VB.NET Lazy load controls into flowlayoutpanel - vb.net

I have a flowlayoutpanel with thousands of pictureboxes and even more buttons. I am looking for a way to not load the controls while they are outside the screen so that I don't have to wait for all the controls to load. Much like windows explored folder view works if you have say, a thousand files in a folder, you don't need to wait for all of them to load and display thumbnails.
The code and the way I am generating controls at the moment is:
For Each myDirectory As IO.DirectoryInfo In New IO.DirectoryInfo(ProjectsFolder & SmartHub_Home.ComboBox_Subcategory.SelectedItem & "\").GetDirectories().Reverse
'Programmatically creating controls
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ACCESS VBA Picture saved as OLE OJECT used as Picture property for custom command bar

I have some custom popup menus in my app and i am tired of using the .FaceID property just to set some "not so relevant" images form my commands. What i want to do is to get some pictures saved in a local table OLE-OBJECT field and display those instead of the MS pictures.
The controls of commandbar object have .Picture and .Mask properties which work just fine if i load a file from the hdd into a IPictureDisp object using stdole.LoadPicture, but i don't want to have hundres of small files in my app folder.
So, my question is: is there a way i can get the picture saved in the local table to become a IPictDisp. I can get it's byte array just fine, but i found no way of converting that into something that the Commandbar button can recognize.
Thank you for any help.

How can i take a screenshot of the webbrowser hidden and minimized

I am trying to make a application the takes screnshots of the webbrowser hidden and minimized and put it to a picturebox or save it as a bitmap. I know that there are drawtobitmap, bitblt, copyfromscreen and some other ways, but no one do the job if the control or the form is minimized or hiddenm background. These functions only work if the form is active and foreground. I tried many and many codes based on many kind of tricks to do this, but no one worked.
How can I proceed?

Very slow design view on a complex form with a lot of controls

Let's start with a confession: I came from a VB6 background, and I'm accustomed to coding within the events of objects on a form, and as such my code for events ends up in somewhat random order in the code window. With this habit, it's never been very important to remember the names of controls (although I name them well)... I just double click on a button in the design view, which brings me straight to the code for that control's primary event. If I forget the name of a control, I click it and view properties. It's not a habit I've moved away from.
Well, now this is catching up to me. Using VS Express 2013, I have a form that contains a HUGE number of containers-within-containers, labels, buttons, and other doohickeys. I ported my code from VS.NET Express 2008 where this wasn't a problem. But now the act of selecting any control in the design view takes around 10 seconds before I can view its properties. If I drag to resize a control, and another 10 seconds passes before I can select another control. It makes designing this form nearly impractical.
In this particular project, I'm using use a tab control (which is never visible to the user) to design many "screens" which each contain panels full of controls. The panels for each "screen" are moved out of the tabs and docked into the main form as requested by the user changing screens. (I'm using the term "screen" to mean a window full of controls, usually maximized.)
Within the same project, a simple modal password-change form isn't slow to edit controls visually, even if the complex form is still visible in the IDE.
My question is in three parts:
First, what the heck is it spending all that time doing?
Second, is there a setting I can tweak to improve the speed?
Third, should I give up on trying to speed it up as-is, and move each "screen" into its own form for design purposes to avoid this slowness? (It's a lot of work to do that now... see next paragraph.)
Thus far I have avoided separating "screens" onto separate forms because I don't want a new window to come up when users change screens, and because code for the controls in one screen may affect the properties of controls on other screens... In such cases I prefer not to write out
form.doohickey.text = "blah"
..but rather keep it as ...
doohickey.text = "blah"
I'm using VB but I don't think this question is VB-specific.)
First off, I feel your pain. I have a management section of the application that I'm writing and I'm using a TabControl as well. I have 10 tabs so far and I've only added controls to about 4-5 tabs. I just added up the controls I have and there are about 360 controls so far on this one form and the designer file is ~3300 lines long. Currently anytime I change a property value of one of the controls or go to save the Designer, it takes about 3-4 seconds each time. I have a fairly decent machine; i5-3320M, 8GB RAM, intel 330 SSD, and it still takes a bit for it to do things within the tabControl. It also takes FOREVER to open and load the designer on that form...
What I've found is that it is easier to open a new instance of Visual Studio, create a test application, add a TabControl with the same properties, and design a new tab page from there. When I'm done I do a copy-paste into my actual project. This works great except for the few custom controls I've written in my main application project, I just have to sit and wait while adding them.
I'm now answering my own question. This is the approach I've ended up using, and it helps a lot...
My overall goal was to have an interface that didn't present a lot of windows, but still presented many different "screens".
I used to place all the different controls of different "screens" on separate panels, which were each contained in separate tabs of an invisible TabControl. I would then move those panels to my main form as needed by changing their Parent property of each panel as needed. The only problem with this is that the Winforms designer got ridiculously slow as the number of controls on a form increased into the hundreds.
Now, I am now designing each "screen" as a separate form, each of which contains a panel whose Dock property = Fill. Such a panel contains everything else on the form. The form itself never becomes visible.
As needed for to view various screens, I execute:
ScreenForm.Panel1.Parent = Mainform
...or, depending on how I lay it out...
ScreenForm.Panel1.Parent = Mainform.PanelXYZ
...I also either unload or hide any panels which already exist in the panel's new container.
I was GLADLY SURPRISED to find that the code for the various events of the controls contained in the panels would still run, because such code exists in the first form's file, not the displayed form's file. Luckily, it seems I was wrong. Event code follows the control itself. I can copy/paste not only controls, but also their corresponding event code to new forms for easier development and a faster Winforms designer.
All of this is similar to a MDI interface with maximized windows, but no title bar or [X] is displayed.
Essentially I'm doing everything as I did before, except using separate forms with panels instead of separate tabs with panels. The WinForms designer is much quicker because there aren't so many controls on any form.
I think I accidently found a workaround for saving a lot of time when changing the name of a control on a overpopulated container/project. Before you change the name, toggle False/True the "Generate Member" property of the control you want to rename(I believe you can also locate this under the "Name" property). This adds a few more clicks to the procedure but saves a lot of time. My not-yet-finished project has over 4000 controls and multiple forms and some of them are very "heavy" (10 - 20 seconds to normally change the name of a control). This, of course, don't help in anyway with the loading time of the project (about 35 seconds for me) but I can live with it. Let me know if this works for you too.

Silverlight UI Virtualisation for Listbox with Items having writable bitmap

I have a created a display control with two Columns - 1. A thumbails list and 2. Listbox of images.
The images are written to writeable bitmap and then added to listbox items.
I have created custom tab control so that multiple instances can be opened. The issue here is with multiple tabs open, the memory usage shoots upto 1.2GB.
Is the list box by itself use ui virtualisation?
Want to know if there are any better solutions for this.

Clone Winform control

I have a groupox in a VB.NET winform app. The groupbox contains a few Labels, Textboxes and Checkboxes. This was created by simply dragging the controls out of VS toolbox.
What I need to do is take the 1 Groupbox and at runtime create multiple Groupboxes to display based on user selection. Instead of dynamically creating the Groupboxes and other controls nested inside, is there a way to clone or copy the original one.
Then I'd just change the properties. Label text, Textbox text, etc. And the location of the Groupbox in the layout.
What you could do is create a user control based upon your groupbox which would allow its reuse. You could then create the instances you require at runtime and add them to the form.
Maybe suggest that you look into creating user controls for winforms.
Could this be a help to you?
How to Clone/Serialize/Copy & Paste a Windows Forms Control