I'm working on winfom application c#.
I have two forms called Welome and Details.
Details contains 7 grids in the Panel.
Scenario:
If I click on any of the item on welcome page it will take to the Details page with seven grids. If I drag the scroll bar down, and come back after moving back to welcome form, still the scroll bar stays at the same position.
Question:
I want to reset the scroll position to top each time the user visits the details form, so that I can always see first grid.
Set AutoScroll to true
panel1.AutoScroll = true;
And, then in Details form's load event, set the VerticalScroll
panel1.VerticalScroll.Value = 0;
If Angshuman Agarwal's answer doesn't work for you, the culprit is likely that after load some control in the form is receiving focus, which will scroll into view and override any changes to the scroll position.
You could set TabStop to false, but then your form wouldn't be tabbable :(
A clunky work-around, but still relatively simple fix, is manually fire focus on the first control in your form:
yourFirstControl1.Select();
See also: How to make the panel scroll bar to be at the TOP position on loading the form
Old post, but still relevant. The above only worked when I added a line:
displayPanel.AutoScroll = true;
displayPanel.AutoScrollPosition = new Point(displayPanel.AutoScrollPosition.X, 0);
displayPanel.VerticalScroll.Value = 0;
Then it worked great, without having to set any tab indexes.
What is mentioned above is fine but, you should add VerticalScroll.Value in Panel1_Paint
Private Sub Panel1_Paint(sender As Object, e As PaintEventArgs) Handles Panel1.Paint
Panel1.VerticalScroll.Value = 0
End Sub
Related
A Quick Note
I've tried to be as thorough as possible with my question but you may still need additional clarification; if this happens to be the case, feel free to comment your concerns and I will update the post to answer them as best as I can.
I came across a rather odd issue yesterday when toggling controls on my form. I have a period of loading on FormShown and all controls but the loading display should be hidden. The toggle works to turn visibility off for everything but the loading display, but when loading completes only some of the controls are visible.
I stepped through the code that turns everything back to visible and ensured that everything is indeed being set to Visible = true. I think it may have something to do with the Dock property on the controls, or maybe the TabIndex or something similar but I'm having trouble tracking the underlying issue down.
This is the code I use to toggle the control visibility:
private void ToggleAllControlVisibility() {
foreach (Control c in Controls)
ToggleControlVisibility(c);
}
private void ToggleControlVisibility(Control c) {
if (c.Name == "loadingContainer")
return;
if (!(c is SplitContainer || c is SplitterPanel))
c.Visible = !c.Visible;
foreach (Control child in c.Controls)
ToggleControlVisibility(child);
}
It is a recursive toggle in which all child controls are also toggled. The ToggleAllControlVisibility method is called before loading begins, and again after loading completes.
A More Detailed Look
Now that you know the problem, there are certain controls in particular that I know do not show (at least the way they should). Take the following control tree for example:
pTimePanel (Panel)
timeSlider (TrackBar)
lblStartTime (Label)
lblStopTime (Label)
Out of the controls above, only the pTimePanel actually displays in the foreground. I believe its child controls may be displaying behind it somehow because as I step through the code and it reaches the lblStartTime control, I can briefly see the outline of the label (no content) and then when it moves to the next control it's gone. The timeSlider control doesn't seem to show the same behavior but it does get back to Visible = true.
The full tree from form to the above controls (with docking properties) is as below:
splitContainer : Dock-Fill
panel1 (SplitterPanel)
loadingPanel (Panel) : Dock-Fill
pTimePanel (Panel) : Dock-Bottom
pTimeLabels (Panel) : Dock-Bottom
lblStartTime (Label) : Dock-Left
lblStopTime (Label) : Dock-Right
timeSlider (TrackBar) : Dock-Fill
Notes
Some of these may be less helpful than others, but as I think of things that may help clarify what's going on, I'll add them here.
When visibility is toggled in either direction, the Resize event on the loadingPanel is raised.
Question
What could possibly be occurring to make this odd behavior possible?
It turns out that this was related to the order in which the controls were added to the form. Due to some copying and pasting controls a while back things ended up in an improper order. I had to rebuild the form from scratch to get any toggling to actually work. Once I rebuilt the form, all of the available options for toggling began working the way I expected them to.
My issue is in the .NET framework using C# to create a simple form application that contains a rich text box (RTB) control.
Briefly the issue I am experiencing is that when trying to clear the contents (.Text) of the RTB, the scroll bar doesn't go away. I would like to know if there is anything inherently wrong with the way I am using the RTB. I apologize, but the site will not allow me to post images yet. So if there is a misunderstanding regarding what "doesn't go away" means, please ask!
So first, I write data to the box using the following code snippet:
// append the new message
this.rtb_receive_0.Text += message;
this.rtb_receive_0.SelectionStart = this.rtb_receive_0.Text.Length;
this.rtb_receive_0.ScrollToCaret();
Later on, I clear the RTB contents (RTB.Text) with the following code:
this.rtb_receive_0.Text = String.Empty;
this.rtb_receive_0.Refresh();
In the above code I have attempted to fix my problem with the, "Refresh," method. However it does not seem to be doing the job.
When I clear the RTB contents, the scroll bar does not go away... I noticed that if I grab another window and drag it over the top of the application, that the frozen scroll bar disappears. Also, I can minimize the application, then maximize it again and the bar will disappear. There has to be a way to prevent this frozen scroll bar from happening in the first place though.
