VS 2008 : Handle Some Event Related To When The TreeView Scrollbar Appears Or Disappears?
Sep 12, 2009
I have a custom contro which inherits directly from Treeview. Is there any way to handle some event related to when the TreeView Scrollbar appears (it does this when the height of the stack of visible nodes exceeds the height of the control) or "disappears"?
I realize if could set up a function which checks the ItemHeight * Nodes.Count, and compares this to the control height. However, this seems clumsy. I have been exploring the object browser (and anylized TreeView with Reflector) and have not found what I am looking for. If there is a way to access the ScrollBar Property at ALL within TreeView, I have not found it.
I am trying to use a scrollbar to move forward and back through records in a datatable and to populat an entry in a field to indicate that individual records are selected.In short i want to represent a the sum of a specific field of those records selected. Of course being a scrollbar it has to work in reverse and unselect records when the user moves it backward.
The purpsoe of the scrollbars is that there will be five of them and they will represent years. The records on the other hand represent projects which have an output (say money saving). The idea being projects selected in year one then cant be selected in year two. I am planning to do this by assigning a value that indicates they are already allocated to the previous or other years scroll bar. I can set up a loop to go through the whole data set and do this for a year (and have), but i want to use scrollbars and make it interactive.
is it allowed to use more than one Sub to handle the same event ? For example , may I have 2 separate subs to handle the Load event of a form ? Will they fight each other ?I have tested it and it seems to work fine , nevertheless I thought I'd ask you . In case you wonder , there is no great deal , I just want to copy the same lines of code in more forms so I am doing it just in favor of the looking aspect .
I have a treeview control that gets populated at runtime with a pyramid of employee names. I put the css scrollbar on the view by putting overflow: auto" in the tag where the treeview is located. The users are now asking me to to have the scrollbar go down in the treeview where a treeview item is selected.How do I make a scroll bar to go to a place where the treeview has been selected?[code]
I have a treeview control where I am dynamically selecting a node depending on user interaction. when a node is selected I want to be able to have the scrollbar go to the location of that selected node in the tree. The scrollbar is simply made by overflow:auto in the div tag where the treeview is located. Can someone give me some detailed code to accomplish this?
Say I have a button that creates more buttons with a random .Text property, and placed them on the form in different locations. And since these buttons are being created at runtime, I want to be able to have an event handler for all button controls on the form that makes the form's text the same as the sender's text.
Is it possible to handle a groupbox rightclick-event in VS 2008? I want to display a dropdown menu when my groupbox is rightclicked, but it seems that a groupbox doesn't have a click-event... Is there a way to make this happen?
Is there another way to handle the leave event of multiple textboxes other then coding in each event handler? I may not be using correct terms instead of doing this: (Existing) Private Sub leveladjstvaltxt_Leave(ByVal sender As Object, ByVal e As System.EventArgs) Handles leveladjstvaltxt.Leave If Me.leveladjstvaltxt.Text <> "" Then Dim levels As Integer = CInt(Me.leveladjstvaltxt.Text) Me.leveladjstvaltxt.Text = Format(levels, "#,###")
I have 30 TextBoxes all need same formatting , so I was trying to come up with something like this: (trying) For Each ctrl As Control In Me.Controls If TypeOf ctrl Is TextBox And ctrl.Text <> "" Then Dim val As Double = CDbl(ctrl.Text) CType(ctrl, TextBox).Text = Format(val, "#,###") End If
I am stuck though and don't know where I would place that code if this is something that is even possible. Only thing I can currently think of is in the leave event which defeats the purpose, I wanted to avoid having to place the code in 30 different textoxes leave event.
I have a ListView object with the View property set to Details.I also have the CheckBoxes property set to True. Now, how do I get the user's input if they choose to check a box? Right now I am using the ItemCheck event, but that code runs even when I add something to the ListView object.What is the proper way to handle the event of when the user checks/unchecks a checkbox?
