We Keep Coding

FlowLayoutPanel shows horizontal scroll bar with inner panel's width being the same as client size width

I'm experiencing a problem with FlowLayoutPanel while its children being resized on FlowLayoutPanel's ClientSizeChanged event.
I'm trying to make the children resize horizontally when the FlowLayoutPanel resizes. The problem is that even though the margin of the child is 0 and the padding of FlowLayoutPanel is also 0, after the execution of ClientSizeChanged event handler, the FlowLayoutPanel shows its horizontal scroll bar while the width of the child is exactly the same as FlowLayoutPanel.ClientSize.Width.
I've tried to move the code to Resize event, but I still get the same result.
This is an example to demonstrate the problem, there's one FlowLayoutPanel with the following properties changed from default:
AutoScroll = true
FlowDirection = TopDown
Margin = 0,0,0,0
Name = flow1
BackColor = Red
There's also a regular panel inside the FlowLayoutPanel:
Margin = 0,0,0,0
Name = panel1
BackColor: Blue
And finally, a timer with interval 1 which changes the width of the FlowLayoutPanel and disables itself when the HorizontalScroll.Visibile property of the FlowLayoutPanel is true and shows a message box that announces the width of panel1 and ClientSize.Width of the flow1.
Here's the code:
private void timer1_Tick(object sender, EventArgs e)
{
flow1.Width -= 1;
if (flow1.HorizontalScroll.Visible)
{
timer1.Enabled = false;
MessageBox.Show("Panel.Width = " + panel1.Width.ToString() +
", FlowPanel.ClientWidth = " + flow1.ClientSize.Width.ToString());
}
}
private void flow1_ClientSizeChanged(object sender, EventArgs e)
{
panel1.Width = flow1.ClientSize.Width;
}
What's the logic behind the horizontal scroll bar being shown while no children overflows the client size? And most importantly, how to prevent it from happening?

It is an event order problem, the layout gets calculated too soon. Automatic layout has several nasty corner-cases, it can also be bi-stable with the layout flipping back-and-forth between two solutions. You can see this in your test app, add flow1.PerformLayout(); before the MessageBox.Show() call and you'll see that the scrollbar is hidden again.
This is why the SuspendLayout() method exists. Winforms programmers don't use it enough. For a good reason, it is pretty hard to judge when you need it. And they really don't want to need it. Basic rule is that you should use it if layout must deal with more than one size changing.
Which is the real fix in your test program:
private void timer1_Tick(object sender, EventArgs e) {
flow1.SuspendLayout();
flow1.Width -= 1;
flow1.ResumeLayout(true);
// etc..
}
And you'll see that it works just fine now, you never see the message box.

How to hide and show panels on a form and have it resize to take up slack?

I have a form with three panels.
I want the top two to be a fixed height, and bottom one to fill the rest of the space.
The dialog is resizable, so all should change width on resixze, and bottom one should change height.
This is important, the user must be able to stretch the form, as well as the program through code.
If I set a panel to visible = false, I want the form height to shrink so the others stay the same height.
If I set a panel to visible = true, I want the form height to grow by the height of the panel.
I will control the hiding/showing of the panels with buttons. The idea is I show certain panels for "advanced" mode in my form, and hide them for "simple" mode. I cannot have a bunch of blank space if I hide a panel, and I want the form to shrink a bunch for simple mode.
I tried doing this with panels docked to top, but a form resize by the user will not change a panel height. So that is the main trick I am asking for help on.

Anyone in this kind of situation can use the below styling:
Use 2-3 Panel to Group different Controls and place them in a single parent control say a GroupBox.
Make all the child panels Dock to the same side say "Top".
if any of the panel is jumping over another due to similar docking. In Visual Studio, go to menu View > Other Windows > Document Outline and Set the display order. (https://msdn.microsoft.com/en-us/library/46xf4h0w%28v=vs.80%29.aspx)
Set the Panel property as follows:
AutoSize: true
AutoSizeMode: GrowAndShrink
Once the panel is not visible, other panel will take away the empty space.
Hope this helps!!!

