Develop Reference

How to add a ListBox programmatically in a Form

I started out C# very recently and sorry if this question sounds dumb.
How do I add a Listbox in a Form that pops out from a Button click?
Note: The Form isn't the one that's added from the Solution Explorer whereby I can just drag a Listbox from the Toolbox to my Form.
So what I want is to create a ListBox in my file drawer1Form where I can add additional items. Thanks for the help in advance!:)
private void drawer1button_Click(object sender, EventArgs e) // Drawer 1 Button
{
drawer1Form df1 = new drawer1Form();
df1.StartPosition = FormStartPosition.CenterScreen;
df1.Show();
}
public partial class drawer1Form : Form // Creates drawer1Form
{
public drawer1Form()
{
Text = "Drawer 1 ";
}
}

Pretty much the same way as you'd do with any other object.
In the class of your form add a
private ListBox myAwesomeListBox;
Then in the button event handler add something like this:
myAwesomeListBox = new ListBox();
myAwesomeListBox.SuspendLayout();
// set all the properties that you want
myAwesomeListBox.Name = "myAwesomeListBox";
myAwesomeListBox.Location = new Point(...); // place it somewhere
myAwesomeListBox.Size = new Size(...); // give it a size
// etc...
df1.Controls.Add(myAwesomeListBox);
myAwesomeListBox.ResumeLayout();
This should be it.
I highly advise you to do it through the designer first though, and then take a look at the generated code in the form's .Designer.cs file, you'll have a very good understanding after reading through that.

ObjectListView editing doesn't work

I'm trying to create a simple listbox with ObjectListView (WinForm, C#). The goal is to have a single value (a double) and a check box.
I want to be able to edit the double value by Single Click, so here are the relevant lines of code from my MyWindow.Designer.cs file (i've left out the default values for efficiency):
this.olvDepths = new BrightIdeasSoftware.ObjectListView();
this.olvColumn1 = ((BrightIdeasSoftware.OLVColumn)(new BrightIdeasSoftware.OLVColumn()));
...
this.olvDepths.CellEditActivation = BrightIdeasSoftware.ObjectListView.CellEditActivateMode.SingleClick;
this.olvDepths.CheckBoxes = true;
this.olvDepths.CheckedAspectName = "IsDefault";
this.olvDepths.FullRowSelect = true;
//
// olvColumn1
//
this.olvColumn1.AspectName = "Depth";
this.olvColumn1.Text = "";
this.olvColumn1.IsEditable = true;
I then create a list of my class (ShieldingEntry) and use the olvDepths.SetObjects() with the list. My ShieldingEntry class looks like this:
public class ShieldingEntry
{
public double Depth { get; set; }
public bool IsDefault { get; set; }
}
However, when I click the field, it doesn't go into edit mode. I've also tried the DoubleClick, SingleClickAlways, and F2Only modes and they don't work either.
The Checkbox works fine.
************** I have additional information *********************
I've pulled and build the ObjectListView source, so I could step through it.
I put a breakpoint in the OLV StartCellEdit method and it gets called and appears to setup and select the control appropriately. It just never appears...
As I noted in the comments on the answer below, I've got this control on a tabbed dialog, and if I switch to another tab, then back, the control works fine.
What am I missing?

I've used ObjectListView before, and here is what I had to do:
Handle the CellEditStarting event. This event is raised when the cell goes into edit mode. Since OLV doesn't really have built-in editors, you have to make your own. Then handle the CellEditFinishing event to validate the data before putting it back into your model.
So first, handling the CellEditStarting event:
private void objlv_CellEditStarting(object sender, CellEditEventArgs e)
{
//e.Column.AspectName gives the model column name of the editing column
if (e.Column.AspectName == "DoubleValue")
{
NumericUpDown nud = new NumericUpDown();
nud.MinValue = 0.0;
nud.MaxValue = 1000.0;
nud.Value = (double)e.Value;
e.Control = nud;
}
}
This creates your editing control. If you want to make sure the size is right, you can set the size of the control (in this case a NumericUpDown) to the cell bounds using e.CellBounds from the event object.
This will show the editor when you click in the cell. Then you can handle the editor finished event to validate the data:
private void objlv_CellEditFinishing(object sender, CellEditEventArgs e)
{
if (e.Column.AspectName == "DoubleValue")
{
//Here you can verify data, if the data is wrong, call
if ((double)e.NewValue > 10000.0)
e.Cancel = true;
}
}
I don't think handling it is required, but its good practice to validate data from the user.
The editing control in the CellEditStarting event can be any control, even a user defined one. I've used a lot of user defined controls (like textboxes with browse buttons) in the cell editor.
[Edit]
I uploaded an example here dropbox link that seems to work. Might not be in the exact view as needed, but seems to do the job.

For anyone else with this problem. I had it specifically when trying to edit a 'null' value in a decimal? on the OLV on a tab page. Solution for me was to set UseCustomSelectionColors to 'False'. I didn't look elsewhere to see if it was reported as a bug. Seems like a bug.

