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Winform DataGRidView Scroll Bar not showing until needed [duplicate]

I have a winform in vs2008 that contains a DataGridView. The datagrid contains a list with several columns. These are fixed width, exept one that I have set up to take whatever space is left and fill the width of the view. The winform is resizeable in all directions.
The issue I am trying to solve is that when I increase the vertical size of the window the scrollbar disappears and the columns snap to the right to fill the extra space. What I would like to happen is that the vertical scrollBar never disappears. Setting ScrollBars to vertical in the properties of the DataGridView does not do this.
Is this at all possible to achieve? And, if so, how do I get the vertical scrollbar to always be visible?

Try subclassing the DataGridView and handling the VerticalScrollBar's VisibleChanged event. You should be able to set the Visible property to True in there, overriding the default behaviour.
Something like this, I think...
public class SubclassedDataGridView : DataGridView
{
public SubclassedDataGridView (): base()
{
VerticalScrollBar.VisibleChanged += new EventHandler(VerticalScrollBar_VisibleChanged);
}
void VerticalScrollBar_VisibleChanged(object sender, EventArgs e)
{
VerticalScrollBar.Visible = true;
}
}

In my case, (re)sorting the grid helped. Try sth like this:
if (gridName.SortedColumn == null)
gridName.Sort(gridNameColumns[columnName],ListSortDirection.Ascending);
else
{
ListSortDirection dir;
if (gridName.SortOrder == SortOrder.Descending)
dir = ListSortDirection.Descending;
else dir = ListSortDirection.Ascending;
gridName.Sort(gridName.SortedColumn, dir);
}

One of the possibility is to trigger the event of when the scrollbar is disapearing so you can prevent the event and stop it.

WPF- Horizontal and Vertical position of a Run Element in a FlowDocument

Is there anyway to get the horizontal position(pixel) and vertical position(pixel) of a Run element in a FlowDocument?
Edit:
All i need to do is scroll to that position and make it the top line of the FlowDocument.

To Answer Your Question
The code needed to get the position of a content element in a document is all internal to .NET and not publically exposed. You would need access to an IContentHost implementation, which the built-in document viewers do not publically expose. So, there is no supported way to do what you are asking.
To Solve Your Actual Problem
There is a way to achieve your desired result of scrolling the element to the top of the view. What you want to do is scroll to the end of the document, then call BringIntoView on the element you want to have at the top.
There are multiple ways a FlowDocument can be displayed in an application. How you handle the scrolling depends on which control you are using to present the FlowDocument.
In a RichTextBox, use the ScrollToEnd method.
In a FlowDocumentScrollViewer, you will need to get its internal ScrollViewer and call ScrollToBottom on it. (You have to wait until the control is loaded before you can get a template part from it.)
private void MyControl_Loaded(object sender, RoutedEventArgs e)
{
mScrollViewer = mViewer.Template.FindName("PART_ContentHost", mViewer) as ScrollViewer;
}
In a FlowDocumentReader, the process is a bit more complex.
When the control is loaded, register for changes to the ViewingMode property and run the handler once to account for the starting value:
private void MyControl_Loaded(object sender, RoutedEventArgs e)
{
var descriptor = DependencyPropertyDescriptor.FromProperty(FlowDocumentReader.ViewingModeProperty, typeof(FlowDocumentReader));
descriptor.AddValueChanged(mReader, (s, a) => Reader_ViewModeChanged());
Reader_ViewModeChanged();
}
In the handler, dig in to find the ScrollViewer. It will only be present when the ViewingMode is set to Scroll:
private void Reader_ViewModeChanged()
{
mScrollViewer = null;
if (mReader.ViewingMode == FlowDocumentReaderViewingMode.Scroll)
{
var contentHost = mReader.Template.FindName("PART_ContentHost", mReader) as DependencyObject;
if (contentHost != null && VisualTreeHelper.GetChildrenCount(contentHost) > 0)
{
var documentScrollViewer = VisualTreeHelper.GetChild(contentHost, 0) as FlowDocumentScrollViewer;
if (documentScrollViewer != null)
{
documentScrollViewer.ApplyTemplate();
mScrollViewer = documentScrollViewer.Template.FindName("PART_ContentHost", documentScrollViewer) as ScrollViewer;
}
}
}
}
Once you have the ScrollViewer, you can call ScrollToBottom on it when desired.
Now, scroll to the bottom of the document, then call BringIntoView on your Run, and it should be at the top of the view.