the other posts are close, there is a detail missing that I included in the solution I came up with. Its a flag to tell if the sized event was caused by a user form resize, or the program doing it when a panel is shown or hidden.
For this solution, make a form with 4 panels.
Set dock to top for all panels. Do not set any autosizing for panels or form.
Also make two buttons and place on top panel, or any panel that you will not be hiding.
The code below shows how to handle the resized event, and the showing hiding buttons.
I made them hide/show panel 2, but the code should work for any panel.
namespace ProgTesting {
public partial class Form5 : Form {
private bool doNothing = false;
public Form5() {
InitializeComponent();
cmdAdvanced.Visible = false;
}
private void cmdSimple_Click(object sender, EventArgs e) {
if (panel2.Visible) {
panel2.Visible = false;
doNothing = true;
this.MinimumSize = new Size(this.Width, this.Height - panel2.Height);
this.Height = this.Height - panel2.Height;
doNothing = false;
cmdSimple.Visible = false;
cmdAdvanced.Visible = true;
}
}
private void cmdAdvanced_Click(object sender, EventArgs e) {
if (!panel2.Visible) {
panel2.Visible = true;
doNothing = true;
this.Height = this.Height + panel2.Height;
this.MinimumSize = new Size(this.Width, this.Height);
doNothing = false;
cmdAdvanced.Visible = false;
cmdSimple.Visible = true;
}
}
private void Form5_SizeChanged(object sender, EventArgs e) {
if (!doNothing)
if (panel2.Visible)
panel3.Height = this.ClientSize.Height - panel1.Height - panel2.Height - panel4.Height;
else
panel3.Height = this.ClientSize.Height - panel1.Height - panel4.Height;
}
}
}
You do have to manage the heights going on, which is a pain but gives you control. Some shots of it working:

It sounds like what you are looking for is an Expander. Essentially a control that consists of a header and a content area, where clicking on the header toggles the content area between visible and collapsed.
I'm not 100% certain if an Expander control will automatically adjust the height of a form when it expands/collapses though. You may need to hook up an event handler to the Expander to manually adjust the height of your form when the Expander collapses.
Try looking at the Stack Overflow Question Add an expander (collapse/expand) to a Panel WinForm. There are a number of links from that question about implementing an Expander in Windows Forms, including some that provide full source code.
Update:
I've knocked up a quick demo that will accomplish what you want, in a very primitive way, not using any of the various Expander controls out there. I think that while you will find the Expanders useful, I doubt they will adjust the size of the container they are inside, unless you write some adjustment code like I have below.
Create a form that looks like this:
The two text boxes are anchored Left, Top, Right.
The toggle button is anchored Left, Top, named btnTogglePanel.
The magenta panel is anchored Left, Top, Right, Bottom, named pnlToggled.
The bottom button is anchored Right, Bottom.
Then in the code behind for the form:
public partial class ToggleableExpanderForm : Form
{
public ToggleableExpanderForm()
{
InitializeComponent();
SizeChanged += (s, args) =>
{
if (_LastSize.HasValue)
{
var diff = Size - _LastSize.Value;
if (_LastHeight.HasValue
&& !IgnoreNextResizeForLastHeightAdjustment)
{
_LastHeight += diff.Height;
}
}
_LastSize = Size;
};
}
private Size? _LastSize;
private bool IgnoreNextResizeForLastHeightAdjustment = true;
private int? _LastHeight;
private void btnTogglePanel_Click(object sender, EventArgs e)
{
var newVisibility = !pnlToggled.Visible;
int heightAdjustment = 0;
if (newVisibility)
{
if (_LastHeight.HasValue)
{
heightAdjustment = _LastHeight.Value;
_LastHeight = null;
}
}
else
{
_LastHeight = pnlToggled.Height;
heightAdjustment = -pnlToggled.Height;
}
pnlToggled.Visible = newVisibility;
IgnoreNextResizeForLastHeightAdjustment = true;
Height += heightAdjustment;
}
}
Essentially you adjust the height of the form manually when the toggle button is clicked, based on whether or not the panel is hiding/showing. You also need to take into account of what will happen when the user resizes the form when the panel is invisible, which is where the cruft around listening to the SizeChanged event comes in. You need the answer to "how MUCH has the size changed" and then you adjust your previously stored panel height as appropriate.
I don't imagine the above code is perfect, and I haven't tested it in every use case, but it gets the basic job done.

