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Dynamically Adding Class of Controls

I am having trouble with dynamically adding a class of controls that should when working look like this:
When a new one is added it should appear in the left panel under the toolstrip.
So far I am having trouble making them appear (The one in the middle is just the design I made).
Here is the code:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
//Problem Occurs Here
EquationBox[] EquationBoxArray = new EquationBox[12];
for (int x = 0; x < 12; x++)
{
EquationBoxArray[x] = new EquationBox();
ActiveForm.Controls.Add(EquationBoxArray[x].mainPanel);
ActiveForm.Controls.Add(EquationBoxArray[x].colorPanel);
}
}
private void add_line_Click(object sender, EventArgs e) //Add Line
{
}
private void clear_Click(object sender, EventArgs e) //Clear Lines
{
}
}
public class EquationBox
{
public Panel colorPanel = new Panel();
public Panel mainPanel = new Panel();
public TextBox equationBox = new TextBox();
public CheckBox isVisibleBox = new CheckBox();
public EquationBox()
{
mainPanel.Size = new Size(200, 72);
colorPanel.Size = new Size(33, 72);
mainPanel.Location = new Point(50, 50);
colorPanel.Location = new Point(50, 50);
colorPanel.BackColor = Color.Red;
}
}
The problem occurs here:
//Problem Occurs Here
EquationBox[] EquationBoxArray = new EquationBox[12];
for (int x = 0; x < 12; x++)
{
EquationBoxArray[x] = new EquationBox();
ActiveForm.Controls.Add(EquationBoxArray[x].mainPanel);
ActiveForm.Controls.Add(EquationBoxArray[x].colorPanel);
}
When I run it, it return with:
Additional information: Cross-thread operation not valid: Control '' accessed from a thread other than the thread it was created on.
And even before that started happening, the EqautionBox wouldn't appear.
Thanks in advance, this is really troubling me.
For the constructor of EquationBox:
public EquationBox()
{
mainPanel.Size = new Size(200, 72);
colorPanel.Size = new Size(33, 72);
mainPanel.Location = new Point(50, 50);
colorPanel.Location = new Point(50, 50);
colorPanel.BackColor = Color.Red;
}

First, your control appeared, but mainPanel is overlap colorPanel and you can't see mainPanel (same BG color as your form), so swap which added first solved
EquationBox[] EquationBoxArray = new EquationBox[12];
for (int x = 0; x < 12; x++)
{
EquationBoxArray[x] = new EquationBox();
this.Controls.Add(EquationBoxArray[x].colorPanel);
this.Controls.Add(EquationBoxArray[x].mainPanel);
}
I am using this.Controls, not sure about the ActiveForm.Controls part, maybe on constructing, your Form1 is not the active one, so error occured.
Ps: I suggest add colorPanel to mainPanel, and only add mainPanel to Form. And UserControl is a good solution here as Steve Wellens said.

There are various issues with EquationBox the TextBox and CheckBox are not in the panel. It would be easier to make it a UserControl.
Then to do the positioning use a FlowLayoutPanel.

Adding dynamic controls to winform not working

I am creating dynamic PictureBox and label in WinForms. For this I have created a method which creates these items on the basis of given integer. In the first run while loading the form, its works smoothly, but when I pass any integer from a dropdown box, it does not make any changes. I tried debugging the code, and all the labels are created accordingly but it is not reflected in the winForm. I tried using Invalidate, Update, Refresh but non of them worked.
Here is the method that I have implemented.
private void createPictureBox(int size)
{
//this.Controls.Clear();
panel1.Controls.Clear();
Label[] ParameterLabel = new Label[size];
PictureBox[] ParameterBack = new PictureBox[size];
int y_value = 11;
this.Refresh();
for (int i = 0; i < size; ++i)
{
ParameterLabel[i] = new Label();
ParameterLabel[i].Text = "Test Text";
ParameterLabel[i].Font = new System.Drawing.Font("Calibri", 8, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((byte)(128)));
ParameterLabel[i].ForeColor = System.Drawing.Color.White;
ParameterLabel[i].BackColor = System.Drawing.Color.FromArgb(1, 0, 64);
ParameterLabel[i].Size = new System.Drawing.Size(145, 20);
ParameterLabel[i].Location = new Point(30, y_value);
ParameterLabel[i].Anchor = AnchorStyles.Left;
ParameterLabel[i].Visible = true;
ParameterBack[i] = new PictureBox();
ParameterBack[i].Image = Image.FromFile(STR_SETTING_PATH + "\\" + STR_IDEA_NO_XXXXX + "_01_nv.png");
ParameterBack[i].Size = new System.Drawing.Size(400, 32);
ParameterBack[i].Location = new Point(2, y_value - 10);
ParameterBack[i].Anchor = AnchorStyles.Left;
ParameterBack[i].Visible = true;
//this.Controls.Add(ParameterBack[i]);
y_value += 37;
}
panel1.Controls.AddRange(ParameterLabel);
panel1.Controls.AddRange(ParameterBack);
panel1.Invalidate();
}