Winforms Control Layout at Runtime

I've been working on developing a custom control which will be used in our CRM frontend. The control itself is nothing special, it simply wraps two labels, text edits, and a button into a single control. (The control is only acting as a wrapper, a bit long winded, but unfortunately our only option due to various restrictions)
I though it would be nice to give the control a Font and ForeColor property, that would change the Font and Color of the labels. Changing the font size means that the relative position of the text boxes be changed to keep everything in line. No problem.
I encapsulated the layout logic in an UpdateLayout method, which is called on the set accessor of the Font property and everything works beautifully at design time, however, at runtime, the Font of the labels is correct, but the layout of the text boxes and button are still in the default positions, hence, the labels overlap.
What am I missing in for updating the position of controls at the init stage in runtime? I've tried calling the UpdateLayout() method from both Initialize and the constructor of the control, alas to no avail.
Am i missing something obvious here?
EDIT:
As requested, I whipped up a quick test. My test control looks like so (Not including Designer code):
public partial class TestControl : UserControl
{
private Font _font;
[Browsable(true)]
public override Font Font
{
get
{
return this._font ?? SystemFonts.DefaultFont;
}
set
{
this._font = value;
this.DoLayout();
}
}
private void DoLayout()
{
this.label1.Font = this._font;
this.Size = new Size(label1.Width + textBox1.Width + 10,
label1.Height >= textBox1.Height ? label1.Height : textBox1.Height);
this.textBox1.Location = new Point(label1.Location.X + 5 + label1.Width, 1);
this.Update();
}
public TestControl()
{
InitializeComponent();
}
protected override void OnLayout(LayoutEventArgs e)
{
base.OnLayout(e);
DoLayout();
}
}
That works great at design time, but runtime, less so...
EDIT2:
So the above code doesn't entirely reflect the problem accurately, however, I have tried Jogy's suggestion of overriding the OnLayout method, and lo and behold, it works!
I'm relatively new to Custom Controls, so a rookie mistake on my part. This will definitely be committed to the long term memory.

Override OnLayout() method and call your UpdateLayout() there.

Thanks for supplying the code, I would provide the properties by reusing already available controls.
public override Font Font
{
get { return this.label1.Font; }
set
{
this.label1.Font = value;
// Additional code to update related controls.
}
}
Also be aware that the declaration of
private Font _font;
Delivers a non-initialized variable, and by using it in the "Do_Layout" might use a null value. Maybe change it to the following when using your code.
this.label1.Font = this.Font;

C# VSTO - dynamically set RibbonControl

I have a customized Ribbon in Word. The Ribbon has one comboBox: comboBox_recentConditions which was defined using the Designer - so it's initalized and is empty at load. Now, I would like to dynamically set this comboBox each time the Application_WindowActivate event is fired.
Each Word document has its own instance of class called RibbonControls:
class RibbonControls
{
private RibbonComboBox recentConditionComboBox;
public RibbonControls()
{
this.recentConditionComboBox = new RibbonComboBox();
}
public RibbonComboBox RecentConditionComboBox
{
get
{
return recentConditionComboBox;
}
set
{
recentConditionComboBox = value;
}
}
}
Now in Application_WindowActivate event i do the following:
static void Application_WindowActivate(Document doc, Window Wn)
{
Globals.Ribbons.SourceRibbon.comboBox_recentConditions = WordGate.docRibbonControls.RecentConditionComboBox;
}
The problem is that the Ribbon comboBox control doesn't changes, it's always empty, even after Application_WindowActivate is called.
I tested at run-time to see if each document indeed has its own comboBox with its items - which seems to work.
What am I missing?
To clear my question:
Let's say I have 3 items in the comboBox.Items. When clicking on it I see nothing, but if I add this:
MessageBox.Show(Globals.Ribbons.SourceRibbon.comboBox_recentConditions.Items.Count.ToString());
at the end of Application_WindowActivate it will print the number 3.
Thanks.

You cant do it that way. Please have a read on Ribbon callbacks
You have to use the getItemLabel event which will add items to combo box. If you want to load the combobox during WindowActivate then call Ribbon.Invalidate or Ribbon.InvalidateControl which will call all relevant ribbon callbacks.

Populate from a child form to an another childform

In my project, I have a mdi container mdiMother whith two childform (mdiChild1 and mdiChild2). The mdiChild1 have a listview (mode view detail). The mdiChild2 have a button who goal to populate the listview in mdiChild1.
I have done some peace of code. I copy this code into the mdiChild1, create a button, try it and it s works (mean: I see the listview populate).
My problem:
When I press button from mdiChild2, my listview isn't populate with same code in mdiChild1 the code do the job.

You must control child's controls from mdiMother.
Create static instance from each mdiChild, after that when you want to call method from each of them you must use from these static instances.
Like this:
public class mdiMother{
public static mdiChild1 ch1;
public static mdiChild2 ch2;
public mdiMother(){
ch1 = new mdiChild1();
ch2 = new mdiChild2();
}
}
public class mdiChild1{
public void Do(){
// fill list
}
}
public class mdiChild2{
public void CallMdiChild1(){
mdiMother.ch1.Do();
}
}

Thank to all. I solve my problem and I see it was so stupid. Tha way it's didn't populate: dont refere to the good form. For doing the job, i make a ref to the active mdi child ... and it's work :)
Thanx all for your help... and many thanx to Ahmad who's giving to me the good way to find the solve :p