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Why does the ListView refuse to display its columns, items, and subitems (shows only Group)?

The ListView seems to be as cantankerous as a polecat and as temperamental as a [elided by the P.C. police]
With help from - and others, I was able to get a ListView working just as I wanted
it to
(http://stackoverflow.com/questions/11423537/how-to-add-subitems-to-a-listview).
Now I'm converting that simple demo for use in a real app.
I create the columns in the form's Load event:
listViewGroupsItems.Columns.Add(colHeadName);
listViewGroupsItems.Columns.Add(colHeadRate);
...but they don't display. However, there is a blank line above my first item. So why are no text values being displayed. Are they "there" but invisible? Why would they get wiped out?
Anyway, what I want to see is:
column1Title column2Title
Group1Name
Item subitem
Item subitem
Group2Name
Item subitem
Group1Name
Item subitem
Item subitem
Item subitem
Item subitem
...but what I actually see is just:
[blank line]
Group1Name
...that's it!
The ListView's View property is set to Details; otherwise, all of the properties are the default values.
My listview code is:
private void AddGroupsAndItems() {
Dictionary<string, string> GroupsDict = PlatypusData.GetGroupsForTopLevel(Convert.ToInt32(labelTopLevel.Tag));
int currentGroup = 0;
foreach (KeyValuePair<string, string> entry in GroupsDict) {
string GroupNumber = entry.Key;
string GroupName = entry.Value;
listViewGroupsItems.Groups.Add(new ListViewGroup(GroupName, HorizontalAlignment.Left));
Dictionary<string, string> ItemsDict = PlatypusData.GetItemsForGroup(GroupNumber);
foreach (KeyValuePair<string, string> itemEntry in ItemsDict) {
string itemID = itemEntry.Key;
string itemName = itemEntry.Value;
ListViewItem lvi = new ListViewItem(string.Format("{0} ({1})", itemName, itemID));
lvi.SubItems.Add(PlatypusData.GetDuckbillNameForItemId(itemID));
listViewGroupsItems.Items.Add(lvi);
listViewGroupsItems.Groups[currentGroup].Items.Add(lvi);
}
currentGroup++;
}
}
UPDATE
I changed my code in the form's Load event from:
var colHeadName = new ColumnHeader { Text = Resources.RateRequestForm_RateRequestForm_Load_Billing_Account_Client, Width = 160 };
var colHeadRate = new ColumnHeader { Text = Resources.RateRequestForm_RateRequestForm_Load_RatePlan_ID, Width = 120 };
listViewCustomerBillAccountsClients.Columns.Add(colheadName); //colHeadName);
listViewCustomerBillAccountsClients.Columns.Add(colheadRate); //colHeadRate);
...to:
ColumnHeader colheadName = new ColumnHeader();
ColumnHeader colheadRate = new ColumnHeader();
listViewCustomerBillAccountsClients.Columns.Add(colheadName);
listViewCustomerBillAccountsClients.Columns.Add(colheadRate);
...and it made no difference at all.
It would seem that the ColumnHeader constructor should be able to take a string of what it should display, but even when I do that:
ColumnHeader colheadName = new ColumnHeader("This");
ColumnHeader colheadRate = new ColumnHeader("That");
...there is still no change (according to Intellisense or whatever it's called, the string arg is an ImageKey, but I thought I'd try just out of thoroughness/frustration.

Late to the party, but I've just spent some time trying to solve a similar problem. The answer I found was that when clearing the list before filling, you must use
listviewGroupItems.Items.Clear();
not
listviewGroupItems.Clear();
The ListView.Clear() method clears everything from the control--including the columns