Who can you distinguish between controls created in the first call and those created in other calls? I've tested your function with a tiny change, it seems to be working fine:
int CallIndex = 0; // this is on the form level
private void button1_Click(object sender, EventArgs e)
{
createPictureBox(3);
CallIndex += 1;
}
private void createPictureBox(int size)
{
// this has the exact same code as your method (copy-paste into my visual studio),
// except this change:
// ParameterLabel[i].Text = "Test Text";
ParameterLabel[i].Text = string.Format("Test {0}", CallIndex); // instead of the row above
}

I did remove the previously added controls and added the new one after which apparently solved my problem. The problem was due to piling of Controls one over another. I first removed the previously created controls using
this.Controls.Remove(UserControl1);
Then re-created its instance, which solved my problem.

Visual Studio-style undo drop-down button - custom ToolStripSplitButton

I'm looking to implement a Visual Studio-style undo drop-down button:
I've looked all over the internet, and can't seem to find any real implementations of this.
I've started by deriving from ToolStripSplitButton, but don't really know where to go from there. Its DropDown property is a ToolStripDropDown, but that doesn't seem to have anything regarding multiple items being selected, much less scrolling, and the text at the bottom.
So instead of the default ToolStripDropDown, I'm thinking maybe the whole drop down part should be a custom control, based on a combobox. The question then, is how to cause the right-side (drop down arrow) button to do something other than show its default drop down?
Am I on the right track here? Thanks!

Yes, I think you're on the right track. And in this case, ToolStripControlHost is your friend.
You don't necessarily need to derive from it (unless you are making your own control), but try just subscribing to the ToolStripSplitButton's DropDownOpening event:
Working example:
private ListBox listBox1;
public Form1()
{
InitializeComponent();
listBox1 = new ListBox();
listBox1.IntegralHeight = false;
listBox1.MinimumSize = new Size(120, 120); \\ <- important
listBox1.Items.Add("Item 1");
listBox1.Items.Add("Item 2");
}
private void toolStripSplitButton1_DropDownOpening(object sender, EventArgs e) {
ToolStripControlHost toolHost = new ToolStripControlHost(listBox1);
toolHost.Size = new Size(120, 120);
toolHost.Margin = new Padding(0);
ToolStripDropDown toolDrop = new ToolStripDropDown();
toolDrop.Padding = new Padding(0);
toolDrop.Items.Add(toolHost);
toolDrop.Show(this, new Point(toolStripSplitButton1.Bounds.Left,
toolStripSplitButton1.Bounds.Bottom));
}
Here is the result:
For your application, you would need to replace the ListBox with your own UserControl, so you can contain whatever your want in it. The ToolStripControlHost can only hold one control, and it's important to set the MinimumSize property, or else the dropped control isn't sized correctly.

