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Debugger Visualizer Winform ToolStripDropDownMenu ComboBox only shows items when first shown

I have a Visual Studio debugger visualizer project, and when I add a ToolStripComboBox to a ToolStripDropDownMenu, the combobox's items only appear the first time the form is shown.
Like this:
The most basic version of the winform code showing the issue is this:
public class MyVisualizerDialog : Form
{
public MyVisualizerDialog()
{
var toolStripComboBox = new ToolStripComboBox
{
Items = { "One", "Two", "Three" }
};
var toolStripDownDown = new ToolStripDropDownMenu
{
Items = { toolStripComboBox }
};
var toolStrip = new ToolStrip
{
Items =
{
new ToolStripMenuItem("Options")
{
DropDown = toolStripDownDown
}
}
};
Controls.Add(toolStrip);
}
}
Then the visualizer code is simply:
public class MyVisualizer : DialogDebuggerVisualizer
{
protected override void Show(
IDialogVisualizerService windowService,
IVisualizerObjectProvider objectProvider)
{
windowService.ShowDialog(
new MyVisualizerDialog());
}
}
Some extra details:
If I add the ToolStripComboBox to ToolStripMenuItem.DropDownItems, it works fine - it seems to specifically be an issue with having a ToolStripComboBox in a ToolStripDropDown.
If I create and open multiple instances of the same form class in a console app, it works fine.
Once the issue occurs, it keeps occurring - even when I revert the code to the version without the ToolStripDropDown
If I restart Visual Studio, it works the first time the form is shown, then not afterwards.
Any ideas?! Anyone know some wrinkle in the way the IDialogVisualizerService disposes controls or something?!
Thanks for reading :)

It appears that, when the debugger visualizer is closed - which is handled in the debugger side, not in the debuggee side - the DropDown is destroyed but the ToolStripManager doesn't know about it and it finds itself with an invalid handle that it doesn't know how to manage.
Since the ToolStripManager is also active in design mode, this propagates the problem throughout the designer interface: you may find that some DropDown items still work after the debugger visualizer has been closed, but you may not be able to add other ToolStripComboBox items anywhere.
If you insist, also those that appeared to be working may not work anymore.
Note that this misbehavior can translate to ComboBox objects; not directly, but when you try to access their Items collection through the interface.
It may also prevent the Project from compiling.
Explicitly disposing of the Form object created in the debugger visualizer side, can partially solve the problem on the debuggee side, but not, as it turns out, on the debugger visualizer side.
A simple solution is to avoid setting the DropDown object of a ToolStripMenuItem and use a MenuStrip instead, adding Items to a ToolStripDownDown.
Create custom data visualizers
Visualizer Security Considerations
Sample debugger visualizer (simple Image visualizer) to test the good and bad behavior.
▶ Create a Class Library Project, Target Framework set to .Net Framework, AnyCPU profile.
▶ Add a reference to [Visual Studio install Path]\Common7\IDE\PublicAssemblies\Microsoft.VisualStudio.DebuggerVisualizers.dll and System.Windows.Forms.
▶ Compile the .dll as Release.
▶ Copy the .dll to the \Common7\Packages\Debugger\Visualizers directory of your current Visual Studio installation path.
▶ Start a debug session, add a breakpoint where an Image/Bitmap property is set/loaded and use the magnifier tool to open a preview.
using System.Diagnostics;
using System.Drawing;
using System.Windows.Forms;
using Microsoft.VisualStudio.DebuggerVisualizers;
[assembly: DebuggerVisualizer(
typeof(ImageVisualizer.DebuggerSide),
typeof(VisualizerObjectSource), Target = typeof(Image), Description = "Test Visualizer")]
namespace TestVisualizer
{
public class DebuggerSide : DialogDebuggerVisualizer
{
override protected void Show(IDialogVisualizerService windowService, IVisualizerObjectProvider objectProvider)
{
var image = (Image)objectProvider.GetObject();
var form = new Form();
form.ClientSize = new Size(image.Width, image.Height);
form.FormBorderStyle = FormBorderStyle.FixedSingle;
form.SuspendLayout();
// ------- WORKING CODE ---------------
var menuStrip = new MenuStrip() { };
var tsComboBox = new ToolStripComboBox { Items = { "One", "Two", "Three" } };
var toolStripDownDown = new ToolStripMenuItem() { Text = "Options" };
toolStripDownDown.DropDownItems.AddRange(new ToolStripItem[] { tsComboBox });
menuStrip.Items.AddRange(new ToolStripItem[] { toolStripDownDown });
// ------- WORKING CODE ---------------
// ------- BAD CODE ---------------
//var toolStripComboBox = new ToolStripComboBox { Items = { "One", "Two", "Three" } };
//var toolStripDownDown = new ToolStripDropDownMenu { Items = { toolStripComboBox } };
//var toolStrip = new ToolStrip {
// Items = { new ToolStripMenuItem("Options") { DropDown = toolStripDownDown } }
//};
// ------- BAD CODE ---------------
var pBox = new PictureBox() { Image = image, Dock = DockStyle.Fill };
//form.Controls.Add(toolStrip);
form.Controls.Add(menuStrip);
form.Controls.Add(pBox);
form.MainMenuStrip = menuStrip;
form.ResumeLayout(false);
form.PerformLayout();
windowService.ShowDialog(form);
form?.Dispose();
}
}
}

