Interface And Graphics :: Listbox Event - Scrollbar That Comes With ListBox Is Too Small For Touch Screens
Jan 6, 2011
The scrollbar that comes with the ListBox is too small for touch screens, so I use my own scrollbar instead. But when you do this on various forms you end up repeating a lot of code. So my solution was to create a custom scollbar that has a property I can set to the control I want it to be a scrollbar for. In vb6, I can use the withevents keyword to get access to the control's events so that all the scrollbar related code can be in the custom scrollbar object I created, except...I had to create a refresh method for the consuming code to use to let the scrollbar know when the number of items changes. The scrollbar doesn't need to be told how many items there are because it has access to the control, but for a listbox there is no event to tie into when an item is added/removed so not 100% of the scrollbar related code could be encapsulated.
On my form is a listbox. When the user clicks insert (in the menu) then I add a blank item in the listbox. The user then enters the data and then I want to update my listbox with the value(s) the user entered. The problem is that I don't see the update in the listbox, unless I reload it from the database. [Code]
I'm trying to build a custom ListBox control as inspired by the 'Audi Infotainment System' on high-end Audi vehicles. The only difference is i would like to have a 'boundary' where when scrolling up/down moves the actual list up or down. Basically, i would like my list to act like a normal ListBox except i would like to show say one or two items above and below normally only visible items.
I don't usually use VB but now I must for an assignment. I would like to know if it's possible to change the display name for an object on a listbox. For instance, if I add to it a user defined class, there's a way to provide it's display name, instead of converting it to string and then add it.
This is what I have
Dim format As String = FormatOutput(object) Lista.Items.Add(format)
I would like to have the same output, but instead add the object.
Note: if such is not possible, then how can I associate the list box selection to the actual object? Doing it by index is painfull, because I'm using linked lists (ie., instead of arrays).
Note 2: python has a __str__ method which is called by default when the object is cast to string. Is there anything like it in VB?
So, in my vertical scrollbar, the maximum value is 16. In my application, I made a Label to track the scrollbar's value, just for testing purposes.I noticed that when I move the bar to the bottom, the value is 6. And when a release the button (stop holding it with the mouse), the value becomes 7.
Something similar goes when I move the button to the top: It is 1, and when I release the button, it becomes 0.That's a bit weird, but what mainly bugs me is why I cannot reach value 16?
I'm developing a GUI for a touchscreen, so when user wants to scroll he/she uses their fingers. Now the thing is that the scrollbar width (with the vertical scrollbar) IS adjustable but the button stays the same height and isn't sufficient for a finger. So the question is : Are the buttons in the scrollbar allso adjustable in size/dimensions.
I have a form and on it there is listbox. What I want to do is to make the listbox's backcolor transparent. I really do not understand. I have searched many sites but I couldn't find an exact answer. Is it really that hard to make it??? I found this code on a few sites:
I have a listbox which content is based on a treeview. When the user doubleclicks an item in the listbox the treeview will be updated and aftervards all the items in the listbox will be removed and the text of each TreeNode in the TreeView will be addedto the ListBox
Im trying to fill a ListBox with more than 65542 items in a Visual Basic .NET 2008 project. The ListBox seems capable to collect 100000 articles, but when i scroll through the list the scrollbar works till the 65500th listing (more or less) then it just jumps upwards.The weird thing is that I have two version of the same project which have different behaviors. One (tmp.zip) scroll fine with the scrollbar, but it doesn't with wheel mouse button.The other (listBox.zip), the scrollbar goes mad but mouse wheel seems ok
listobox.zip: is a new project created within VS 2008 tmp.zip: is a cleaned up form imported in VS 2008 from an early version (VS 2003?)
I have been working on a much larger project and came to a point where I decided threading should be used.It seems in previous version of .Net, a background worker was able to update controls that were were not created on that thread. Now, it doesn't seem to be the case.I basically just began a new small project to try and teach myself the basics.Form1 Consists of A listbox, A progress bar, a label and two buttons, one to start and one to cancel.
imports system.threading private sub btngo(byval sender as system.object, byval e as system.eventargs) handles btngo.click pbprogress.minimum = 0[code=....