I had the same issue today. I had coded listView.Clear() as user2867342 mentioned. I needed to change that to listView.Items.Clear(), but that did not make the columns appear. The columns were there, and I could click on them and resize them, but they were completely blank.
I had a ListView set to Details mode. I also had set the OwnerDraw property to true, because I wanted to paint my own progress bar column. MSDN says the following about the OwnerDraw property (emphasis mine):
A ListView control is normally drawn by the operating system. In order
to customize the appearance of ListView items, subitems, and column
headers, set the OwnerDraw property to true and provide a handler for
one or more of the following events: DrawItem, DrawSubItem,
DrawColumnHeader. This is called owner drawing. When the View property
is set to View.Details, all three events occur; otherwise, only the
DrawItem event occurs.
I had to implement the DrawColumnHeader event. In my case, the defualt worked fine, so the method sets the DrawDefault event parameter to true. After implementing this event handler, the column headers appeared correctly:
...Windows.Forms designer code...
listView.DrawColumnHeader += new DrawListViewColumnHeaderEventHandler(this.listView_DrawColumnHeader);
...
private void listView_DrawColumnHeader(object sender, DrawListViewColumnHeaderEventArgs e)
{
e.DrawDefault = true;
}

You're missing column headers in your code. (fixed)
Per the MSDN:
"If your ListView control does not have any column headers specified and you set the View property to View.Details, the ListView control will not display any items. If your ListView control does not have any column headers specified and you set the View property to View.Tile, the ListView control will not display any subitems."
Granted, you'll probably need to make more adjustments than what you see in my SS, but it at least answers your question as to why you are getting blanks.
Edit (Changed lines, although changing them back to your code didn't skew my successful results):
lvi.Group = listViewGroupsItems.Groups[currentGroup];
listViewGroupsItems.Items.Add(lvi);

One more thing to check I just found:
OwnerDraw must be false.
Copy & Paste from previous project and forgot that I used OwnerDraw

Overriding OnDoubleClick() event on a List View

I have a MyListView class that is inheriting from ListView, and is overriding OnDragDrop() (and the other necessary events to implement drag and drop). When I place two of these MyListviews on a form I am able to drag an item from one of them and drop it to the other one. This part works.
Now I want to override OnDoubleClick() to that class such that again if I place two of these MyListViews on a form and double clicked on one of them, the item gets removed from that and gets added to the other one. But I can't get my head around how to do this one.
Could you please give me some ideas? Thanks.

Don't know if you manage the sleection of the item in a particular way, but you can
or after handling double-click look for SelectedItems and act on it
or you can add a code like this using ListViewHitTestInfo class:
private override OnDoubleClick(...)
{
ListViewHitTestInfo hit = this.HitTest(e.Location);
if (hit.Item != null)
{
ListViewItem doubleClickedItem = hit.Item;
}
}

Put the logic in your host form by:
Handle double-click of first ListView
Remove from first ListView
Add to second ListView
Unless you are doing this in many different forms - it's not worth complicating it more than that.
EDIT:
If justified, centralizing can be as easy as adding a method which does the same thing (pseudocode)
public void MyForm_OnListViewDoubleClick(object sender, EventArgs e)
{
MoveListItem(firstListView, secondListView);
}
// ...
public static void MoveListItem(ListView source, ListView destination)
{
var listItem = source.SelectedItem;
source.Remove( listItem );
destination.Add( listItem );
}

Here's the answer to your title
protected override void OnDoubleClick(EventArgs e)
{
base.OnDoubleClick(e);
}
And here is the answer to your question
Using DoubleClick event on a inherited class from ListView
This just links back to your other, very similar question.

How to disable a checkbox in a checkedlistbox?

I have some items in a CheckedListBox, I want to disable the CheckBox of first item in it.
i.e. I want to disable the first item in the CheckedListBox, because I want to tell the user visually that option is not available.

Combining 2 of the above partial answers worked great for me.
Add your items to the list with:
myCheckedListBox.Items.Add(myItem, myState);
Where myState is CheckState.Indeterminate for items that should be disabled.
Then add an event handler to keep those items from being changed:
myCheckedListBox.ItemCheck += (s, e) => { if (e.CurrentValue == CheckState.Indeterminate) e.NewValue = CheckState.Indeterminate; };
This does not allow you to use 'Indeterminate' in this list for its normal purpose but it does give a look very similar to what one would expect for a disabled item and it provides the correct behavior!