Extra thanks to LarsTech! (I didn't know about ToolStripControlHost a few hours ago)
Here is my implementation, which is really close to the VS drop down...
You should be able to just drop this delegate & function into your Form:
public delegate void UndoRedoCallback(int count);
private void DrawDropDown(ToolStripSplitButton button, string action, IEnumerable<string> commands, UndoRedoCallback callback)
{
int width = 277;
int listHeight = 181;
int textHeight = 29;
Panel panel = new Panel()
{
Size = new Size(width, textHeight + listHeight),
Padding = new Padding(0),
Margin = new Padding(0),
BorderStyle = BorderStyle.FixedSingle,
};
Label label = new Label()
{
Size = new Size(width, textHeight),
Location = new Point(1, listHeight - 2),
TextAlign = ContentAlignment.MiddleCenter,
Text = String.Format("{0} 1 Action", action),
Padding = new Padding(0),
Margin = new Padding(0),
};
ListBox list = new ListBox()
{
Size = new Size(width, listHeight),
Location = new Point(1,1),
SelectionMode = SelectionMode.MultiSimple,
ScrollAlwaysVisible = true,
Padding = new Padding(0),
Margin = new Padding(0),
BorderStyle = BorderStyle.None,
Font = new Font(panel.Font.FontFamily, 9),
};
foreach (var item in commands) { list.Items.Add(item); }
if (list.Items.Count == 0) return;
list.SelectedIndex = 0;
ToolStripControlHost toolHost = new ToolStripControlHost(panel)
{
Size = panel.Size,
Margin = new Padding(0),
};
ToolStripDropDown toolDrop = new ToolStripDropDown()
{
Padding = new Padding(0),
};
toolDrop.Items.Add(toolHost);
panel.Controls.Add(list);
panel.Controls.Add(label);
toolDrop.Show(this, new Point(button.Bounds.Left + button.Owner.Left, button.Bounds.Bottom + button.Owner.Top));
// *Note: These will be "up values" that will exist beyond the scope of this function
int index = 1;
int lastIndex = 1;
list.Click += (sender, e) => { toolDrop.Close(); callback(index); };
list.MouseMove += (sender, e) =>
{
index = Math.Max(1, list.IndexFromPoint(e.Location) + 1);
if (lastIndex != index)
{
int topIndex = Math.Max(0, Math.Min(list.TopIndex + e.Delta, list.Items.Count - 1));
list.BeginUpdate();
list.ClearSelected();
for (int i = 0; i < index; ++i) { list.SelectedIndex = i; }
label.Text = String.Format("{0} {1} Action{2}", action, index, index == 1 ? "" : "s");
lastIndex = index;
list.EndUpdate();
list.TopIndex = topIndex;
}
};
list.Focus();
}
You can set it up and test like this, assuming you have a blank form (Form1) with a toolStrip that has 1 ToolStripSplitButton (toolStripSplitButton1) added:
public Form1()
{
InitializeComponent();
// Call DrawDropDown with:
// The clicked ToolStripSplitButton
// "Undo" as the action
// TestDropDown for the enumerable string source for the list box
// UndoCommands for the click callback
toolStripSplitButton1.DropDownOpening += (sender, e) => { DrawDropDown(
toolStripSplitButton1,
"Undo",
TestDropDown,
UndoCommands
); };
}
private IEnumerable<string> TestDropDown
{
// Provides a list of strings for testing the drop down
get { for (int i = 1; i < 1000; ++i) { yield return "test " + i; } }
}
private void UndoCommands(int count)
{
// Do something with the count when an action is clicked
Console.WriteLine("Undo: {0}", count);
}
Here is a better example using the Undo/Redo system from: http://www.codeproject.com/KB/cs/AutomatingUndoRedo.aspx
public Form1()
{
InitializeComponent();
// Call DrawDropDown with:
// The Undo ToolStripSplitButton button on the Standard tool strip
// "Undo" as the action name
// The list of UndoCommands from the UndoRedoManager
// The Undo method of the UndoRedoManager
m_TSSB_Standard_Undo.DropDownOpening += (sender, e) => { DrawDropDown(
m_TSSB_Standard_Undo,
"Undo",
UndoRedoManager.UndoCommands,
UndoRedoManager.Undo
); };
}
*Note: I did modify the Undo & Redo methods in the UndoRedoManager to accept a count:
// Based on code by Siarhei Arkhipenka (Sergey Arhipenko) (http://www.codeproject.com/KB/cs/AutomatingUndoRedo.aspx)
public static void Undo(int count)
{
AssertNoCommand();
if (CanUndo == false) return;
for (int i = 0; (i < count) && CanUndo; ++i)
{
Command command = history[currentPosition--];
foreach (IUndoRedo member in command.Keys)
{
member.OnUndo(command[member]);
}
}
OnCommandDone(CommandDoneType.Undo);
}

I'd suggest implementing the popup separately from the toolbar button. Popups are separate windows with a topmost-flag which auto-close when losing focus or pressing escape. If you code your own popup window that frees you from having to fit your behaviour to a preexisting model (which is going to be hard in your case). Just make a new topmost window with a listbox and status bar, then you are free to implement the selection behavior on the listbox like you need it.

Vs 2010 is a WPF application. If you are in the beginning of this application development than use WPF as a core technology. WPF drop down button is implemented in WPF ribbon. Source code is available on CodePlex.

Creating numerous PictureBoxes by code - only one is visible

I am trying to draw lots of instances of an image using the following code:
PictureBox[] sprites = new PictureBox[100];
private void Game_Load(object sender, EventArgs e)
{
PictureBox mainSprite = new PictureBox();
Bitmap img = new Bitmap(SpriteTest.Properties.Resources.Image); //Load a png image
mainSprite.Size = new Size(16, 16);
mainSprite.Image = img;
for(var i = 0; i < sprites.Length; i++)
{
sprites[i] = mainSprite;
//Keeping it simple for now with a single row of sprites
sprites[i].Location = new Point(i * 16, 8);
}
Game.ActiveForm.Controls.AddRange(sprites);
}
When it comes to running the code, only the last image is shown. While debugging the code, everything seems to be working as expected. I can also verify that the location is in fact being updated.
I have also tried adding the controls differently using the following code in the for loop (with no luck);
this.Controls.Add(sprites[i]);
I have had this problem many times, especially when I tried to create many GroupBoxes in a similar fashion. For the hours that I searched online as I tried to find a solution, nothing has ever fixed it.