This code appears to be updating the listbox.I can see the vertical scrollbar getting smaller, but no data is shown in the listbox. The progressbar is also updating properly while that is working, indicating proper background operation.But what it's not doing is this:
1. Label is not updating percentage
2. The form is not free to be used by the user (me)
Very simply, I'm positioning a small ListBox over a DataGridView column when the user right-clicks and selects "Show Distinct Values". This works fine until the vertical scrollbar of the DataGridView is clicked. Once that's done the listbox pops up all the way over to the left edge of the DataGridView. As confirmation of the problem I created a small app to test with.
I have a listbox on my form which gets items added as the program progresses, when there are more items than the box can display, the vertical scrollbar appears, fine... so far so good.I would like the scrollbar default position to be at the bottom of it's column so that the last entered item is displayed but can't find the relevant command, I assume there is such a command.
If I set a ListBox.Height = ListBox.PreferredHeight when the control is hidden and IntegralHeight = True, then set it visible:
a) Actual Height reduces by typically 3-5 pixels after redraw (but not 1 pixel per item).
b) PreferredHeight does not not appear to give the correct integral of item heights.
Is there a way to make ListBox calculate the correct integral Height before the ListBox is made visible, so it can be correctly pre-positioned from bottom edge?
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
This is a working example which draws a rectangle on different location every timer_tick and I fully understand now how it's working:
Code: Dim i, timercount As Integer Private Sub PictureBox1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles PictureBox1.Paint
[code]....
Now I'm looking for a way to draw this rectangles without refreshing them every single tick. I've just started using Visual Basic and I really don't know how to call/raise PictureBox1_Paint event every timer_tick or how to store drawing data in member variables?
In a application i'm working on i need to be able to select a graphic (a line to be specific) and then i need to change or move it but i cant find how to add a click event to the line when a draw it. Basicly i want to click on the line to select it (make it fatter or an other color) and then be able to alter it in position and size (lenght). Is there any way or what is the correct way to do this?
I've got this code which draws a line and it moves down to a point then two curves are drawn coming off of it. I need to get it to repeat itself after a short period, so there's a constant flow of lines moving down then becoming curves.[code]
Is it possible to detect a mouse leave to the left. For example: I have a label and when I hover over it the text changes to "Hovering", and when I leave the label from the left I want the text to change to "Exit left" or if I leave the label from the right that text changes to "Exit right".
Back in the VB6 days, I could count on frmWhatever_Resize() to be fired when a form is loaded. That doesn't still seem to be the case. Since my resize event is filled with all the code I want that adjusts the size and placement of things, I decided to just call it from the end of the form's load event. That has no affect. I'm guessing that the form isn't actually shown until form_load is finished?
is there some other event that is fired when a form is shown, so I can call my resize code there?
I am using VB.NET (version 2008). I have two types of items populating in a listbox (checked listbox). For example: lets say one is type "A" and other is "Type B". Their names maybe same so if the user sees those items in listbox then he won;t be able to determine their type until he click on them and checks out its properties. I wanted that I add each item to listbox and colour them so that blue for example means type "A" is there and red means the other. So this way I will be able to know at a glance that how many item of what type is present. I guess it may not be possible to do that in a standard checkedlistbox. I am also using component factory's krypton controls which enhance the gui of an application. But I dunno if I can progress using that.
Im working on a project that needs to print a report of one client.Everything went smooth untill i came across my multiline input text data.When i display it in the PrintPagePreview the text go's outside my page. Even when im printing it only the halve of my text is displayed. I googled and looked everywhere but i can't get a clear fix for it.
I used to program with Visual Basic 6, so I have alot of old programs that I'm updating, plus I'm learning the new VB2008 methods. I'm writing a program that replaces the old "BitBlit" function which is no longer supported by Visual Basic 2008. It involves three picture boxes, one holds the sprite bitmap, a second holds the mask (silhouette) of the sprite bitmap, and a third has a background image.
drawing text on a window which is not the current form's window.I remember doing this in Win32 api with getwindowdc(handle) to obtain a DC for the Window, then textout() on the DC.