One way to go about it is to use a TableLayoutPanel for the top two panels.
The steps below will give you the resizing desired when the user resizes the form.
Start by created a TableLayoutPanel (TLP) and shrink it down from the default 2 columns, 2 rows to just 2 columns, 1 row.
Anchor it to Top, Left, and Right
Now size the TLP to fit your top two panels and place each panel in a cell of the TLP.
Anchor these two panels to all sides.
Position the 3rd panel (Panel3) below the TLP to your liking and anchor it to all sides.
To handle the hiding of Panel3 some logic will need to be added to the appropriate button_Click event. Determine what size you would like the "minimized" height to be and then just store the form size when Panel3 is visible and restore the height when it's clicked again. It should look something like this.
private void button1_Click(object sender, EventArgs e)
{
if (panel3.Visible)
{
// make invisible
panel3.Visible = false;
// storedHeight is a private member of the Form
storedHeight = Form1.ActiveForm.Height;
Form1.ActiveForm.Height = minimumHeight; // Set to predetermined minimum height
}
else
{
// make visible
panel3.Visible = true;
Form1.ActiveForm.Height = storedHeight;
}
}
Now when you hide Panel3 the form will shrink to the size of the TLP, then grow again when Panel3 is visible. Also the top panels will expand in width, but not height. You will need to change the MinSize properties of the form and its value will have to be dynamically adjusted depending on whether Panel3 is visible or not.

How to make Tab pages' widths fit into the TabControl's width

I have a TabControl with two tab pages.
How can I make the tab pages fit into the width of the TabControl like shown in the below screenshot.
I tried with the following line of code but it does not work either.
tabControl1.SizeMode = TabSizeMode.FillToRight;

First, set your tabControl1 size mode:
tabControl1.SizeMode = TabSizeMode.Fixed;
Then you have to recalculate width of the tab page header:
tabControl1.ItemSize = new Size(tabControl1.Width / tabControl1.TabCount, 0);
Pay attention: 1. value 0 means that height will be default. 2. Recalculate item size after you had added tab page to tab control. Consider what happens when you resize the control.

Contributing based on Jarek's answer. If you want tabs widths to change dynamically as you resize the TabControl as well, you can achieve this by implementing this on the TabControl Resize Event:
private bool doNotExecuteResizeEventAgain = true;
private void Tab_Control_Resize(object sender, EventArgs e)
{
if(doNotExecuteResizeEventAgain)
{
int tabWidth = ((int)(tab_Control.Width/tab_Control.TabPages.Count)) - 1;
doNotExecuteResizeEventAgain = false;
tab_Control.ItemSize = new Size(tabWidth, tab_Details.ItemSize.Height);
doNotExecuteResizeEventAgain = true;
}
}
The use of the variable doNotExecuteResizeEventAgain is because the ItemSize calls again the event Resize, so in order to stop it from cycling, I added that flag.

Use SizeMode on the TabControl: http://msdn.microsoft.com/en-us/library/system.windows.forms.tabcontrol.sizemode.aspx

this is illegal way to solve this kind of issue
Increase the padding (X,Y)
X 100 // represent some allowed figures
Y 3 // represent some allowed figure.

Change the Textbox height?

How do I change the height of a textbox ?
Neither of the below work:
this.TextBox1.Size = new System.Drawing.Size(173, 100);
or
this.TextBox1.Size.Height = 100;
I wanted to be able to change the single line text box height to fit a font size on it without using multi-line if possible.

Go into yourForm.Designer.cs
Scroll down to your textbox. Example below is for textBox2 object.
Add this
this.textBox2.AutoSize = false;
and set its size to whatever you want
this.textBox2.Size = new System.Drawing.Size(142, 27);
Will work like a charm - without setting multiline to true, but only until you change any option in designer itself (you will have to set these 2 lines again).
I think, this method is still better than multilining. I had a textbox for nickname in my app and with multiline, people sometimes accidentially wrote their names twice, like Thomas\nThomas (you saw only one in actual textbox line). With this solution, text is simply hiding to the left after each char too long for width, so its much safer for users, to put inputs.