You're only actually creating one instance of PictureBox:
PictureBox mainSprite = new PictureBox();
...
for(var i = 0; i < sprites.Length; i++)
{
sprites[i] = mainSprite;
Your array will have lots of reference to the same object. You should create a new PictureBox on each iteration of the loop:
for(var i = 0; i < sprites.Length; i++)
{
PictureBox mainSprite = new PictureBox();
mainSprite.Size = new Size(16, 16);
mainSprite.Image = img;
sprites[i] = mainSprite;
...
}

Dynamic creation of control

for (int i = 0; i < 200; i++)
{
Control control = new Control();
control = new CheckBox();
Size size = control.Size;
Point point = new Point(20, 22);
control.Location = point;
int width = size.Width + 5;
i += width;
list.Add(control);
}
foreach(Control c in list)
{
}
how do I create a new instance of checkbox? Because this way I am getting just one checkbox each time. I want to get three checkbox in each row.

Is this winforms? A first point: you don't need the new Control() each time (you simly discard it anyway when you new CheckBox(). How exactly do you want the layout to appear? Can you describe it a bit more please?
I imagine TableLayoutPanel might be a reasonable start...
[STAThread]
static void Main() {
Application.EnableVisualStyles();
Form form = new Form();
TableLayoutPanel layout = new TableLayoutPanel();
layout.Dock = DockStyle.Fill;
form.Controls.Add(layout);
layout.AutoScroll = true;
layout.ColumnCount = 3;
// size the columns (choice just to show options, not to be pretty)
layout.ColumnStyles.Add(new ColumnStyle(SizeType.Absolute, 200));
layout.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 50));
layout.ColumnStyles.Add(new ColumnStyle(SizeType.AutoSize));
layout.GrowStyle = TableLayoutPanelGrowStyle.AddRows;
for (int i = 0; i < 200; i++)
{
CheckBox chk = new CheckBox();
chk.Text = "item " + i;
layout.Controls.Add(chk);
}
Application.Run(form);
}
Otherwise, you'll need to manually set the Location (or Top and Left) of each; not simple.

Your code has problems. Let's work from sample code rather than a lesson. I'll create a Panel first, nice if you want to remove the checkboxes you created. You'd probably be interested in the user clicking a checkbox so lets add an event for that. Start a new WF project and drop a button on the form. Double click it, then paste this code:
private void button1_Click(object sender, EventArgs e) {
// Give the 3 checkboxes a decent spacing
int height = this.Font.Height * 3 / 2;
// Create the panel first, add it to the form
Panel pnl = new Panel();
pnl.Size = new Size(100, 3 * height);
pnl.Location = new Point(10, 5);
this.Controls.Add(pnl);
// Make three checkboxes now
for (int ix = 0; ix < 3; ++ix) {
CheckBox box = new CheckBox();
box.Size = new Size(100, height);
// As pointed out, avoid overlapping them
box.Location = new Point(0, ix * height);
box.Text = "Option #" + (ix + 1).ToString();
box.Tag = ix;
// We want to know when the user checked it
box.CheckedChanged += new EventHandler(box_CheckedChanged);
// The panel is the container
pnl.Controls.Add(box);
}
}
void box_CheckedChanged(object sender, EventArgs e) {
// "sender" tells you which checkbox was checked
CheckBox box = sender as CheckBox;
// I used the Tag property to store contextual info, just the index here
int index = (int)box.Tag;
// Do something more interesting here...
if (box.Checked) {
MessageBox.Show(string.Format("You checked option #{0}", index + 1));
}
}

It looks like you get your 200 instances, all placed at the same point.

Instantiate 3 new checkboxes inside your loop body, set their properties accordingly and add each of them to the list. After the code above is complete, you will have 600 checkboxes.
list.Add(Control1);
list.Add(Control2);
list.Add(Control3);

I am not sure about what you are trying to do, but I cleaned up your code a bit:
for (int i = 0; i < 200; i++)
{
Control control = new CheckBox();
control.Location = new Point(20, 22);
i += control.Size.Width + 5;
list.Add(control);
}
You should not add a new instance to the list if you want to add the control you just made.
Also:
Control control = new Control();
control = new CheckBox();
Is a bit redundant. Also to not get one control at the same spot multiple times you should alter the point. Hope this helps