Per the answer, here was the fix to stop the bar from freezing up:
this.rtb_receive_0.Text = String.Empty;
this.rtb_receive_0.Clear();
this.rtb_receive_0.ScrollBars = RichTextBoxScrollBars.None;
this.rtb_receive_0.ScrollBars = RichTextBoxScrollBars.Vertical;
this.rtb_receive_0.Refresh();
Have you tried simply just programatically setting the Scrollbars property on the RTB?
myRichTextBox.ScrollBars = RichTextBoxScrollBars.None;
Edit: I think I misinterpreted what you needed. Searching around, I found this similar post on another forum: http://www.vbforums.com/showthread.php?793671-RESOLVED-RichTextBox-Visual-Bug
This user is setting the value of an RTB based on a selection in a list view. When a new value is set and does not require a scrollbar it doesn't re-draw and still shows the bar.
It seems like adding myRichTextBox.Clear(); myRichTextBox.Refresh(); should help. In this case that user is also programatically setting the ScrollBars property as well.
Also, are you able to determine how many lines of text can fit in the RichTextBox before a scrollbar is needed? I suppose that might vary based on system settings on the machine, but you might just be able to programatically check myrtb.Scrollbars = (myrtb.Lines.Length > X) ? Vertical : None; (excuse the psuedo code syntax)
What helped for me was just calling the refresh() method twice. Very ugly, but it does the job.
Hmm, after more thorough testing this ugly fix proved to be not so much of a fix afterall. It helps, but still some glitches.
refresh();
update();
seems like a better solution.
I was having this same problem. I solved it by calling the Invalidate() method which forces the control to repaint.
Me.RichTextBox.Clear()
'Call Invalidate in order to force the RichTextBox to repaint. I do this so that any
'Visible Scroll bars are removed after clearing the Text
Me.RichTextBox.Invalidate()
I tried with Refresh(); Update(); Invalidate();,but it didn't worked for me.
I solved this problem using following three lines :-
RitchTextBox.Clear(); //Clearing text in RichTextBox
RitchTextBox.ScrollBars = RichTextBoxScrollBars.None; //Remove scroll
RitchTextBox.ScrollBars = RichTextBoxScrollBars.Vertical; //Again add scroll
Try those above three lines. It will work 100%.
I have a very basic out the box mdiparent which has a number of mdichildren and a menu item. Each button on the menu item hides all the forms and then shows the one respective to that button.
When I do it this way:
//dontHide is the Form we want to show.
for(int i = 0; i < this.MdiChildren.Length; i++)
{
if (this.MdiChildren[i] != dontHide)
{
this.MdiChildren[i].Visible = false;
}
}
dontHide.Visible = true;
Switching forms causes the new form opened to be positioned bit lower and to the right of the old form, but clicking the menu item for the currently displayed form does nothing (as expected).
But, when I do this:
//dontHide is the Form we want to show.
for(int i = 0; i < this.MdiChildren.Length; i++)
{
this.MdiChildren[i].Visible = false;
}
dontHide.Visible = true;
Even clicking the menu item for the currently visible form causes it to shift to the lower right, same as opening a new form. Why is that?
Edit:
I've also noticed when centering the form and then displaying it (so you don't risk having someone glimpse it right before it is moved), setting visible to true completely resets any centering I've done.
This is caused by an obscure implementation detail in Winforms. The native MDI support built into Windows does not support hiding child windows. Winforms works around this restriction by destroying the child window when you set its Visible property to false. And re-creating it when you set it back to true.
This can have various side-effects, the state of the native window is lost when this happens of course. Winforms has fairly decent support for restoring the window again from its properties. But one thing it doesn't do is recreating the window in the same location. So you'll see it getting recreated in the location that new MDI child windows get, staggered from the previous window. Whether that was an oversight or intentional isn't that clear to me, 95% odds for the latter.
Otherwise simple to work around, you can assign the Location property yourself to get it back where it was:
var loc = dontHide.Location;
dontHide.Visible = true;
dontHide.Location = loc;
Or just set the MDI child form's StartPosition to Manual.
I'm having a difficulty in sizing my form!
I dynamically create buttons on a form and need to know if they are all fully visible or if I need to grow the form and in what direction to make all the buttons fully visible.
I don't want to use the autosize property as I need to control the layout.
So how do I tell if a dynamically created controls bounds are within that of the form?
thanks
This a .Net 4 classic forms app.
When you add the button to the controls collection, to see if it is visible check the contains on the forms bounds - Form.Bounds.Contains(button.Bounds));. If that returns false then you need grow your form. Here is some basic code to do the form growing, it will not necessarily produce the prettiest output and is not necessarily the best way, just written to give you a quick idea of how it could be accomplished.
// Add the control
form.Controls.Add(button);
var formBounds = form.Bounds;
var controlBounds = button.Bounds;
if (!formBounds.Contains(controlBounds))
{
formBounds.Left = Math.Min(controlBounds.Left, formBounds.Left);
formBounds.Right = Math.Max(controlBounds.Right, formBounds.Right);
// Do similar for top and bottom this will ensure your button is visible
form.Bounds = formBounds;
}
Can you add the button, can't you compare the Width of the container vs the Left + Width properties of the newly added button?
I wish to have a Panel with the controls on it at design time but I want to add this panel to a desired tabPage of my TabControl at run time.
I wrote something like this, did not work : the panel does not show up in the tab page.
please help me.
panel2.Parent = tabGuy.TabPages[0];
tabGuy.SuspendLayout();
tabGuy.TabPages[0].Controls.Add(panel2);
tabGuy.ResumeLayout();
panel2.Show();
You probably need to set the coordinates of the Panel as well, or (better) panel2.Dock = DockStyle.Fill;
And you don't have to set the .Parent or call the .Show()