I have a UserControl with a Panel (Panel1). The UserControl has a property Items (type ControlCollection) that returns the Controls collection of Panel1.Via a custom CollectionEditor, I tell the designer that it should add my custom controls called Item (inheriting Control). For the sake of example, the Item control is just a control with a random background color:[code]The custom CollectionEditor creates new Item controls using the DesignerHost service (and its CreateComponent method), so that they appear as actual components in Panel1, selectable during design-time just like any other control.It might be a little hard to see (because the colored Items are docked to the top), but I have selected the red item, which can also be seen from the Properties list.
As you can see in the code, I attach a Click event handler to each item as it is added to Panel1. When clicked, a MessageBox shows the color of the item. Obviously this is just for the sake of this example, but the point is that I need to be able to click an item and something then needs to happen.This works fine during run-time. I can click each item, and the MessageBox shows.The problem is that it does not work (quite obviously) during design-time. When I click it during design-time, it is simply selected (as any other control) and of course does not register any Click (nor MouseClick) events.But, I need the Click event to fire even when in design-time! Clicking an item corresponds to selecting it, and when selected (even in design-time), some other panel (not shown in this example) should be brought to the front so it gets visible. Now, I have created lots of things very similar to this (clicking an item during design-time), but there has always been one major difference: those items were not actual controls on the form. Instead, they were drawn manually on to their parent (and they only looked like separate controls). Obviously there was no design-time support for those 'items' (as they weren't controls), but I could handle clicking them quite easily: by handling the MouseClick event of the parent, I can check the location and see if it falls within an item. If so, that item was 'clicked' (artificially).This time, the items are actual controls, and this method does not work (the parent does not receive a MouseClick event either).So, does anyone know of any way to do this? The only way I can think of right now (although I have no idea how to implement it) is to somehow 'listen' to changes in the designer selection.
I would like to use a treeview control to display related data as Folders(Level0), Projects(Level1), Drawings(Level2). So far I don't have a problem reading data from a database, creating classes to hold the data and displaying the tree from the class data. I have created (3) contect menu strips, one for each level of the tree to perform various tasks. Each menu has an ADD option to either add a folder, add a project or add a drawing.My problem is as follows...After I add the node, in the correct location, I would like to have it set in the BeginEdit mode.
Dim oNode As New TreeNode oNode = TreeView1.SelectedNode.Nodes.Add(sNextID, "New Project") oNode.ImageIndex = 1 TreeView1.Refresh()
[code]....
After this code runs, the node.Text changes back to "New Project". As you can see, I added a few debug.print statements to try to see what is going on. It really blew my mind to see that the entire tree printed in the immediate window.I have already created a work around for this, but is isn't really the way I'd like to see the program run.
I create some vscrollbars dynamically and add scroll event handlers to them. I really want to detect when the user has finished scrolling with a mouse up event but this doesn't seem to be part of the scrollbar events.
I have a filesystewatcher object. On it`s event it runs a procedure which fills a treeview with a data. I had problems with treeview methods, but when I run them using invoke method everything is ok. But I still have one problem. When I load the form for the first time, everything works fine. But, when I then close the form (me.dispose, me.close), and load it once again, when Filesystemwathcer start the procedure i have an exception "invoke or begininvoke cannot be called on a control until the window handle has been created" trying to run a treeview.invoke method?
I am currently working on a VB.Net program where there are two parallel multiline text boxes like this.
----- ----- | | | | | | | | ----- -----
I would like that when one text box is scrolled, the other is scrolled as well. I was wondering if there was a Scroll event that could trigger the change the position of the scroll bar of the two text boxes.
So with the stock Textbox, I set the Scrollbars property to Vertical. This is great if the text in my box never changes; I can scroll up and down while the box sits still. If I'm running a background operation that logs output to the box though, the scrollbar resets itself to the top every time I append text to the box.
I know I can set the Textbox.Selection property (or use the Select method) to reposition the carat in the textbox, make note of that position in a variable, then append text, reset the carat, and use the ScrollToCarat method to reposition the scrollbar where it belongs. That's a really (ridiculously) long way around. Anybody know if there's another/better way of holding the scrollbar position, short of actually building a custom control (or using a Textbox and a separate Scrollbar)? It never hurts to try. In a worst case scenario, you'll learn from it.
All of a sudden a bindingnavigator that I use has started disappeared when I run the program. It disappears in the design view too, but if I click its name down below (where all the datasets and bindingsources go) it comes back. Then once I run again it doesn't show up. I know it's still technically there because no errors in code occur, but why is it doing this?