There are two ways to do this :
Set the textbox's "multiline" property to true, in this case you don't want to do it so;
Set a bigger font size to the textbox
I believe it is the only ways to do it; the bigger font size should automatically fit with the textbox

You can set the MinimumSize and/or the MaximumSize properties of the textbox. This does not affect the size immediately, but when you resize the textbox in the forms designer, the size will automatically be adjusted to satisfy the minimum/maximum size constraints. This works even when Multiline is set to false and does not depend on the font size.

Just found a great little trick to setting a custom height to a textbox.
In the designer view, set the minimumSize to whatever you desire, and then completely remove the size setting. This will cause the designer to update with the new minimum settings!

set the minimum size property
tb_01.MinimumSize = new Size(500, 300);
This is working for me.

Try the following :)
textBox1.Multiline = true;
textBox1.Height = 100;
textBox1.Width = 173;

Steps:
Set the textboxes to multiline
Change the height
Change the font size. (so it fit into the big textboxes)
Set the textboxes back to non-multiline

public partial class MyTextBox : TextBox
{
[DefaultValue(false)]
[Browsable(true)]
public override bool AutoSize
{
get
{
return base.AutoSize;
}
set
{
base.AutoSize = value;
}
}
public MyTextBox()
{
InitializeComponent();
this.AutoSize = false;
}
}

May be it´s a little late. But you can do this.
txtFoo.Multiline = true;
txtFoo.MinimumSize = new Size(someWith,someHeight);
I solved it that way.

AutoSize, Minimum, Maximum does not give flexibility. Use multiline and handle the enter key event and suppress the keypress. Works great.
textBox1.Multiline = true;
private void textBox1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Enter)
{
e.Handled = true;
e.SuppressKeyPress = true;
}
}

You can put it inside a panel that has the same back color with your desired height. This way has this advantage that the text box can center horizontally, which is not provided by other solutions.
You can make it even more natural by using the following methods
private void textBox1_Enter(object sender, EventArgs e)
{
panelTextBox.BorderStyle = BorderStyle.FixedSingle;
}
private void textBox1_Leave(object sender, EventArgs e)
{
panelTextBox.BorderStyle = BorderStyle.None;
}

The Simplest Way to do that
Right click on the TextBox.
Go to properties.
Set Multiline = True.
Now you will be able to resize the TextBox vertically as you wish.

for me, the best approach is remove border of the textbox, and place it inside a Panel, which can be customized as you like.

The following code added in your constructor after calling InitializeComponent() will make it possible to programmatically set your text box to the correct height without a) changing the Multiline property, b) having to hardcode a height, or c) mucking with the Designer-generated code. It still isn't necessarily as clean or nice as doing it in a custom control, but it's fairly simple and robust:
if (txtbox.BorderStyle == BorderStyle.None)
{
txtbox.BorderStyle = BorderStyle.FixedSingle;
var heightWithBorder = txtbox.ClientRectangle.Height;
txtbox.BorderStyle = BorderStyle.None;
txtbox.AutoSize = false;
txtbox.Height = heightWithBorder;
}
I decided to make it cleaner and easier to use by putting it in a static class and make it an extension method on TextBox:
public static class TextBoxExtensions
{
public static void CorrectHeight(this TextBox txtbox)
{
if (txtbox.BorderStyle == BorderStyle.None)
{
txtbox.BorderStyle = BorderStyle.FixedSingle;
var heightWithBorder = txtbox.ClientRectangle.Height;
txtbox.BorderStyle = BorderStyle.None;
txtbox.AutoSize = false;
txtbox.Height = heightWithBorder;
}
}
}

