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Scrolling to the bottom of page with invisible scrollbars [duplicate]

I have a panel1 with AutoScroll = true.I have to make panel1 scroll with btnUp and btnDown. So far I've made what I was asked for
private void btnUpClicked(Object sender, EventArgs e)
{
if (panel1.VerticalScroll.Value - 55 > 0)
panel1.VerticalScroll.Value -= 55;
else panel1.VerticalScroll.Value = 0;
}
private void btnDownClicked(Object sender, EventArgs e)
{
panel1.VerticalScroll.Value += 55;
}
But now I need to hide Scrollbar or make it invisible. I tried
panel1.VerticalScroll.Visible = false;
but it doesn't work. Any ideas guys?

Ok, I've done the working example of this for you. All you have to do is to change the max value depending on the total size of all the items inside your panel.
Form code:
public partial class Form1 : Form
{
private int location = 0;
public Form1()
{
InitializeComponent();
// Set position on top of your panel
pnlPanel.AutoScrollPosition = new Point(0, 0);
// Set maximum position of your panel beyond the point your panel items reach.
// You'll have to change this size depending on the total size of items for your case.
pnlPanel.VerticalScroll.Maximum = 280;
}
private void btnUp_Click(object sender, EventArgs e)
{
if (location - 20 > 0)
{
location -= 20;
pnlPanel.VerticalScroll.Value = location;
}
else
{
// If scroll position is below 0 set the position to 0 (MIN)
location = 0;
pnlPanel.AutoScrollPosition = new Point(0, location);
}
}
private void btnDown_Click(object sender, EventArgs e)
{
if (location + 20 < pnlPanel.VerticalScroll.Maximum)
{
location += 20;
pnlPanel.VerticalScroll.Value = location;
}
else
{
// If scroll position is above 280 set the position to 280 (MAX)
location = pnlPanel.VerticalScroll.Maximum;
pnlPanel.AutoScrollPosition = new Point(0, location);
}
}
}
Picture example:
You have to set AutoScroll option to False on your panel. I hope you understand what I've done and will get your panel running the way you want. Feel free to ask if you have any questions.

The Panel control takes on the duty you gave it by setting AutoScroll to true pretty serious. This always includes displaying the scrollbar gadget if it is necessary. So what you tried cannot work, hiding the vertical scrollbar forces Panel to recalculate layout since doing so altered the client area. It will of course discover that the scrollbar is required and promptly make it visible again.
The code that does this, Panel inherits it from ScrollableControl, is internal and cannot be overridden. This was intentional.
So using AutoScroll isn't going to get you anywhere. As an alternative, do keep in mind what you really want to accomplish. You simply want to move controls up and down. Easy to do, just change their Location property. That in turn is easiest to do if you put the controls on another panel, big enough to contain them. Set its AutoSize property to True. And implement you buttons' Click event handlers by simply changing that panel's Location property:
private const int ScrollIncrement = 10;
private void ScrollUpButton_Click(object sender, EventArgs e) {
int limit = 0;
panel2.Location = new Point(0,
Math.Min(limit, panel2.Location.Y + ScrollIncrement));
}
private void ScrollDownButton_Click(object sender, EventArgs e) {
int limit = panel1.ClientSize.Height - panel2.Height;
panel2.Location = new Point(0,
Math.Max(limit, panel2.Location.Y - ScrollIncrement));
}
Where panel1 is the outer panel and panel2 is the inner one that contains the controls. Be careful when you use the designer to put controls on it, it has a knack for giving them the wrong Parent. Be sure to use the View + Other Windows + Document Layout helper window so you can see this going wrong. After you filled it, set its AutoSizeMode property to GrowAndShrink so it snaps to its minimum size.

Try this:
panel.AutoScroll = true;
panel.VerticalScroll.Enabled = false;
panel.VerticalScroll.Visible = false;
Edit:
Actually when AutoScroll = true; It will take care of hscroll and vscroll automatically and you wont be able to change it. I found this on Panel.AutoScroll Property on MSDN
AutoScroll maintains the visibility of the scrollbars automatically. Therefore, setting the HScroll or VScroll property to true has no effect when AutoScroll is enabled.
You may try this to workaround this problem, I have copied it from this Link.
Behavior Observations 1:
If AutoScroll is set to true, you can't modify anything in VerticalScroll or HorizontalScroll. AutoScroll means AutoScroll; the control decides when scrollbars are visible, what the min/max is, etc. and you can't change a thing.
So if you want to customize the scrolling (e.g. hide scrollbars), you must set AutoScroll to false.
Looking at the source code for the ScrollableControl with Lutz Roeder's .NET Reflecter, you can see that if AutoScroll is set to true, it ignores your attempts to change property values within the VerticalScroll or HorizontalScroll properties such as MinValue, MaxValue, Visible etc.
Behavior Observations 2:
With AutoScroll set to false, you can change VerticalScroll.Minimum, VerticalScroll.Maximum, VerticalScroll.Visible values.
However, you cannot change VerticalScroll.Value!!! Wtf! If you set it to a non-zero value, it resets itself to zero.
Instead, you must set AutoScrollPosition = new Point( 0, desired_vertical_scroll_value );
And finally, SURPRISE, when you assign positive values, it flips them to negative values, so if you check AutoScrollPosition.X, it will be negative! Assign it positive, it comes back negative.
So yeah, if you want custom scrolling, set AutoScroll to false. Then set the VerticalScroll and HorizontalScroll properties (except Value). Then to change the scroll value, you need to set AutoScrollPosition, even though you aren't using auto scrolling! Finally, when you set the AutoScrollPosition, it will take on the opposite (i.e. negative) value that you assign to it, so if you want to retrieve the current AutoScrollPosition later, for example if you want to offset the scroll value by dragging the mouse to pan, then you need to remember to negate the value returned by AutoScrollPosition before reassigning it to AutoScrollPosition with some offset. WOW. Wtf.
One other thing, if you are trying to pan with the mouse, use the values of Cursor.Position rather than any mouse locations returned by the mouse events parameters. Scrolling the control will cause the event parameter values to be offset as well, which will cause it to start firing mouse move events complete with undesired values. Just use Cursor.Position, because it will use mouse screen coordinates as a fixed frame of reference, which is what you want when you're trying to pan/offset the scroll value.