Populating winform ListView from Calling External Class, not adding image and text

I am trying to add a new image list with text describing each image below each image. I have set the listview to large icons and tried many other attempts to get preview images back into the first form.
I have been able to either
1. get very small images into the list view
2. get just the text into the listview
3. get the very tiny images again with text first then the images, not together.
I have tried all the overloaded methods and I am still at a loss as to why i can't even get a Properties.resources.image in as an image placeholder. except as a tiny image. And yes I have set the listview large icon mode and tried the imageSize properties, nothing works. Also some attempts usually with a technique that appears like it is following an explanation on here fails to show anything in the listview on the frstForm.
Any hints would be appreciated.
public ImageList imageList_c = new ImageList();
private Family_Loader_ExtEventDialog _frstForm;
foreach (KeyValuePair<string, Bitmap> kvp in element_Dict(_doc_new, BuiltInCategory.OST_Walls))
{
//imageList_c.ImageSize = new Size(120, 120);
//imageList_c.Images.Add(kvp.Key, Properties.Resources.folder);
_frstForm.listView_Family.Items.Add(kvp.Key);
}
//_frstForm.listView_Family.LargeImageList = imageList_c;

imageList_c.Images.Add(kvp.Key, kvp.Value);
_frstForm.listView_Family.View = System.Windows.Forms.View.LargeIcon;
_frstForm.listView_Family.LargeImageList = imageList_c;
for (int i = 0; i < imageList_c.Images.Count; i++)
{
ListViewItem item = new ListViewItem();
item.ImageIndex = i;
item.Text = imageList_c.Images.Keys[i];
_frstForm.listView_Family.Items.Add(item);
}

Can't Add Tab Page To TabControl Inside The Constructor Of My WinForms Application

