In a datagridview with rowheaders visibility set to false and allowusertoresizerow set to true, i need to prevent the celldoubleclick event to trigger if doubleclicked on the rowdivider (Toublearrow of the row resize is visible when the cursor is on the divider).
Thanks
I guess the easiest way would be checking the clicked area of the grid on the CellDoubleClick event itself; the logic would be to return in case rowresizetop or rowresizebottom areas are clicked and continue processing if not. Please check an example below for more details:
private void dataGridView1_CellDoubleClick(object sender, DataGridViewCellEventArgs e)
{
// get mouse coordinates
Point mousePoint = dataGridView1.PointToClient(Cursor.Position);
DataGridView.HitTestInfo hitTestInfo = dataGridView1.HitTest(mousePoint.X, mousePoint.Y);
// need to use reflection here to get access to the typeInternal field value which is declared as internal
FieldInfo fieldInfo = hitTestInfo.GetType().GetField("typeInternal",
BindingFlags.Instance | BindingFlags.NonPublic);
string value = fieldInfo.GetValue(hitTestInfo).ToString();
if (value.Equals("RowResizeTop") || value.Equals("RowResizeBottom"))
{
// one of resize areas is double clicked; stop processing here
return;
}
else
{
// continue normal processing of the cell double click event
}
}
hope this helps, regards
Related
I have a combobox that is created with data from a dataset
foreach(var item in ds.MiDESValues)
{
string comboboxtext = ds.MiDESValues.Rows[k][1].ToString();
sFactorCB.Items.Add(comboboxtext);
k++;
}
On a selectionchanged event it will populate a listbox with that selection
private void sFactors_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
string add = sFactorCB.SelectedValue.ToString();
var svalue = ds.MiDESValues.Rows[0][2].ToString();
int Svalue = int.Parse(svalue);
SValue.Add(svalue);
SelectionListBox.Items.Add(add);
SelectionBox.Add(add);
// when a new item is added to Selection list box, select it and show it
// this will keep the last item highlighted and as the list grows beyond
// the view of the list box, the last item will always be shown
SelectionListBox.SelectedIndex = SelectionListBox.Items.Count - 1;
SelectionListBox.ScrollIntoView(SelectionListBox.SelectedItem);
}
That list box then used to populate a listbox used on the next page. If I navigate to the next page and then navigate back, the combobox is still showing the last selection I made therefor the listbox is being populated with that value.
I have tried setting the selectedindex of the combobox to sFactorCB.SelectedIndex = -1;, at the end of the sFactors_SelectionChanged event but i get System.NullReferenceException. How can I get the combobox to reset back to a non-selected item state? Thanks
Actually, you are doing it correctly. To clear the selection either set the SelectedIndex to -1 or the SelectedItem to null.
The problem is that once you do that your sFactors_SelectionChanged gets called again and since there is no current selection, the SelectedValue property is null thus causing the following to fail:
string add = sFactorCB.SelectedValue.ToString();
How to solve this sort of depends on your intended results when nothing is selected. The simplest thing to do would be to just check for nothing selected at the start of the handler and simply return.
private void sFactors_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
if (sFactorCB.SelectedIndex == -1 || sFactorCB.SelectedValue == null)
return;
string add = sFactorCB.SelectedValue.ToString();
...
In order to select multiple checkbox within Wrap panel using Shift Key.
Capturing the Mouse down event position on Shift Keydown, on second mouse down with shift keydown, getting the 2 positions of the selection, then Need to Select the checkbox control with in the selected area.
How do I find the controls within 2 positions (System.Window.Point) or System.Windows.rect. The following code is selecting all of the checkbox within the wrappanel(lesscolorpanel).