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.

TableLayoutPanel displays vertical scroll

I have TableLayoutPanel for dynamic creation of controls with AutoScroll = true. It's work fine when I add new controls. But when I remove and all controls are visible, vertical scroll is visible.
Some screenshots here:
Expected/correct scroll visibility:
Incorrect visibility:
Any ideas?
Update:
Here is some code
tableLayoutPanel1.SuspendLayout();
tableLayoutPanel1.RowCount = 0;
tableLayoutPanel1.RowStyles.Clear();
tableLayoutPanel1.AutoScroll = true;
tableLayoutPanel1.Padding = new Padding(0, 0, SystemInformation.VerticalScrollBarWidth, 0);
foreach (var item in objects)
{
tableLayoutPanel1.RowCount++;
tableLayoutPanel1.RowStyles.Add(new RowStyle(SizeType.AutoSize));
tableLayoutPanel1.Controls.Add(CreateNewItem(item));
}
tableLayoutPanel1.RowCount++;
tableLayoutPanel1.RowStyles.Add(new RowStyle(SizeType.AutoSize));
tableLayoutPanel1.Controls.Add(CreateAddButton());
tableLayoutPanel1.ResumeLayout();
and code for deleting
tableLayoutPanel1.SuspendLayout();
tableLayoutPanel1.Controls.Remove(item);
tableLayoutPanel1.RowStyles.RemoveAt(0);
tableLayoutPanel1.RowCount--;
tableLayoutPanel1.ResumeLayout();
AutoSize is true, AutoSizeMode is GrowAndShrink

The problem concerns TableLayoutPanel scrolling.
You have to use a Panel for scrolling instead of TableLayoutPanel.
Here is an example to solve this problem (for vertical scrolling) :
Set your TableLayoutPanel properties as follow :
Dock = DockStyle.Top
AutoSize = true
AutoSizeMode = AutoSizeMode.GrowAndShrink
AutoScroll = false.
Put your TableLayoutPanel into a Panel with properties :
Dock = DockStyle.Fill
AutoScroll = true
AutoSize = false.

when you remove the dynamic controls, you need to remove the extra rows that was inserted during the addition and re-size the table layout panel height to smaller than scroll container height.
During the addition the table layout panel height would have increased, which handled by the scroll container; but when you remove the controls, the table layout panel height doesn't reduce it's height to fit the scroll container.
One way to do this is to give fixed height to the rows and set the table layout panel seize set to "Auto".

One of the easiest and funniest solution is to just disable and enable tableLayoutPanel1.AutoScroll
In your Deleting procedure code add at the end these codes :
tableLayoutPanel1.AutoScroll = False
tableLayoutPanel1.AutoScroll = True

I inserted tableLayoutPanel to XtraScrollableControl(Devexpress control). tableLayoutPanel.Dock set to Top and XtraScrollableControl.Dock to Fill. This solution did not solves this problem, but I got behavior that I need.

I counted the number of rows in my TableLayoutPanel to see how many would fit. Below the amount that fit I set AutoScroll = false for the add and delete methods. The scroll will appear for large sets and disappear on small sets.
if (tableLayoutPanel.RowCount < 15)
{
panel1.AutoScroll = false;
}
else
{
panel1.AutoScroll = true;
}

I had a TableLayoutPanel on a UserControl, docked in Fill mode, with all rows on the TableLayoutPanel set to AutoSize. This UserControl would then dynamically get put on a panel, again in Fill mode, to show it to the user when needed. I put the UserControl on AutoScroll, but that alone did not solve it.
In the end, I solved it by going over all controls in the TableLayoutPanel, storing the extremities, and baking that into a Size to put in my UserControl's AutoScrollMinSize:
private void AdjustPanelSize(ScrollableControl panel, TableLayoutPanel tableLayoutPanel)
{
int maxX = 0;
int maxY = 0;
foreach (Control c in tableLayoutPanel.Controls)
{
maxX = Math.Max(maxX, c.Location.X + c.Width);
maxY = Math.Max(maxY, c.Location.Y + c.Height);
}
panel.AutoScrollMinSize = new Size(maxX, maxY);
}
This worked, and it also has the advantage that it can be called if there would ever be controls dynamically added or removed from the TableLayoutPanel.