I have a C# Form application that has a TabControl in the main form. This TabControl is used to display multilple TabPages that contain a CustomControl. This CustomControl is just a Panel with a few buttons and a PictureBox.
Here is a picture of my app when it starts up. As you can see the tab control (the white area) is empty:
If the user clicks the "Add Image" button they are presented with an OpenFileDialog to select the image then the addImage method is called with the selected file:
private void doAddImage()
{
OpenFileDialog openFileDialog = new OpenFileDialog();
openFileDialog.Filter = Constants.Global.IMAGE_FILE_FILTER();
if (openFileDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
string imageFileName = openFileDialog.FileName;
addImage(imageFileName);
}
}
private void addImage(string imageFileName)
{
// Create a new bitmap and image preview custom control. Then create a new tab
// page and add the custom control to the tab page.
Bitmap bitMap = new Bitmap(imageFileName);
ImagePreviewCustomControl previewControl = new ImagePreviewCustomControl(bitMap);
previewControl.Dock = DockStyle.Fill;
TabPage tabPage = new TabPage(Path.GetFileNameWithoutExtension(imageFileName));
tabPage.Controls.Add(previewControl);
// Insert the new tab page to the right of the currently selected tab page
int selectedTabIndex = imagesTabControl.SelectedIndex;
imagesTabControl.TabPages.Insert(selectedTabIndex + 1, tabPage);
imagesTabControl.SelectedIndex = selectedTabIndex + 1;
}
As you can see, in the addImage method I create the Bitmap, CustomControl, and TabPage and then insert it into the TabControl.
I start my application, click the "Add Image" button, everything works just fine.
Here is a picture with a tab page added:
While I am testing my app I don't want to have to add an image manually using the OpenFileDialog every time so in my constructor I just call addImage with some fixed image file name that I want to test with:
public ImageViewerApp()
{
InitializeComponent();
addImage(#"C:\MyImages\Calculator-3-icon.png");
}
The problem I am having is that when I try to add the image in my constructor it doesn't show up in the TabControl. The application starts up blank (like the first picture).
As stated above when the application is already running and I click the "Add Image" button it gets added just fine.
I found a property in the TabControl class called Created which states:
"Gets a value indicating whether the control has been created"
So to try and figure out what's going on I write the value of Created to the console just before I call addImage in the constructor. (I have a custom console for debugging my Form applications.)
public ImageViewerApp()
{
InitializeComponent();
TestConsole.WriteLine(imagesTabControl.Created);
addImage(#"D:\Development\Work\Other\Stardock\Start8\_downloaded\Calculator-3-icon.png");
}
The value of Created just before the call to addImage in the constructor is:
False
I put another console output inside the addImage method:
private void doAddImage()
{
TestConsole.WriteLine(imagesTabControl.Created);
OpenFileDialog openFileDialog = new OpenFileDialog();
...
...
}
The value of Created after the app has started and the user presses the "Add Image" button is:
True
Why is it that the TabControl is not Created inside my constructor (even after the InitializeComponent() call) and the once the application is running it is Created?
=UPDATE========================================================================
Based on the suggestion by Hans Passant I have added the following code to my addImage method:
int selectedTabIndex = -1;
if (imagesTabControl.TabCount > 0)
{
selectedTabIndex = imagesTabControl.SelectedIndex;
}
else
{
selectedTabIndex = imagesTabControl.SelectedIndex + 1;
}
imagesTabControl.TabPages.Insert(selectedTabIndex, tabPage);
imagesTabControl.SelectedIndex = selectedTabIndex;
This doesn't work.
===============================================================================
=UPDATE2=======================================================================
int selectedTabIndex = imagesTabControl.SelectedIndex;
if (imagesTabControl.TabCount == 0) selectedTabIndex = -1;
imagesTabControl.TabPages.Insert(selectedTabIndex, tabPage);
imagesTabControl.SelectedIndex = selectedTabIndex;
This causes the following Exception:
{"InvalidArgument=Value of '-1' is not valid for 'index'.\r\nParameter name: index"}
===============================================================================
=UPDATE3=======================================================================
I tried the folllowing code:
int selectedTabIndex = imagesTabControl.SelectedIndex;
if (imagesTabControl.TabCount == 0) selectedTabIndex = -1;
imagesTabControl.TabPages.Insert(selectedTabIndex + 1, tabPage);
imagesTabControl.SelectedIndex = selectedTabIndex + 1;
This one doesn't throw an exception but again no tab page added after calling
addImage in the constructor.
===============================================================================
=UPDATE4=======================================================================
I have kindof given up on adding an image in the constructor. So instead I am using an enum RunMode and a variable RUN_MODE of that type. Then, if RUN_MODE == RunMode.TESTI call a method to add a random image when I click the button. (The OpenFileDialog is not used. I just parse through all the image files in the fixed directory IMAGE_DIRECTORY.
enum RunMode { NORMAL, TEST }
private static string IMAGE_DIRECTORY = #"D:\\Work\Images";
...
...
private void doAddImage()
{
if (RUN_MODE == RunMode.TEST)
{
addRandomImage();
return;
}
OpenFileDialog openFileDialog = new OpenFileDialog();
openFileDialog.Filter = Constants.Global.IMAGE_FILE_FILTER();
if (openFileDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
string imageFileName = openFileDialog.FileName;
addImage(imageFileName);
}
}
private void addRandomImage()
{
string[] allFiles = Directory.GetFiles(IMAGE_DIRECTORY);
List<string> imageFileNames = new List<string>();
foreach (string file in allFiles)
{
bool isImageFile = Constants.Global.IMAGE_EXTENSIONS.Contains(Path.GetExtension(file));
if (isImageFile)
{
imageFileNames.Add(file);
}
}
int randomIndex = new Random().Next(imageFileNames.Count);
addImage(imageFileNames.ElementAt(randomIndex));
}
This works. Now when I click the "Add Image" button during TEST_MODE I skip the
OpenFileDialog and just add a random image.
I would like to understand the issues with TabControl but at this point I just
need to continue development. My current solution works great.
As I person who like to understand everything I would like to use other people's
suggestions so I will keep monitoring this question for a solution.
===============================================================================

JonP's answer gave me the idea to just wait for the window handle to be created before inserting the tab, so I tried some events occuring between Form construction and Tab Control display.
I found it to work with both the Load or Shown events:
Right-click on the Form (the root, not child controls) in the Designer view > Properties > Events (flash icon) > Behavior > enter a method name for the Load or Shown event and confirm. To generate a Load event callback you can also double-click on the Form itself. This should generate something like this:
this.Load += new System.EventHandler(this.Form1_Load);
// or
this.Shown += new System.EventHandler(this.Form1_Shown);
Setup the tabs in the callback:
private void Form1_Load(object sender, EventArgs e)
{
// Add image (this will call imagesTabControl.TabPages.Insert(selectedTabIndex + 1, tabPage))
// This must be done on Load event because Insert requires
// the window handle, which is not ready in the constructor
addImage(#"path_to_image.png");
}

I have had this problem too and have found a workaround; I think it must be a bug with Insert():
Don't use Insert(), it usually does nothing, use Add() instead; this reliably adds a TabPage to the end of the collection.
After adding it swap it with the tab position where you actually want it.
imagesTabControl.TabPages.Add(tabPage);
// Now swap the two tabs:
imagesTabControl.TabPages[imagesTabControl.TabCount - 1] = imagesTabControl.TabPages[selectedTabIndex + 1];
imagesTabControl.TabPage[selectedTabIndex + 1] = tabPage;
Your mileage may vary of course :-)
Stop Press! An even better fix is to read the class's Handle member before calling Insert():
var handle = imagesTabControl.Handle;
Insert() works perfectly after you do that. Obvious isn't it???? The help page for Handle has this possible relevant Remark showing that the object actually does something when you read Handle:
The value of the Handle property is a Windows HWND. If the handle has not yet been created, referencing this property will force the handle to be created.

