DataGridColumnHeader has event MouseLeftButtonDown. How can i use this event ?
How can i join DataGridColumnHeader with DataGridColumn ?
for Example:
...
DataGridTextColumn TC;
TC = new DataGridTextColumn();
TC.Header = "ID";
TC.Binding = new Binding();
TC.Binding.Converter = new MyCustomConverter();
TC.Binding.ConverterParameter = 0;
// I need something like this:
TC.MouseLeftButtonDown += new event ....
// i need - when click on column header, my custom function will executed.
dataGrid.Columns.Add( TC );
worst code i have ever seen;) sry
u should use a method(callback)/lambda sure satisfies an event delegate signature to handle the event
Callback approach:
TC.MouseLeftButtonDown += MouseLeftButtonDownHandler;
//define callback
private void MouseLeftButtonDownHandler(object sender, MouseButtonEventArgs mouseButtonEventArgs)
{
//write ur logic here...
}
Lambda approach
TC.MouseLeftButtonDown += (sender, args) => {//write ur logic here}
//where "sender" means the object raises the event(i.e. "TC"), args - object contains some helpfull information about the happened event(like "ClickCount", etc.).
This links will be usefull:
Delegates
Events
Related
How can i get data from devexress gridcontrol's detail row via double-click.
If i focused on child row gridview's double click event doesn't catch.
i tried this method, but my request is catching data by double click
private void gcOperasyonlar_FocusedViewChanged(object sender, DevExpress.XtraGrid.ViewFocusEventArgs e)
{
if (e.View != null && e.View.IsDetailView)
(e.View.ParentView as GridView).FocusedRowHandle = e.View.SourceRowHandle;
GridView detailView = gcOperasyonlar.FocusedView as GridView;
MessageBox.Show(detailView.GetFocusedRowCellValue("Kalip").ToString());
}
thanks for your help
There is also an easier way:
ColumnView cv = _gridControlxyz.FocusedView as ColumnView;
selectedRow row = cv.GetRow(cv.FocusedRowHandle)
I found this code on the forum, It might be useful as long as your grid is not editable (so that mouse click doesn't activate the editable field).
private void gridView1_DoubleClick(object sender, EventArgs e) {
GridView view = (GridView)sender;
Point pt = view.GridControl.PointToClient(Control.MousePosition);
DoRowDoubleClick(view, pt);
}
private static void DoRowDoubleClick(GridView view, Point pt) {
GridHitInfo info = view.CalcHitInfo(pt);
if(info.InRow || info.InRowCell) {
string colCaption = info.Column == null ? "N/A" : info.Column.GetCaption();
MessageBox.Show(string.Format("DoubleClick on row: {0}, column: {1}.", info.RowHandle, colCaption));
}
}
http://www.devexpress.com/Support/Center/Question/Details/A2934
Let's say you have two gridviews (I'm guessing you're using gridviews in your grid control): gvMaster and gvDetail.
You should implement event DoubleClick for your gvDetail in order to achieve desired functionality:
private void gvDetail_DoubleClick(object sender, EventArgs e) {
var gv = sender as GridView; // sender is not gvDetail! It's an instance of it. You have as many as there are rows in gvMaster
var row = gv.GetDataRow(e.FocusedRowHandle); // or use gv.GetRow(e.FocusedRowHandle) if your datasource isn't DataSet/DataTable (anything with DataRows in it)
MessageBox.Show(row["Kalip"].ToString());
}
I have a parameterised constructor in My Application. I want to add controls dynamically to my silverlight Child Control Page. But it gives NullReferenceException.
I can't find out why it returns null.Can any help me with this situation?
public PDFExport(FrameworkElement graphTile1, FrameworkElement graphTile2,FrameworkElement graphTile3)
{
Button btnGraph1 = new Button();
string Name = graphTile1.Name;
btnGraph1.Content = Name;
btnGraph1.Width = Name.Length;
btnGraph1.Height = 25;
btnGraph1.Click += new RoutedEventHandler(btnGraph1_Click);
objStack.Children.Add(btnGraph1);
LayoutRoot.Children.Add(objStack); // Here am getting null Reference Exception
_graphTile1 = graphTile1;
_graphTile2 = graphTile2;
_graphTile3 = graphTile3;
}
Thanks.
I guess objStack is a stackpanel declared in your XAML?
Be aware that the UI component of your xaml are build by the call to InitializeComponent.
Thus objStack will not exist until you call InitializeCOmponent() in your constructor.