private System.Windows.Point startPoint;
System.Windows.Point checkpPoint;
private System.Windows.Point PointWhereMouseIs;
private void LessColourPanel_OnPreviewMouseDown(object sender, MouseButtonEventArgs e)
{
if (Keyboard.IsKeyDown(Key.LeftShift) || Keyboard.IsKeyDown(Key.RightShift))
{
if (startPoint == checkpPoint)
{
//GET THE MOUSE POSITION
startPoint = Mouse.GetPosition(lessColourPanel);
PointWhereMouseIs = checkpPoint;
}
else if(PointWhereMouseIs==checkpPoint)
{
//CAPTURE END MOUSE POSITION
PointWhereMouseIs = Mouse.GetPosition(lessColourPanel);
//FIND CONTROLS WIHIN RECTANGLE
Rect selareaRect = new Rect(startPoint, PointWhereMouseIs);
foreach (System.Windows.Controls.CheckBox chkitemBox in FindVisualChildren<System.Windows.Controls.CheckBox>(lessColourPanel))
{
var rectBounds = VisualTreeHelper.GetDescendantBounds(chkitemBox);
Vector vector = VisualTreeHelper.GetOffset(chkitemBox);
rectBounds.Offset(vector);
if (rectBounds.IntersectsWith(selareaRect))
{
chkitemBox.IsChecked = true;
}
}
startPoint = checkpPoint;
}
}
}
Got it, and for viewers refer Ashley Davis post
The credit goes to Ashley Davis.
I have a XtraGrid with one GridView, with a column with checkbox repository item. Now I am handling the CellValueChanging event because I want to only allow the user to check or uncheck based on calculations on other column values on the same row hence I need the e.RowHandle and e.Column of this event and this cannot be done on the EditValueChanging of the repository control.
Now somewhere my calculations say that user cannot check a particular cell to and I throw a message box and try Me.BandedGridView1.SetRowCellValue(e.RowHandle, e.Column, False) but unfortunately this does not set the value to false of that cell.
I need to do it here and here only because of the huge number of calculations based on other column values and I need to set value of the current cell whose event I'm handling right.
Please help.
I'm using DevExpress 9.2 (no chance of upgrading to higher version)
Try this code it's working perfectly !
private void GridView1_CellValueChanged(object sender, CellValueChangedEventArgs e)
{
if (e.Column.Caption != "yourColumnCaption") return;
GridView1.SetFocusedRowCellValue("yourColumnFieldName", 1);
}
You might want to prevent updates by handling ShowingEditor event.
class TestData
{
public TestData(string caption, bool check)
{
Caption = caption;
Check = check;
}
public string Caption { get; set; }
public bool Check { get; set; }
}
Initialize some test data:
BindingList<TestData> gridDataList = new BindingList<TestData>();
gridDataList.Add(new TestData("First row", true));
gridDataList.Add(new TestData("Second row", true));
gridControl.DataSource = gridDataList;
Handle ShowingEditor. Check if user is allowed to change chechbox. If not, cancel the event.
private void gridView1_ShowingEditor(object sender, CancelEventArgs e)
{
GridView view = sender as GridView;
// Decision to allow edit using view.FocusedRowHandle and view.FocusedColumn
if (view.FocusedColumn.FieldName == "Check")
{
// Allow edit of odd rows only
bool allowEdit = view.FocusedRowHandle % 2 == 1;
e.Cancel = !allowEdit;
}
}
I have a WPF Datagrid and I'm implementing drag and drop functionality.
The datagrid has a list of "files" and the user can drag them and copy the file to the desktop.
This is done like this:
string[] files = new String[myDataGrid.SelectedItems.Count];
int ix = 0;
foreach (object nextSel in myDataGrid.SelectedItems)
{
files[ix] = ((Song)nextSel).FileLocation;
++ix;
}
string dataFormat = DataFormats.FileDrop;
DataObject dataObject = new DataObject(dataFormat, files);
DragDrop.DoDragDrop(this.myDataGrid, dataObject, DragDropEffects.Copy);
I have two questions:
1. When I want to drag multiple items- this is a problem because after I select a couple and start clicking on one to start dragging- only that gets selected and the other items get deselected. I tried the solution that is given here but for some reason it doesn't work.
2. I want to remove the dragged item from the datagrid after it is copied. The problem is that I don't know how to check if the file was copied or whether the user just dragged it on the screen without copying it.
I hope you can help me solve these problems.
Thanks!
I think this i what you are looking for:
add this code to the DataGrid__PreviewMouseLeftButtonDown event handler:
private void DataGrid_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
this.startingPosition = e.GetPosition(null);
DependencyObject dep = (DependencyObject)e.OriginalSource;
// iteratively traverse the visual tree until get a row or null
while ((dep != null) && !(dep is DataGridRow))
{
dep = VisualTreeHelper.GetParent(dep);
}
//if this is a row (item)
if (dep is DataGridRow)
{
//if the pointed item is already selected do not reselect it, so the previous multi-selection will remain
if (songListDB.SelectedItems.Contains((dep as DataGridRow).Item))
{
// now the drag will drag all selected files
e.Handled = true;
}
}
}
and now the draging won't change you selection.
