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How to make correct initialization of ComboBox?

I need show droppeddown combobox after start program.
I need in dropdown style only, not simple style.
This is simple fragment of my program:
private void Form1_Shown(object sender, EventArgs e)
{
CB1.Items.Add("1");
CB1.DropDownStyle = ComboBoxStyle.DropDown;
CB1.DroppedDown = true;
}
But I found the watch sign as cursor till I click on Form in any place.
I guessed that my Form have not fully active state and wait for something.
When I click Form (or combobox or any control) by LBM, it activated fully and all works fine.
Of course the combobox is dropup then, so I need click combobox twice.
Еell me please what is correct initialization of such style combobox without "Cursor = Cursors.Default;"

You can simply wait until cursor is the default:
while (Cursor.Current != Cursors.Default)
{
Application.DoEvents();
}
CB1.Items.Add("1");
CB1.DropDownStyle = ComboBoxStyle.DropDown;
CB1.DroppedDown = true;
Application.DoEvents simply process messages from the window queue, so you can process message until you get that cursor is the default. In that moment, you can drop down your control without problem.
If you prefer, create a extension method for the Form:
public static class FormExtends
{
public static void WaitToDefaultCursor(this Form form)
{
while (Cursor.Current != Cursors.Default)
{
Application.DoEvents();
}
}
}
And use it:
this.WaitToDefaultCursor();
CB1.Items.Add("1");
CB1.DropDownStyle = ComboBoxStyle.DropDown;
CB1.DroppedDown = true;
NOTE: I use Cursor.Default but not to change the cursor. The form is processing messages and it's difficult to select a good moment to drop down the control.

In the WinForms DevExpress XtraWizard control, how can one hide the back button?

I know that if I set the WizardStyle of an XtraWizard control to WizardAero, it will remove or hide the back button from the first page instead of simply disabling it, as can be seen here. I want the same behaviour, but I want to keep the WizardStyle as Wizard97.
Is this possible, and if so, how?

One way to do this would be to use the CustomizeCommandButtons event on the WizardControl.
private void wizardControl1_CustomizeCommandButtons(object sender, CustomizeCommandButtonsEventArgs e)
{
e.PrevButton.Visible = false;
}
If you only want to hide it on the first page
private void wizardControl1_CustomizeCommandButtons(object sender, CustomizeCommandButtonsEventArgs e)
{
if(wizardControl1.SelectedPageIndex == 0)
e.PrevButton.Visible = false;
}
It seems like it will reset the visibility each time (so you don't need to toggle it back on). Anyway, I think this is what you're looking for.
http://documentation.devexpress.com/#WindowsForms/DevExpressXtraWizardWizardControl_CustomizeCommandButtonstopic

You can also set your own fields to the wizard buttons and then use these anywhere in your code. This will, for example, allow you to hide/disable the "Next" button until all fields page have been completed.
private void NodeConfigurationWizardCustomizeCommandButtons(object sender, CustomizeCommandButtonsEventArgs e)
{
_nextButton = e.NextButton;}
private void GetRowsButtonClick(object sender, EventArgs e)
{
var rowList = ServiceClient.GetAvailableRows();
var rowsReturned = rowList.Count > 0;
_nextButton.Button.Enabled = rowsReturned ;}

c# checkbox problem

I want to minimize the amount of code i have to write for this small problem. I have 1 textbox that has a relationship with 2 checkboxes as yes and no. The textbox on form load is set to disabled. When the yes checkbox is changed this event occurs -
private void checkYes1_CheckedChanged(object sender, EventArgs e)
{
textBox14.Enabled = true;
checkNo1_cbx.Checked = false;
}
and when the no checkbox is changed -
private void checkNo1_cbx_CheckedChanged(object sender, EventArgs e)
{
textBox14.Enabled = false;
checkYes1_cbx.Checked = false;
}
Although another problem is that i have to press yes twice to get it to check.
This is for a question on a form and so far it goes up to 11 questions and more will be added in the future. So my 2 problems so far is -
How can I fix the problem when the checkbox is changed I have to press it again to check it.
Is it possible to improve this code to minimize the amount of code i will have to write in the future.