Any idea why my usercontrol isn't centering in my tabcontrol?

I'm a little confused as to why this isn't working, since I had it working in a prototype and the only big difference I think is that I use a custom TabItem and UserControl instead of the default ones. I'm trying to get the usercontrol that appears to be centered in the tab window, but it seems to be aligned left.
You hand this method the usercontrol you want to use and it formats it and sticks it in the tabcontrol. In a test solution I did of this earlier, setting scroll's horizontal and vertical alignment to stretch fixed this, but it's not working in this case. Is there some other setting or something else somewhere that would override this?
public void CreateNewTab(UserControlGeneric new_user_control, string tab_header)
{
//TabItem tab = new TabItem();
TabItemIndexed tab = new TabItemIndexed();
//The scrollviewer is created/setup to make sure the usercontrol gets scroll bars if the window if ever made smaller than the usercontrol
ScrollViewer scroll = new ScrollViewer();
//How you programatically set a scrollviewer's height and width to be "Auto"
scroll.Height = Double.NaN;
scroll.Width = Double.NaN;
scroll.HorizontalScrollBarVisibility = ScrollBarVisibility.Auto;
scroll.VerticalScrollBarVisibility = ScrollBarVisibility.Auto;
scroll.HorizontalAlignment = System.Windows.HorizontalAlignment.Stretch;
scroll.VerticalAlignment = System.Windows.VerticalAlignment.Stretch;
scroll.Content = new_user_control;
tab.Content = scroll;
tab.Header = tab_header;
//If there aren't any tabs, then hide the "No Workspaces Open" notice (Since we're adding a tab)
if (!tabControl_main.HasItems) label_no_workspaces_open.Visibility = System.Windows.Visibility.Hidden;
tabControl_main.Items.Add(tab);
tabControl_main.SelectedItem = tab;
}

How to scroll in a fixed-size ToolStripDropDown

I am using a ToolStripDropDown control to implement the dropdown portion of a custom ComboBox-like control. In order to be visually appealing, I am imposing a MaximumSize on the dropdown and manually specifying the width of each ToolStripButton within it - the result is a popup which is the same width as the control that activates it, with a cap on the height of the height of the dropdown portion.
Example (simplified):
ToolStripDropDown dropDown = new ToolStripDropDown();
dropDown.MaximumSize = new Size(200, 100);
dropDown.RenderMode = ToolStripRenderMode.System;
dropDown.AutoSize = true;
for (int i = 0; i < 50; i++) {
ToolStripButton dropDownItem = (ToolStripButton)dropDown.Items.Add("Item " + i);
dropDownItem.AutoSize = false;
dropDownItem.Size = new Size(200, 20);
}
dropDown.Show(owningControl, new Point(0, owningControl.Height - 1));
As you can see, the constraints on the popup's size are applied, however the up/down scroll buttons are not displayed and there seems to be no way to make them appear. There do not appear to be any methods or properties within ToolStripDropDown regarding the scrolling offset or a mechanism to scroll a particular item into view (such as EnsureVisible() on ListViewItem).
How, then, can I get the dropdown to scroll? Any method would be sufficient, be it a scroll bar, scroll buttons or even the mouse-wheel.
(Incidentally, I have tried many times to make similar controls using a Form for the dropdown portion - despite trying dozens of solutions to prevent the popup from stealing focus or gaining focus when its controls are clicked, this seems to be a dead end. I have also ruled out using ToolStripControlHost, whose hosted control can still take focus away from the form that opened it.)

Finally cracked this one. It occurred to me that ContextMenuStrip and ToolStripDropDownMenu are capable of the auto-scrolling behaviour which their base class, ToolStripDropDown, cannot provide. Initially, I avoided these alternative controls because they usually add a wide margin. This can be removed via ShowImageMargin and ShowCheckMargin. Even after doing this, a small (approx 5px) margin remains. This can be removed by overriding the DefaultPadding property:
public class MyDropDown : ToolStripDropDownMenu {
protected override Padding DefaultPadding {
get { return Padding.Empty; }
}
public MyDropDown() {
ShowImageMargin = ShowCheckMargin = false;
RenderMode = ToolStripRenderMode.System;
MaximumSize = new Size(200, 150);
}
}
// adding items and calling Show() remains the same as in the question
This results in a popup window which can contain any type of ToolStrip item, enforces MaximumSize, has no margin and, most importantly, does not steal focus and cannot receive focus.

This is your nemesis:
internal virtual bool RequiresScrollButtons
{
get
{
return false;
}
set
{
}
}
It is internal, you cannot override it. You can revive your approach of using a Form by fixing the focus stealing behavior. Paste this into the form class:
protected override bool ShowWithoutActivation
{
get { return true; }
}