", dst.Rows.Count)
Label1.Visible = True
AddHandler lbxNomes.SelectedIndexChanged, AddressOf lbxNomes_SelectedIndexChanged
Here is a simple solution that leaves your code almost untouched:
In the SelectedIndexChanged event, check if the myComboBox handle is created using the (IsHandleCreated) method. Another added check is to check if the user is actually focusing your combobox control to change selected index.
private void myComboBox_SelectedIndexChanged(object sender, EventArgs e)
{
if (myComboBox.IsHandleCreated && myComboBox.Focused)
{
// Do something here
}
}
It worked for me in a way with the following code:
private void ddlChapter_SelectionChangeCommitted(object sender, EventArgs e)
{
if (ddlChapter.SelectedValue != null)
{
// Do something here
}
}
So basically, I have a bunch of TextBoxes that the user gets to fill out. I've got a button that I want to keep disabled until all the TextBoxes have had text entered in them. Here is a sample XAML TextBox that I'm using:
<TextBox Name="DelayedRecallScore" TextInput="CheckTextBoxFilled" Width="24" />
And here is the function that I'm trying to trigger:
//Disables the OK button until all score textboxes have content
private void CheckTextBoxFilled(object sender, RoutedEventArgs e)
{
/*
foreach (TextBox scorebox in TextBoxList)
{
if (string.IsNullOrEmpty(scorebox.Text))
{
Ok_Button.IsEnabled = false;
return;
}
}
Ok_Button.IsEnabled = true;
*/
MessageBox.Show("THIS MAKES NO SENSE");
}
The MessageBox is not showing up when TextInput should be getting triggered. As an experiment I tried triggering CheckTextBoxFilled() on PreviewTextInput, and it worked fine then, meaning that for whatever reason, the function just isn't getting called. I also have a validation function that is triggered by PreviewTextInput, which works as it should. At first I thought PreviewTextInput might somehow be interfering with TextInput, so I took PreviewTextInput off the TextBox, but that hasn't managed to fix anything. I'm completely befuddled by why this might happen, so any help would be appreciated.
Your handler for the TextInput event is not fired because the TextBox is handling the event. You could try using the TextChanged event instead, since really you just want to know when characters were added or removed from the TextBox.
InitializeComponent();
textbox.AddHandler(TextBox.TextInputEvent,
new TextCompositionEventHandler(TextBox_TextInput_1),
true);
Use "PreviewTextInput" instead, it will work.
Create a new class derived from TextBox. In the new class override the OnTextInput method. Your OnTextInput method will get called before the TextBox gets it.