Though this post is pretty old, the last added answer has been submitted in April this year,
and I hope this will help someone.
I was after something similar : a checked list box that behaves like
a lot of installers, which offer a list of options where some features are required and
thus are both checked and disabled.
Thanks to this post (Can I use a DrawItem event handler with a CheckedListBox?)
I managed to do that, subclassing a CheckedListBox control.
As the OP in the linked post states, in the CheckedListBox control the OnDrawItem event is never fired,
so subclassing is necessary.
It's very basic, but it works.
This is what it looks like (the CheckBox above is for comparison) :
NOTE: the disabled item is really disabled : clicking on it has no effects whatsoever (as far as I can tell).
And this is the code :
public class CheckedListBoxDisabledItems : CheckedListBox {
private List<string> _checkedAndDisabledItems = new List<string>();
private List<int> _checkedAndDisabledIndexes = new List<int>();
public void CheckAndDisable(string item) {
_checkedAndDisabledItems.Add(item);
this.Refresh();
}
public void CheckAndDisable(int index) {
_checkedAndDisabledIndexes.Add(index);
this.Refresh();
}
protected override void OnDrawItem(DrawItemEventArgs e) {
string s = Items[e.Index].ToString();
if (_checkedAndDisabledItems.Contains(s) || _checkedAndDisabledIndexes.Contains(e.Index)) {
System.Windows.Forms.VisualStyles.CheckBoxState state = System.Windows.Forms.VisualStyles.CheckBoxState.CheckedDisabled;
Size glyphSize = CheckBoxRenderer.GetGlyphSize(e.Graphics, state);
CheckBoxRenderer.DrawCheckBox(
e.Graphics,
new Point(e.Bounds.X + 1, e.Bounds.Y + 1), // add one pixel to align the check gliph properly
new Rectangle(
new Point(e.Bounds.X + glyphSize.Width + 3, e.Bounds.Y), // add three pixels to align text properly
new Size(e.Bounds.Width - glyphSize.Width, e.Bounds.Height)),
s,
this.Font,
TextFormatFlags.Left, // text is centered by default
false,
state);
}
else {
base.OnDrawItem(e);
}
}
public void ClearDisabledItems() {
_checkedAndDisabledIndexes.Clear();
_checkedAndDisabledItems.Clear();
this.Refresh();
}
}
Use it like this:
checkedListBox.Items.Add("Larry");
checkedListBox.Items.Add("Curly");
checkedListBox.Items.Add("Moe");
// these lines are equivalent
checkedListBox.CheckAndDisable("Larry");
checkedListBox.CheckAndDisable(0);
Hope this can help someone.

Disabling items isn't a great idea, the user will have no good feedback that click the check box won't have any effect. You cannot use custom drawing to make it obvious. Best thing to do is to simply omit the item.
You can however easily defeat the user with the ItemCheck event:
private void checkedListBox1_ItemCheck(object sender, ItemCheckEventArgs e) {
if (e.Index == 0) e.NewValue = e.CurrentValue;
}

To disable any particular item use following:
checkedListBox1.SetItemCheckState(0, CheckState.Indeterminate);
SetItemCheckState takes index of item and CheckState Enum
Indeterminate is used to show shaded appearance

I know it has been a while, but I found this in my search for a list box and thought I would add it to the discussion.
If you have a listbox and want to disable all of the checkboxes so they cannot be clicked, but not disable the control so the user can still scroll etc. you can do this:
listbox.SelectionMode = SelectionMode.None

The CheckedListBox will not work in this way. CheckedListBox.Items is a collection of strings so they cannot be "disabled" as such.
Here are some discussions about possible solutions that might help you: here and here.

This works for me:
checkedListBox1.SelectionMode = SelectionMode.None;
Which means no items can be selected
None: No items can be selected.
For more info, you can check it here: SelectionMode Enumeration.

The solution is to use the event ItemChecking:
_myCheckedListBox.ItemChecking += (s, e) => e.Cancel = true;
This will cancel all the checking on every item, but you can always do more refined solution but testing the current .SelectedItem