private void checkYes1_CheckedChanged(object sender, EventArgs e)
{
OnCheck(true);
}
private void checkNo1_cbx_CheckedChanged(object sender, EventArgs e)
{
OnCheck(false);
}
private void OnCheck(bool yes)
{
textBox14.Enabled = yes;
checkNo1_cbx.CheckedChanged -= checkNo1_cbx_CheckedChanged;
checkNo2_cbx.CheckedChanged -= checkYes1_CheckedChanged;
checkNo1_cbx.Checked = !yes;
checkNo2_cbx.Checked = yes;
checkNo1_cbx.CheckedChanged += checkNo1_cbx_CheckedChanged;
checkNo2_cbx.CheckedChanged += checkYes1_CheckedChanged;
}
However consider using RadioBox instead of CheckBox because you want to if one being checked uncheck the other..
Edit: In your previous design, you get it wrong changed I have to press it again to check it because of you have two event handlers assigned to each of the check boxes. now at your code when the first one checked, you are disable the text box and make the other unchecked, but when you call the other unchecked Checked = false you are calling the second check box event handler also so it will enable the text and make the first one disable... you should remove the event handler by -= when updating at your code if you don't want the handler handler to be triggered again.. And that what I am doing in the code sample provided.

Why are you using 2 checkoboxes ? One checkbox (check1) would be enough:
private void check1_CheckedChanged(object sender, EventArgs e)
{
textBox14.Enabled = check1.Checked;
}
EDIT:
Assuming that each question mean 1 textbox, then you need 1 checkbox per textbox... this could be further improved by using a more complex approach

unless there is a reason that you are making a round trip back and forth to the server to disabled a textbox on a checkbox selection change, why don't you just do that all on the client side via javascript?

I agree with Yahia. If you do need to explicitly provide the two options though, then you should consider using RadioButtons.

Hanging controls properties on Application.Idle, good or bad?

I'm writing a simple application with several controls on a Windows form. I need to monitor the state of buttons (enabled/disabled) according to the state of a textbox and a listbox.
For example, when the listbox is empty, buttons Delete, Delete All and Edit are to be disabled, or when either the textbox or the listbox is empty button Forward is disabled, and so on.
So, I put the change of these properties on Application.Idle event, so it goes something like this:
private void MainForm_Load(object sender, EventArgs e)
{
Application.Idle += new EventHandler(Application_Idle);
}
public void Application_Idle(object sender, EventArgs e)
{
CheckFillingFields(forwardBtn);
CheckFillingList(deleteBtn);
CheckFillingList(deleteAllBtn);
CheckFillingList(editBtn);
}
private void CheckFillingFields(object sender)
{
if (questionTxt.Text == "" || answersLst.Items.Count == 0)
(sender as Button).Enabled = false;
else
(sender as Button).Enabled = true;
}
private void CheckFillingList(object sender)
{
if (answersLst.Items.Count == 0)
(sender as Button).Enabled = false;
else
(sender as Button).Enabled = true;
}
So, the question is - is it acceptable to use Application.Idle in this case? Or should I make these properties dependable on user actions? (For example, when the user deletes an item from the listbox, I should check if it was the last one, and disable the corresponding buttons.)
Thanks a lot in advance, I really appreciate your help!

The simple answer is that, yes, the idle checking is bad and you should re-check the state of your controls on their change events, not "whenever possible".

ToggleButton in C# WinForms

Is it possible to create a toggle button in C# WinForms? I know that you can use a CheckBox control and set it's Appearance property to "Button", but it doesn't look right. I want it to appear sunken, not flat, when pressed. Any thoughts?

You can just use a CheckBox and set its appearance to Button:
CheckBox checkBox = new System.Windows.Forms.CheckBox();
checkBox.Appearance = System.Windows.Forms.Appearance.Button;

Check FlatStyle property. Setting it to "System" makes the checkbox sunken in my environment.