I have referred DLL in my project. I have to handle the event from DLL in VB.net code. I guess we can do using WithEvents. Can you give me complete picture?
[code]But even here it seems the handler isn't registered until after New has completed.However, in real life the event is raised within code that's semantically part of the object initialisation, and I'd really rather not have to create some Initialize function.
I have a main form "Parent" and another "child" form. When I am filling a textbox in the child form the mouse pointer disappears. Then I hit the tab key to jump to a combobox. At this time when I move the mouse, the pointer doesn't come up until I click the mouse button. This is annoying and the user of my program doesn't like it. How can I keep the mouse pointer always on top. NOte: although the main form has the parent property as true, the other child form are not defined as child forms.
I have a problem to handle an event on a custom control a have on a form.... So first i made a custom control that is just a groupbox with some labels and txtboxes. That control i add dynamically to my form like this (Baycontrol is the name of my control)
Declaration
Code: Friend Bay(29) As BayControl Add the controls to Form Code: For Simindex = 0 To 29 'Me.Bays - 1
I have been reading up on this, but I can't get it to work for me. I am reading in comma delimited text into a three-column datagridview control. The third column is a combo box which only accepts certian values. If the data being imported into col 3 is not in the combo box list I get an error that tells me to handle the data error event.trying to capture that error and get rid of the default error message box. I am working with a Try/Catch statement, but it doesn't seem do anything.
Do Until fileReader.EndOfStream stringLine = fileReader.ReadLine() If Not stringLine.StartsWith("'") And Trim(stringLine) <> "" Then
I must be missing something really basic, but I just can't figure this out. I have a module (declared as a Module, i.e. a VB "static class") and I have an event declared in it, and places to raise the event. But I can't figure out how to handle the event.
Let's call the module MyModule with an even MyEvent. Like so:
Module MyModule Public Event CallHelp() Sub ExamineStuff( ByVal input As String)
I have a mouse click event for one of my controls. I then change the text of that control to something. I also have several other textboxes and want to do the same. How can this be done? I thought maybe this:-
Private Sub txtTitle_MouseClick(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles txtTitle.MouseClick, txtTitle2.MouseClick End Sub
My problem is how do I determine which has triggered the event (title1 or title2).
I use VB.NET 2010 I have created a user control which holds a few textboxes, where the user can find articles. This user control is added to several Forms (where ever the search is needed). I have to handle the key down event of the user control, but it isn't working... The usercontrols's Key_Down Event is never fired. - I have set KeyPreview of the form to true, then the Key_Down of the Form is fired.
I cannot Unresolve a post.I have a datagridview control with a combo box. The user loads data from a file into the control. If there are errors (the element in the combo box column is not in the combo box list) I would like to:
1. capture the row in which the error occurred, and store it in code/memory 2. change the cell backround to red (this is not that important) 3. continue without a message at the time of the error 4. post a message with all of the errors after the load is complete
I am using the code staight out of the Microsoft example to try to figure how to do this, but it is not posting any messages when I load bad data, so I am not getting any smarter from the example.[code]
I am using the Event Handler below for the Enter Key Press Event, it is running when ever any of the keys is pressed. This is not so much a problem when the app. is running, unnecessary yes. It is giving me problems when ever I am Debugging using Breakpoints. How can I change the Handler so it only runs when the Enter Key is Pressed, doing away with the If statement?
Private Sub Form1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles Me.KeyPress If e.KeyChar = Chr(Keys.Enter) Then 'Different code blocks will run here depending on what 'TextBox or Label is selected. End If End Sub
vb.net Module Module1 Public Event Event1(Value as Boolean)End Module
I want to be able to handle this event from different forms. This is what I tried to do...
vb.net Public Class Form1 Private Sub Event1Handler(Value As Boolean) Handles WindowsApplication1.Event1 End SubEnd Class
But I get a squiggly line under WindowsApplication1 that says Handles clause requires a WithEvents variable defined in the containing type or one of its base types. I tried to swap Module1 in, but same thing. I tried without anything in front of Event1, but still nothing.