Does not bring it to the top but just call BringIntoView on the Run. Save a reference to the Run.

It may be late but i still want to share the way i DID it in WPF.
You need an offset to do so.
As the above said: Flow gave you:
flow.ScrollToHome(); // Bottom
But also gave: ScrollToVerticalOffset (get from Rect)
if you have index (offset of the char/line) - you can find it in you saved data or get the TextPointer with flow.Selection.Start/End
TextPointer t_st = flow.Selection.Start;
double offset = flow.Document.ContentStart.GetOffsetToPosition(t_st);
private void gotoOffset(double offset)
{
TextPointer myTextPointer1 = flow.Document.ContentStart.GetPositionAtOffset((int)offset);
flow.Selection.Select(myTextPointer1, myTextPointer1);
flow.Focus();
Rect screenPos2 = myTextPointer1.GetCharacterRect(LogicalDirection.Forward);
double offset2 = screenPos2.Top;
Thread.Sleep(100);
flow.ScrollToVerticalOffset(offset2);
flow.Focus();
}
As the code above, We get the Rect from TextPointer, the Textpointer and get from Offset.
The focus just to make sure to place the cursor in right place.
Sometime the issue happen when you jump to many offset.
I recomment to trigger flow.ScrollToHome(); Before jump (because this ScrollToVerticalOffset true from the start, not any line)

Silverlight DataGrid: Set visibility of control within row details template?

I have an instance where the details template has two main stack panels within it.
One is set to collapsed by default. However upon right click and choosing, that stack panel's visibility is to be triggered. This may occur when the row details are expanded already.
However when the row details are expanded and the right click is chosen to view that stack panel, I'm programmatically changing its visibility to Visible but it's not becoming visible.
Is there a secondary call I need to make to update the UI and force the visibility setting to take?
Here's my code:
private void SetWFHistoryVisibility(bool show)
{
var elements = VisualTreeHelper.FindElementsInHostCoordinates(position, this);
var row = (from element in elements
where element is DataGridRow
select element).FirstOrDefault() as DataGridRow;
if (row != null)
{
DataGridDetailsPresenter presenter = VisualHelper.FindVisualChild<DataGridDetailsPresenter>(row);
if (presenter.Children.Count > 0)
{
var grid = (from el in presenter.Children
where el is Grid
select el).FirstOrDefault() as Grid;
if (grid != null)
{
StackPanel wfgc = grid.FindName("wfGridContainer") as StackPanel;
if (show)
wfc.Visibility = System.Windows.Visibility.Visible;
else
wfc.Visibility = System.Windows.Visibility.Collapsed;
}
}
}
}

You may need to call DataGridView.Refresh(), or equivalent depending on your panel/layout. Also it can be a parent control as well needing to update/refresh.
I know that in Silverlight DataGrid does have an AutoRefresh, but it is primarily controlled by an EventTrigger either in a DGV or DataGrid class. As you discovered it isn't perfect.
Perhaps you can trigger one of the following events and allow the Control to work out it's own view update.
https://msdn.microsoft.com/en-us/library/system.windows.controls.datagrid(v=vs.110).aspx
This one solution:
Dispatcher.BeginInvoke(() => {
//set the added control to be visible
});
Was suggested by a user on MSDN for StackPanel refreshing.
Several other suggestions suggest utilizing a combination of:
_.Invalidate()
_.UpdateLayout()
For forcing a refresh.

C# ComboBox disable highlighting

I have custom ComboBox, where DropDownStyle = ComboBoxStyle.DropDown;.DropDown style is set because I want to set the Text property of the ComboBox to something outside the list of values. Everything works good, except that ComboBox is highlighting the text when it's left and when I click on the combobox editing is avaible. How can I cope with this?
To illustrate:
First Picture is where everything looks good, second is the highlight situation, third editing is on.