Have a good luck!
I used that article to write my answer
Improved on finding the row.
Also selecting the clicked row when not dragging is added.
This now behaves exactly as other Microsoft selectors (eg Outlook)
public TreeDataGrid()
{
Loaded += TreeDataGrid_Loaded;
LoadingRow += new EventHandler<DataGridRowEventArgs>(TreeDataGrid_LoadingRow);
}
#region MultiSelect Drag
object toSelectItemOnMouseLeftButtonUp;
void TreeDataGrid_LoadingRow(object sender, DataGridRowEventArgs e)
{
e.Row.PreviewMouseLeftButtonDown += new MouseButtonEventHandler(Row_PreviewMouseLeftButtonDown);
e.Row.PreviewMouseLeftButtonUp += new MouseButtonEventHandler(Row_PreviewMouseLeftButtonUp);
}
void Row_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
DataGridRow row = (DataGridRow)sender;
toSelectItemOnMouseLeftButtonUp = null; // always clear selecteditem
if (SelectedItems.Contains(row.Item)) //if the pointed item is already selected do not reselect it, so the previous multi-selection will remain
{
e.Handled = true; // this prevents the multiselection from disappearing, BUT datagridcell still gets the event and sets DataGrid's private member _selectionAnchor
toSelectItemOnMouseLeftButtonUp = row.Item; // store our item to select on MouseLeftButtonUp
}
}
void Row_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
DataGridRow row = (DataGridRow)sender;
if (row.Item == toSelectItemOnMouseLeftButtonUp) // check if it's set and concerning the same row
{
if (SelectedItem == toSelectItemOnMouseLeftButtonUp) SelectedItem = null; // if the item is already selected whe need to trigger a change
SelectedItem = toSelectItemOnMouseLeftButtonUp; // this will clear the multi selection, and only select the item we pressed down on
typeof(DataGrid).GetField("_selectionAnchor", BindingFlags.Instance | BindingFlags.NonPublic).SetValue(this, new DataGridCellInfo(row.Item, ColumnFromDisplayIndex(0))); // we need to set this anchor for when we select by pressing shift key
toSelectItemOnMouseLeftButtonUp = null; // handled
}
}
#endregion
I desperately try to figure how to change the background color of a single cell in a winforms dataGridView. I have two columns: if i change content in the second column, i want the cell in the first column of this row to change the background accordingly.
private void dataGridView1_CellPainting(object sender, DataGridViewCellPaintingEventArgs e)
{
if (e.ColumnIndex != 0 || e.RowIndex == -1)
return;
if (dataGridView1.Rows[e.RowIndex].Cells[1].Value.ToString() == "Red")
e.CellStyle.BackColor = Color.Red;
else
e.CellStyle.BackColor = Color.White;
}
private void dataGridView1_CellValueChanged(object sender, DataGridViewCellEventArgs e)
{
if (e.ColumnIndex != 1 || e.RowIndex == -1)
return;
// dataGridView1.Rows[e.RowIndex].Cells[0]. ???
}
The first event handler sets the backColor of the cells in the first column if they are painted. The second event handler should tell the first cell to paint if the value is changed. If i change the columns width it paints the correct color, so the first handler does the work. But how to trigger the cell painting?
Thanx for help.
I would have thought that the edit would have triggered a repaint, but if that event isn't being run after the edit then you should be able to force the issue with something like:
dataGridView1.InvalidateCell(e.RowIndex, 1);
OK, here is the bad hack:
If i insert
var x = dataGridView1.Columns[0].DefaultCellStyle;
dataGridView1.Columns[0].DefaultCellStyle = null;
dataGridView1.Columns[0].DefaultCellStyle = x;
in the CellValueChanged event handler, the whole first column is repainted. So my cell is repainted as well. But that't dirty, isnt't it?
You have to create a new cell style object, set it to the color you want and then apply it to the current cell.
private DataGridViewCellStyle CellStyleGreenBackgnd;
CellStyleGreenBackgnd.BackColor = Color.LightGreen;
dataGridView.CurrentCell.Style.ApplyStyle(CellStyleGreenBackgnd);
Try this.
dataGridView1.Rows[indexhere].Cells[indexhere].Style.ForeColor = Color.Yellow;