You may also consider the ToolStripButton control if you don't mind hosting it in a ToolStripContainer. I think it can natively support pressed and unpressed states.

thers is a simple way to create toggle button. I test it in vs2010. It's perfect.
ToolStripButton has a "Checked" property and a "CheckOnClik" property. You can use it to act as a toggle button
tbtnCross.CheckOnClick = true;
OR
tbtnCross.CheckOnClick = false;
tbtnCross.Click += new EventHandler(tbtnCross_Click);
.....
void tbtnCross_Click(object sender, EventArgs e)
{
ToolStripButton target = sender as ToolStripButton;
target.Checked = !target.Checked;
}
also, You can create toggle button list like this:
private void Form1_Load(object sender, EventArgs e)
{
arrToolView[0] = tbtnCross;
arrToolView[1] = tbtnLongtitude;
arrToolView[2] = tbtnTerrain;
arrToolView[3] = tbtnResult;
for (int i = 0; i<arrToolView.Length; i++)
{
arrToolView[i].CheckOnClick = false;
arrToolView[i].Click += new EventHandler(tbtnView_Click);
}
InitTree();
}
void tbtnView_Click(object sender, EventArgs e)
{
ToolStripButton target = sender as ToolStripButton;
if (target.Checked) return;
foreach (ToolStripButton btn in arrToolView)
{
btn.Checked = false;
//btn.CheckState = CheckState.Unchecked;
}
target.Checked = true;
target.CheckState = CheckState.Checked;
}

How about this?
Assuming you have System.Windows.Forms referenced.
var cbtnToggler = new CheckBox();
cbtnToggler.Appearance = Appearance.Button;
cbtnToggler.TextAlign = ContentAlignment.MiddleCenter;
cbtnToggler.MinimumSize = new Size(75, 25); //To prevent shrinkage!
Hope this helps ;)

This is my simple codes I hope it can help you
private void button2_Click(object sender, EventArgs e)
{
if (button2.Text == "ON")
{
panel_light.BackColor = Color.Yellow; //symbolizes light turned on
button2.Text = "OFF";
}
else if (button2.Text == "OFF")
{
panel_light.BackColor = Color.Black; //symbolizes light turned off
button2.Text = "ON";
}
}

When my button's FlatStyle is set to system, it looks flat. And when it's set to popup, it only pops up when mouses over. Either is what I want. I want it to look sunken when checked and raised when unchecked and no change while mousing over (the button is really a checkbox but the checkbox's appearance property is set to button).
I end up setting the FlatStyle to flat and wrote a new Paint event handler.
private void checkbox_paint(object sender, PaintEventArgs e)
{
CheckBox myCheckbox = (CheckBox)sender;
Rectangle borderRectangle = myCheckbox.ClientRectangle;
if (myCheckbox.Checked)
{
ControlPaint.DrawBorder3D(e.Graphics, borderRectangle,
Border3DStyle.Sunken);
}
else
{
ControlPaint.DrawBorder3D(e.Graphics, borderRectangle,
Border3DStyle.Raised);
}
}
I give a similar answer to this question:
C# winforms button with solid border, like 3d
Sorry for double posting.

You can always code your own button with custom graphics and a PictureBox, though it won't necessarily match the Windows theme of your users.

I ended up overriding the OnPaint and OnBackgroundPaint events and manually drawing the button exactly like I need it. It worked pretty well.

use if command to check status and let operate as a toggle button
private void Protection_ON_OFF_Button_Click(object sender, EventArgs e)
{
if (FolderAddButton.Enabled == true)
{
FolderAddButton.Enabled = false;
}
else
{
FolderAddButton.Enabled = true;
}
}

You should look into Siticone I use it and I love it. It works exactly like a checkbox but is a toggle button. Its downside is a message box will come up every time you open Visual Studios so I just installed a tool that disables it. You can also look into Guana but I found that to have a few bugs :)

Changing a CheckBox appearance to Button will give you difficulty in adjustments. You cannot change its dimensions because its size depends on the size of your text or image.
You can try this: (initialize the count variable first to 1 | int count = 1)
private void settingsBtn_Click(object sender, EventArgs e)
{
count++;
if (count % 2 == 0)
{
settingsPanel.Show();
}
else
{
settingsPanel.Hide();
}
}
It's very simple but it works.
Warning: This will work well with buttons that are occasionally used (i.e. settings), the value of count in int/long may be overloaded when used more than it's capacity without closing the app's process. (Check data type ranges: http://msdn.microsoft.com/en-us/library/s3f49ktz.aspx)
The Good News: If you're running an app that is not intended for use 24/7 all-year round, I think this is helpful. Important thing is that when the app's process ended and you run it again, the count will reset to 1.