Try un-selecting the text after the DropDown closes:
void comboBox1_DropDownClosed(object sender, EventArgs e) {
this.BeginInvoke(new Action(() => { comboBox1.Select(0, 0); }));
}

If you are referring to disabling the highlighting and editing, then you might want to consider setting the DropdownStyle property to DropdownList.
yourComboBox.DropDownStyle = ComboBoxStyle.DropDownList;

Tricky problem to solve. It seems to be from the Resize event. There are a lot of solutions that do something similar to this, but none that I've seen worked for me until I tried this. (This is a solution that does not require inheritance from ComboBox; inheriting is probably a much more straight forward solution, but requires you to always use your inherited class and never the actual ComboBox class.)
comboBox.Resize += (s, e) => {
if (!comboBox.IsHandleCreated)
return; // avoid possible exception
comboBox.BeginInvoke(new Action(() => comboBox.SelectionLength = 0));
};
Set the selection length to zero to get rid of the highlight, but when? Other examples do it in other places, but the problem seems to be specifically caused by Resize, so doing it after Resize fixes it consistently, at least for me. (Can still see it flicker when you resize the window though, but it always ends up ok.)
BeginInvoke ensures that it happens sufficiently after Resize to work, and the check for IsHandleCreated prevents it from being called before the handle is created, in which case BeginInvoke would throw an exception.
This slightly more complex version includes some checks to prevent a focused control from losing highlight, since it actually should have it. It also doesn't fire if the parent doesn't exist yet, or if the parent does not have an active control yet, both signs that things are too early.
comboBox.Resize += (s, e) => {
if (!comboBox.IsHandleCreated)
return;
comboBox.BeginInvoke(new Action(() => {
var parent = comboBox.FindForm();
if (parent == null)
return;
if (parent.ActiveControl == null)
return;
if (parent.ActiveControl == comboBox)
return;
comboBox.SelectionLength = 0;
}));
};
I tried to make a version that would 'preserve' the selection length rather than always set it to zero, but I couldn't get it to synchronize properly. Many Resize events can fire before the BeginInvoke delegates start to fire, so the preserved value will always be overwritten by the broken one. I tried saving them all in a Queue or Stack, but in both cases, I was unable to reverse the ordering (not really sure why, since that makes no sense).

To solve the same I have tried almost EVERYTHING:
setting the DropdownStyle property to DropdownList
this.BeginInvoke(new Action(() => { comboBox1.Select(0, 0); }));
combobox1.SelectionLength = 0;
changing comboBox.TabIndex
Not tried SendKeys.Send("{ESC}"); because it is not a reliable solution
Nothing helped.
The only stable and working solution was to move a focus on another Label control:
label.Focus();
You could also hide that label.

I know this post is old but recently I have the same problem with combobox.
Situation : I have an editable combobox which propose complete words when user write some letters.
But when I want to type a letter, combobox auto highlight the text and the next letter auto replace the previous.
Solution : I use a textbox to avoid any highlight like that:
<ComboBox IsTextSearchEnabled="False" IsEditable="True" x:Name="CMB_ClientName"/>
<TextBox Text="{Binding ElementName=CMB_ClientName, Path=Text}" TextChanged="ComboBoxChange" x:Name="TXT_ClientName"/>
And I generate the textbox TextChanged event :
private void ComboBoxChange(object sender, TextChangedEventArgs e)
{
//Clear ComboBox items
CMB_ClientName.Items.Clear();
//Auto Open DropDownList
CMB_ClientName.IsDropDownOpen = true;
//Get data from database (use entity framework 6.x)
dbEntity.Client.Load();
//Attribute Data to variable
var clients = dbEntity.Client.Local;
foreach (Client client in clients)
{
//If data begin with the texbox text, the data is add to the combobox items list.
if (client.Nom.ToLower().StartsWith(TXT_NomClient.Text.ToLower()))
{
CMB_ClientName.Items.Add(client.Nom);
}
}
}
I know this solution isn't realy beautifull, but it is for me the easiest solution to avoid highlight text and all the solutions in this post don't work for me.
I hope this solution will be helpfull, thanks for reading.
Math.
Ps: My apologies, my English is not very good. I hope you will understand me correctly.

Nothing worked for me ( I want the form to load with no highlighting in any combobox) until I set the combobox property TabStop to false. This meant that one of my buttons took the tab highlight which I didn't like so I set them all to false for start up and adjusted them programatically as needed.

I know this is an old thread, but my solution is similar to that of the others, but relies on the Form.ResizeEnd event. In its event handler, I iterate through the ComboBoxes and set ComboBox.SelectionLength to 0.
private void Form_ResizeEnd(object sender, EventArgs e)
{
foreach(ComboBox comboBox in parentControl.Controls.OfType<ComboBox>
{
comboBox.SelectionLength = 0;
}
}