Here's how I did it in a helpdesk application I wrote:
First, I made it so the check box was greyed out as I added it to the list during form load:
private void frmMain_Load(object sender, EventArgs e)
{
List<string> grpList = new List<string>();
ADSI objADSI = new ADSI();
grpList = objADSI.fetchGroups();
foreach (string group in grpList)
{
if (group == "SpecificGroupName")
{
chkLst.Items.Add(group, CheckState.Indeterminate);
}
else
{
chkLst.Items.Add(group);
}
}
Then I used an event so that when clicked it ensures it stays clicked:
private void chkLst_SelectedIndexChanged(object sender, EventArgs e)
{
if (chkLst.SelectedItem.ToString() == "SpecificGroupName")
{
chkLst.SetItemCheckState(chkLst.SelectedIndex, CheckState.Indeterminate);
}
}
The idea here is that on my form it's set so that the box checks on item click/select. This way I could kill two birds with one stone. I could keep this event from causing problems when the item is first checked and added during form load. Plus making it check on select allows me to use this event instead of the item checked event. Ultimately the idea is to keep it from messing up during the load.
You'll also notice that it doesn't matter what the index number is, that variable is unknown because in my app it's grabbing a list of groups from AD that exist in a specific OU.
As to whether this is a good idea or not, that's dependent on the situation. I have another app where the item to disable is dependent on another setting. In this app I just want the helpdesk to see that this group is required so they don't go removing them from it.

Try Below Code:
Private Sub CheckedListBox1_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles CheckedListBox1.MouseUp
If (Condition) Then
Me.CheckedListBox1.SelectedIndex = -1
End If
End Sub

I think an alternative solution, is using Telerik components.
A RadListControl can give you that option:

Click a custom control and show some variables related to it in another control

in my Win Forms app I create an array of dynamic custom controls inside a loop. These, lets call them 'boxes', are like my basic pieces of information. I also create string arrays in other parts of the code that contain the information of this 'boxes', so that for example string[3] is a variable of box[3] and so does stringa[3], stringb[3], stringc[3]... all the arrays with the same index are related to the box with that index. Hope I make myself clear.
Only 2 of this strings are shown in 2 labels inside each custom control 'box' in the array, but the others are there because I want to make something so that when the user clicks one of these controls the other strings can be shown in another control. Sort of something like "More Information...". All the 'boxes' in the array need to have the same event handler because I create +100.
To put it more into context, each custom control 'box' in the array shows the Symbol and the Price of a stock and I want that when the user clicks on each stock more quote information is shown on another special control which is like a placeholder for "More info".
I am thinking of 2 ways to do it:
If I could "detect" the index of the clicked control (which is the same in the strings related to it), I could just set this to an int j and all I have to do is show all the strings a,b,c... with index j. Unfortunately I cannot find a way to do this, maybe it is not even possible.
The other way I have thought is to create some properties for my custom control which "store" this variables, and in my app instead of assigning strings I would set properties for each control, which I could later retrieve when the control is clicked. I haven't tryed this because I don't know exactly how to do it.
What do you think? Do you know how can I achieve this or do you have a different idea that will work? Please help! Thanks in advance.

It's kind of a broad implementation question since there are countless ways you could implement something like this.
If you are creating two collections, one with the buttons and one with the information, you potentially could just assign each of the buttons 'Tag' properties to point to the corresponding info and assign a generic OnClick event handler that displays the info.. something like:
infoControl.text = ((InfoClass)((Button)Sender.Tag)).pieceOfInformation;
But again there are many ways to do this, and the choice comes down to how you store your information.

For your first method, you could have a property of your custom control that is the index.
public class Box : Control
{
// ...existing code
private int index;
public int Index
{
get
{
return index;
}
set
{
index = value;
}
}
}
OR
For your second method, you could have a property of your custom control that is the additional info string.
public class Box : Control
{
// ...existing code
private string extraInfo;
public string ExtraInfo
{
get
{
return extraInfo;
}
set
{
extraInfo = value;
}
}
}
In either case, you could then access the proper information right in your click handler for the "box".

i don't know about the first way - got to noodle around more, but in the second way you can extended your custom or built-in control: for example:
public class ExtendedLabel: Label
{
public string[] MoreInfo { get; set; }
}
and initialize it
public TestForm()
{
InitializeComponent();
ExtendedLabel label = new ExtendedLabel();
label.MoreInfo = new string[] { "test" };
this.Controls.Add(label);
label.AutoSize = true;
label.Location = new System.Drawing.Point(120, 87);
label.Name = "label1";
label.Size = new System.Drawing.Size(35, 13);
label.TabIndex = 0;
label.Text = label.MoreInfo[0];
}
And later in your event handler you can use the inside information

How can I make a specific TabItem gain focus on a TabControl without click event?