Also, you should know that the call to InitializeComponent is asynchronous, so you code should look like something like that:
private readonly FrameworkElement _graphTile1;
private readonly FrameworkElement _graphTile2;
private readonly FrameworkElement _graphTile3;
public PDFExport(FrameworkElement graphTile1, FrameworkElement graphTile2, FrameworkElement graphTile3)
{
_graphTile1 = graphTile1;
_graphTile2 = graphTile2;
_graphTile3 = graphTile3;
}
private void PDFExport_OnLoaded(object sender, RoutedEventArgs e)
{
Button btnGraph1 = new Button();
string Name = _graphTile1.Name;
btnGraph1.Content = Name;
btnGraph1.Width = Name.Length;
btnGraph1.Height = 25;
btnGraph1.Click += new RoutedEventHandler(btnGraph1_Click);
objStack.Children.Add(btnGraph1);
LayoutRoot.Children.Add(objStack);
}
Hope it helps.
As per my research i got that, why it raises an exception: Because there is no
InitializeComponent() in My Constructor and am not calling parent constructor.
That is the reason it raises Exception.
Just Add InitializeComponent() to the code, simple
I have a DataGrid showing some databases having quite some columns.
I would like that, when the user edit a new row, some values are set automatically.
With the windows form DataGrid that would be easy, since there's RowsAdded event handler.
But how could i handle this with the wpf DataGrid ??
Edit : my DataGrid is bound in Xaml to a public property which is an ITable. When user select a table in a ComboBox, the property is updated with corresponding table.
Yes there's autogenerating column, and the way the user can enter a new row is to edit the last blank row (default behaviour).
You can do this in the LoadingRow event. Try something like this:
private void myDataGrid_LoadingRow(object sender, System.Windows.Controls.DataGridRowEventArgs e)
{
MyObject myObject = e.Row.Item as MyObject;
if (myObject != null)
{
myObject.PropertyOne = "test";
myObject.PropertyTwo = 2;
}
}
Ok i think i got it.
When a DataTable is bound to a DataGrid, a CollectionView is created in order to see it. You can get it by using the (static/shared) CollectionView.GetDefaultView(ThePropertyThatIsBound) method.
Since it implements ICollectionChanged, you can add an event handler to the CollectionChangedEvent.
In the CollectionChanged event handler, if you have a new item (e.NewItems.Count>0) you must check it against System.Windows.Data.CollectionView.NewItemPlaceholder and if it is not a place holder, then it is a brand new item, for wich i can set all default values.
Assign a CollectionViewSource to your DataGrid then listen to the CollectionChanged event as following :
..
public CollectionViewSource ViewSource { get; set; }
..
this.ViewSource = new CollectionViewSource();
this.ViewSource.Source = new List<YourObjectType>();
this.ViewSource.View.CollectionChanged += View_CollectionChanged;
..
private void View_CollectionChanged(object sender,System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
{
if (e.NewItems.Count > 0)
{
YourObjectType myObject = e.NewItems[e.NewItems.Count-1] as YourObjectType;
if (myObject != null)
{
myObject.Property = TheValueYouWant;
..
}
}
}
..
<DataGrid ItemsSource="{Binding ViewSource.View}" ../>
I have a GridView and I want when I change a cell to see if its new value is valid by mine function ValidateValue(string aValue) and if it is valid - to store the new value and old value as a pair in Struct S {string old,new}; How to do this?
Handle the GridView's ValidatingCell event for this purpose. Here is some sample code showing how to obtain new and old edit values:
private void gridView1_ValidatingEditor(object sender, DevExpress.XtraEditors.Controls.BaseContainerValidateEditorEventArgs e) {
BaseEdit edit = (sender as GridView).ActiveEditor;
object oldValue = edit.OldEditValue;
object newValue = e.Value;
}
Is there any way to sanely instantiate WPF objects in LinqPad? Here's my example (the correct assemblies are added in the query, etc):
var w = new Window();
w.Loaded += (o,e) => {
w.Content = new TextBlock() { Text = "Foo" };
};
w.Show();
However, this dies a horrible death:
System.Runtime.InteropServices.InvalidComObjectException: COM object that has been separated from its underlying RCW cannot be used.
at System.Windows.Input.TextServicesContext.StopTransitoryExtension()
at System.Windows.Input.TextServicesContext.Uninitialize(Boolean appDomainShutdown)
at System.Windows.Input.TextServicesContext.TextServicesContextShutDownListener.OnShutDown(Object target, Object sender, EventArgs e)
at MS.Internal.ShutDownListener.HandleShutDown(Object sender, EventArgs e)
Any clues on how I can get this to work?
Another way to do it is as follows:
w.ShowDialog();
Dispatcher.CurrentDispatcher.InvokeShutdown(); // Cleanly end WPF session.
More examples:
new Window { Content = "Foo" }.ShowDialog();
new Window { Content = new Button { FontSize = 50, Content = "Foo" } }.ShowDialog();
Dispatcher.CurrentDispatcher.InvokeShutdown(); // Cleanly end WPF session.
You need to run a message loop by calling new Application().Run(w).