This is what worked for me:
Set DrawMode to OwnerDrawFixed
Set cbxSubsystems.DrawItem event to the function below
private void cbxSubsystems_DrawItem(object sender, DrawItemEventArgs e)
{
Color BgClr;
Color TxClr;
if( (e.State & DrawItemState.ComboBoxEdit) == DrawItemState.ComboBoxEdit )
{
// Do not highlight main display
BgClr = cbxSubsystems.BackColor;
TxClr = cbxSubsystems.ForeColor;
}
else
{
BgClr = e.BackColor;
TxClr = e.ForeColor;
}
e.Graphics.FillRectangle(new SolidBrush(BgClr), e.Bounds);
TextRenderer.DrawText(e.Graphics, cbxSubsystems.Items[e.Index].ToString(), e.Font, e.Bounds,
TxClr, BgClr, TextFormatFlags.Left | TextFormatFlags.VerticalCenter );
}

How can I set the position of my datagrid scrollbar in my winforms app?

In my C# winforms app, I have a datagrid. When the datagrid reloads, I want to set the scrollbar back to where the user had it set. How can I do this?
EDIT: I'm using the old winforms DataGrid control, not the newer DataGridView

You don't actually interact directly with the scrollbar, rather you set the FirstDisplayedScrollingRowIndex. So before it reloads, capture that index, once it's reloaded, reset it to that index.
EDIT: Good point in the comment. If you're using a DataGridView then this will work. If you're using the old DataGrid then the easiest way to do that is to inherit from it. See here: Linkage
The DataGrid has a protected GridVScrolled method that can be used to scroll the grid to a specific row. To use it, derive a new grid from the DataGrid and add a ScrollToRow method.
C# code
public void ScrollToRow(int theRow)
{
//
// Expose the protected GridVScrolled method allowing you
// to programmatically scroll the grid to a particular row.
//
if (DataSource != null)
{
GridVScrolled(this, new ScrollEventArgs(ScrollEventType.LargeIncrement, theRow));
}
}

Yep, definitely FirstDisplayedScrollingRowIndex. You'll need to capture this value after some user interaction, and then after the grid reloads you'll want to set it back to the old value.
For instance, if the reload is triggered by the click of a button, then in the button click handler, you might want to have as your first line a command that places this value into a variable:
// Get current user scroll position
int scrollPosition = myGridView.FirstDisplayedScrollingRowIndex;
// Do some work
...
// Rebind the grid and reset scrolling
myGridView.DataBind;
myGridView.FirstDisplayedScrollingRowIndex = scrollPosition;

Store your vertical and horizontal scroll values into some variable and reset them.
int v= dataGridView1.VerticalScrollingOffset ;
int h= dataGridView1.HorizontalScrollingOffset ;
//...reload
dataGridView1.VerticalScrollingOffset = v;
dataGridView1.HorizontalScrollingOffset =h;

you can save scroll position with next code
int Scroll;
void DataGridView1Scroll(object sender, ScrollEventArgs e)
{
Scroll = dataGridView1.VerticalScrollingOffset;
}
and you can set scroll of dgv to same position after refresing, load dgv... with next code:
PropertyInfo verticalOffset = dataGridView1.GetType().GetProperty("VerticalOffset", BindingFlags.NonPublic |
BindingFlags.Instance);
verticalOffset.SetValue(this.dataGridView1, Scroll, null);

Just posted the answer on the link given by BFree
The DataGrid has a protected GridVScrolled method that can be used to scroll the grid to a specific row. To use it, derive a new grid from the DataGrid and add a ScrollToRow method.
C# code
public void ScrollToRow(int theRow)
{
//
// Expose the protected GridVScrolled method allowing you
// to programmatically scroll the grid to a particular row.
//
if (DataSource != null)
{
GridVScrolled(this, new ScrollEventArgs(ScrollEventType.LargeIncrement, theRow));
}
}
VB.NET code
Public Sub ScrollToRow(ByVal theRow As Integer)
'
' Expose the protected GridVScrolled method allowing you
' to programmatically scroll the grid to a particular row.
'
On Error Resume Next
If Not DataSource Is Nothing Then
GridVScrolled(Me, New ScrollEventArgs(ScrollEventType.LargeIncrement, theRow))
End If
End Sub

I used the answer by #BFree, but also needed to capture the first visible row in the DataGrid:
int indexOfTopMostRow = HitTest(dataGrid.RowHeaderWidth + 10,
dataGrid.PreferredRowHeight + 10).Row;

Even though this is an old question, Many of the solutions above did not work for me. What worked ultimately was:
if(gridEmployees.FirstDisplayedScrollingRowIndex != -1) gridEmployees.FirstDisplayedScrollingRowIndex = 0;