Some of you were close but changing designer code like that is annoying because you always have to go back and change it again.
The original OP was likely using an older version of .net because version 4 autosizes the textbox height to fit the font, but does not size comboboxes and textboxes the same which is a completely different problem but drew me here.
This is the problem I faced when placing textboxes next to comboboxes on a form. This is a bit irritating because who wants two controls side-by-side with different heights? Or different fonts to force heights? Step it up Microsoft, this should be simple!
I'm using .net framework 4 in VS2012 and the following was the simplest solution for me.
In the form load event (or anywhere as long as fired after InitializeComponent): textbox.AutoSize = false Then set the height to whatever you want. For me I wanted my text boxes and combo boxes to be the same height so textbox.height = combobox.height did the trick for me.
Notes:
1) The designer will not be affected so it will require you to start your project to see the end result, so there may be some trial and error.
2) Align the tops of your comboboxes and textboxes if you want them to be aligned properly after the resize because the textboxes will grow down.

This is what worked nicely for me since all I wanted to do was set the height of the textbox. The property is Read-Only and the property is in the Unit class so you can't just set it. So I just created a new Unit and the constructor lets me set the height, then set the textbox to that unit instead.
Unit height = txtTextBox.Height;
double oldHeight = height.Value;
double newHeight = height.Value + 20; //Added 20 pixels
Unit newHeightUnit = new Unit(newHeight);
txtTextBox.Height = newHeightUnit;

You can make multiline : false and then just change the text size on the text box then the height will automatically increment

you can also change you can also change MinimumSize

So after having the same issue with not being able to adjust height in text box, Width adjustment is fine but height never adjusted with the above suggestions (at least for me), I was finally able to take make it happen. As mentioned above, the issue appeared to be centered around a default font size setting in my text box and the behavior of the text box auto sizing around it. The default font size was tiny. Hence why trying to force the height or even turn off autosizing failed to fix the issue for me.
Set the Font properties to the size of your liking and then height change will kick in around the FONT size, automatically. You can still manually set your text box width. Below is snippet I added that worked for me.
$textBox = New-Object System.Windows.Forms.TextBox
$textBox.Location = New-Object System.Drawing.Point(60,300)
$textBox.Size = New-Object System.Drawing.Size(600,80)
$textBox.Font = New-Object System.Drawing.Font("Times New Roman",18,[System.Drawing.FontStyle]::Regular)
$textBox.Form.Font = $textbox.Font
Please note the Height value in '$textBox.Size = New-Object System.Drawing.Size(600,80)' is being ignored and the FONT size is actually controlling the height of the text box by autosizing around that font size.

All you have to do is enable the multiline in the properties window, put the size you want in that same window and then in your .cs after the InitializeComponent put txtexample.Multiline = false; and so the multiline is not enabled but the size of the txt is as you put it.
InitializeComponent();
txtEmail.Multiline = false;
txtPassword.Multiline = false;

I think this should work.
TextBox1.Height = 100;

Repaint of panel

My problem is that I have a panel in panel. Inside i have the AutoScroll property set to true. When I open a new window this panel is scrolled to begining.
I do that, I save the position before open new window, and I set it after close it. It works but it jumps to the beginning and then back to my position.

The AutoScrollPosition property is a bit funny. When you read it, it will return the current scroll offset, but when you assign it you will need to invert the values:
private static Point GetAutoScrollPosition(Panel panel)
{
return panel.AutoScrollPosition;
}
private static void SetAutoScrollPosition(Panel panel, Point position)
{
panel.AutoScrollPosition = new Point(-position.X, -position.Y);
}
Now you can retrieve the current position and set it like so:
Point pos = GetAutoScrollPosition(myPanel);
SetAutoScrollPosition(myPanel, pos);

Have you tried setting autoscroll to false?

I do something lik You wrote
_scrollPozition = -(pnlMain.AutoScrollPosition.Y);
DialogResult result = MessageBox.Show("Delete: ", MessageBoxButtons.YesNo);
dgvClendar.Focus();
private void pnlMain_Paint(object sender, PaintEventArgs e)
{
if (pnlMain.AutoScrollPosition.Y == 0)
{
pnlMain.AutoScrollPosition = new Point(0, _scrollPozition);
_scrollPozition = 0;
}
}
on paint it is set, but if you look everything is moved for a moment. I need to block this scroll to begin, or block painting, and repaint after scroll to current position.