You could remove the TabControl from the designer and then instead just manually create the TabControl programmatically and add it to the Form immediately after InitializeComponent(). Then after you create the TabControl, call addImage(). Something like:
InitializeComponent();
TabControl tc = new TabControl();
tc.Location = new Point(10, 10);
tc.Size = new Size(100, 100);
tc.Visible = true;
tc.Anchor = (AnchorStyles.Bottom | AnchorStyles.Right | AnchorStyles.Left | AnchorStyles.Top);
this.Controls.Add(tc)
addImage("c:\pathToImage\image.bmp");

winforms listview not showing items in detailsview

i'm stuck....
this my code to add items to my listview:
ListViewItem item = new ListViewItem(ProjectDomainName);
item.Tag = relatedProject.ProjectId;
lvwSelectedProjects.Items.Add(item);
when i choose 'View.List' as viewmode, i see all items.
When i choose 'View.Details' (which is the setting that i want) i see.... nothing. Well, nothing, i DO get a vertical scrollbar, but no items. And i can scroll too, but no items....
I also added a column in the listview (didn't change the add items code), but that also didn't work
i must be overlooking something?

This code works for me:
using System;
using System.Windows.Forms;
public class LVTest : Form {
public LVTest() {
ListView lv = new ListView();
lv.Columns.Add("Header", 100);
lv.Columns.Add("Details", 100);
lv.Dock = DockStyle.Fill;
lv.Items.Add(new ListViewItem(new string[] { "Alpha", "Some details" }));
lv.Items.Add(new ListViewItem(new string[] { "Bravo", "More details" }));
lv.View = View.Details;
Controls.Add(lv);
}
}
public static class Program {
[STAThread] public static void Main() {
Application.Run(new LVTest());
}
}
Try this code for yourself in an empty project. Then, focus on adapting it to your application: compare how your program is different from this code, and work on changing it to more closely match mine. It's OK if you lose functionality in your program; just try to get a basic version working. Then, add functionality back bit by bit so you can be sure that the program still works every step of the way.
If you're still stuck, post more code from your project and we might have a better idea of why you're having trouble.

Another possible cause of blank items when listview.View = View.Details, is if you don't add any columns to the listview.
For example:
ListView lv = new ListView();
lv.View = View.Details;
lv.Items.Add("Test");
.. will result in a blank ListView.
Adding a column will correct:
...
lv.View = View.Details;
// Add one auto-sized column, to show Text field of each item.
lv.Columns.Add("YourColumnTitle", -2);
...

Because, you should be using a ListViewDataItem instead of a ListViewItem, observe ...
for (int i = 0; i < AudioCdWriter.FileCount; ++i) {
var item = new ListViewDataItem(i.ToString());
item.SubItems.Add(AudioCdWriter.TrackLength((short)i).ToString());
item.SubItems.Add(AudioCdWriter.file[(short)i]);
lvwAudioFiles.Items.Add(item);
}

This happened to me as well (listview not showing items in details view) I just put the following into the code (previously was only in the design) after adding items to the listview and it started showing the items.
lv.View = View.Details;

ListViewItem item = new ListViewItem("item1");
item.SubItems.Add("subitem"); //add subitem if applicable
listview1.Items.Add(item);
this Result can be sold your problem

C# .net Windows Forms Listview with image in Detail View

I want something like this develop using C# .net for Windows Forms. (ListView Details View). Putting a Image is the problem.
Help me ..!!
Thank You
Yohan

Hope that the following code can help you out.
using C#
ImageList il = new ImageList();
il.Images.Add("test1", Image.FromFile(#"c:\Documents\SharpDevelop Projects\learning2\learning2\Koala.jpg"));
listView1.View = View.LargeIcon;
listView1.LargeImageList = il;
listView1.Items.Add("test");
for(int i = 0; i < il.Images.Count; i++)
{
ListViewItem lvi = new ListViewItem();
lvi.ImageIndex = i;
lvi.Text="koala 1";
listView1.Items.Add(lvi);
}
Running this kind of code can get you the image and the text in a listview.
For further more details, refer to this post

You may want to take a look at this Code Project entry.
Extended ListView