How can I tell my TabControl to set the focus to its first TabItem, something like this:
PSEUDO-CODE:
((TabItem)(MainTabControl.Children[0])).SetFocus();

How about this?
MainTabControl.SelectedIndex = 0;

this.tabControl1.SelectedTab = this.tabControl1.TabPages["tSummary"];
I've found it's usually a best practice to name your tabs and access it via the name so that if/when other people (or you) add to or subtact tabs as part of updating, you don't have to go through your code and find and fix all those "hard coded" indexes. hope this helps.

I realise this was answered a long time ago, however a better solution would be to bind your items to a collection in your model and expose a property that selected item is bound to.
XAML:
<!-- MyTemplateForItem represents your template -->
<TabControl ItemsSource="{Binding MyCollectionOfItems}"
SelectedItem="{Binding SelectedItem}"
ContentTemplate="{StaticResource MyTemplateForItem}">
</TabControl>
Code Behind:
public ObservableCollection<MyItem> MyCollectionOfItems {
get;
private set;
}
private MyItem selectedItem;
public MyItem SelectedItem{
get { return selectedItem; }
set {
if (!Object.Equals(selectedItem, value)) {
selectedItem = value;
// Ensure you implement System.ComponentModel.INotifyPropertyChanged
OnNotifyPropertyChanged("SelectedItem");
}
}
}
Now, all you have to do to set the item is:
MyItem = someItemToSelect;
You can use the same logic with the SelectedIndex property, further, you can use the two at the same time.
This approach allows you to separate your model correctly from the UI, which could allow you to replace the TabControl with something else down the line but not requiring you to change your underlying model.

Look at the properties for the tab control...
Expand the TabPages properties "collection"...
Make note of the names you gave the members.
ie. a tab control called tabMain with 2 tabs called tabHeader and tabDetail
Then to select either tab...You have to set it with the tabname
tabMain.SelectedTab = tabHeader;

tabControl1.SelectedTab = item;
item.Focus();

Basically all of the answers here deal with SELECTION, which does not answer the question.
Maybe that is what OP wanted, but the question very specifically asks for FOCUS.
TabItem item = (TabItem)MainTabControl.Items[0];
// OR
TabItem item = (TabItem)MainTabControl.SelectedItem;
// Then
item.Focus();

tabControl.SelectedItem = tabControl.Items[0];

If you have a Tabcontroller named tabControl you could set the selectedIndex from different methods, i use following methods mostly.
codebehind:
tabControl.SelectedIndex = 0; // Sets the focus to first tabpanel
clientside:
First, put the following javascript in your aspx/ascx file:
<script type="text/javascript">
function SetActiveTab(tabControl, activeTabIndex) {
var activeTab = tabControl.GetTab(activeTabIndex);
if(activeTab != null)
tabControl.SetActiveTab(activeTab);
}</script>
Then add following clientside event to prefered controller:
OnClientClick="function(s, e) { SetActiveTab(tabControl, 0);

it's better to use the following type of code to select the particular
item in the particular tab...
.
private void PutFocusOnControl(Control element)
{
if (element != null)
Dispatcher.BeginInvoke(System.Windows.Threading.DispatcherPriority.Input,
(System.Threading.ThreadStart)delegate
{
element.Focus();
});
}
And in calling time... tabcontrol.isselected=true;
PutFocusOnControl(textbox1);
will works fine...

Private Sub TabControl1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles TabControl1.SelectedIndexChanged
'MsgBox(TabControl1.SelectedIndex)
If TabControl1.SelectedIndex = 0 Then
txt_apclntFrstName.Select()
Else
txtApplcnNo.Select()
End If
End Sub

It worked for me to set focus to the last tab just after I open it:
//this is my assignment of the collection to the tab control
DictTabControl.DataContext = appTabs.DictTabs;
//set the selected item to the last in the collection, i.e., the one I just added to the end.
DictTabControl.SelectedItem = DictTabControl.Items[(DictTabControl.Items.Count-1)];