Null reference Exception in ListView.InsertItem

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  - 1
    - Listview control Is there a way to automatically fill the last column width of a listview control? Tag: Null reference Exception in ListView.InsertItem Tag: 92425
  - 2
    - Interfaces in Framework 2.0 Hi, Is it always a good idea to have a Interface. Does it have any performance issues. I am referring to Framework 2.0 Beta, Visual Basic 2005. John. Tag: Null reference Exception in ListView.InsertItem Tag: 92424
  - 3
    - Drag and Drop an attachment from an Outlook message I have an email that has a file attached to it. If I save the file and drag the file from Windows Explorer to my form, I get a DragDrop event with data type of FileDrop. If I drag the file directly from the opened email, I get a DragDrop event with the data type of TEXT. What is worse, it appears to be a empty text string. The file in question is a .xml and fairly small, so I would even be happy if I could just get the contents of the file as text. Should I be able to receive that file directly from Outlook email and if so, how. Thanks ------------------------------------------- Roy Chastain KMSYS Worldwide, Inc. http://www.kmsys.com Tag: Null reference Exception in ListView.InsertItem Tag: 92423
  - 4
    - Crystal Reports: Setting LineObject.Left throws exception Hi guys I would like to position a line in a crystal report at runtime. I managed to do the same with a field object and a text object, however it does not work with the line object. Using the command: 'myLineObject.Left = 400;' the following exception occurs: ------------------------------------ An unhandled exception of type 'CrystalDecisions.CrystalReports.Engine.InvalidArgumentException' occurred in crystaldecisions.crystalreports.engine.dll Additional information: Error in File C:\myReport.rpt: Invalid object type. -------------------------------------- Note that the LineObject.Left property is according to the documentation not read-only. Do you know how to solve this problem? Thanks in advance for helping me out. Chris Tag: Null reference Exception in ListView.InsertItem Tag: 92420
  - 5
    - Patterns and best practise for model/view/controller separation? Hi all, I have quite some design experience on other platforms and especially with web applications. Now I'm about to design a .NET application and am a little stuck as I am trying to apply my "habits" of separating model, view and controller. Either that is the totally wrong approach or I am not familiar enough with the platform to make it :). By now, I've already written some model classes and test cases. In that simple case, the "controller" is nothing more than the logic that creates the right instances of models, connects them and calls some business methods on them, validating the results. Now as it comes to adding a GUI and responding to user input, I was hoping that there is something like the "blueprints" with J2EE, that is, some patterns as design recommendations on how to sort things out; or maybe you can share your thoughts and experience with me? I'll try to describe the problems I've run into so far; that should make it easier to reply as the question will be less abstract :) For every model, I will have one or more views to display the models. These views are subclasses of System.Windows.Forms.Form. Basically - how to separate controller and view? It seems to me that it's always the Form class that reacts on user input; but maybe that is just because the IDE/designer suggests that? I assume it is possible to move that code to some "controller" class (probably somehow using the properties of the form controls?) - but is that a good idea? Shouldn't I just keep it as suggested? Next, is it right to create a new instance of a certain view class (the form) for every model I want to display? Or should I avoid creating too many instances of the form class - that would mean I should instantiate every form only once and use something like the flyweight pattern to provide the view with the model it is supposed to display? If several form instances are ok and I keep the controller logic in the form class as well, one approach would be to simply pass the form its model in the constructor like: static void Main() { Model m = new Model(); View v = new View(m); // View subclasses System.Windows.Forms.Form Application.Run(v); } The view would then - maybe in an btnOK_Click handler - update the model, maybe like void button1_Click(object sender, System.EventArgs e) { myModel.doSomeBusiness(textBox1.Text); } Is that a good approach? Clearly, what button1_Click does is the job of a controller. One more problem with the "pass model to form/view constructor" approach is when instantiating new models: Sometimes I need to display a form to collect some user input; that user input is necessary for creating the new model instance. Later on, the same view class is supposed to provide the means of manipulating the model again. I feel it's not a good idea let the form be constructed without a model and add another method like "createAModelFromInput()" that would build the "new" model for me. Thus, another way would be to have something like (informal notation) class Controller { newModelUseCase { v = new View() v.display() // extract "pure data" from view here m = new model(data extracted) } updateModelUseCase { m = someModelIAlreadyGot; v = new View() // extract all data from model here // populate v with the data v.display() } } Now that is clearly too much for a controller - the whole "extract data from model and populate view" thing is the view's responsibility. As a side note, with my specific application requirements I would benefit if the whole create new model / update model could be generic. I know that there will be future extensions to my application that will bring new models with appropriate views, so it would be elegant to keep that part of code arbitrary enough to work with such extensions. As to updating the view upon model state changes, that's probably no problem with a standard observer pattern approach where the view might (pherhaps in its constructor) subscribe for model notifications. The only thing I'm a little afraid here is that in the future, threading problems might arise (what if the model changes in a non-GUI thread and does the notification from there?). I'm happy you read until here :) Again, point me to some recommended approaches/patterns/best practices if there are some :) - I found nothing that satisfies me :). Please reply to the group - I will follow things here. Thanks in advance, Matthias Tag: Null reference Exception in ListView.InsertItem Tag: 92417
  - 6
    - DataGridViewButtonColumn.Text doesn't display onLoad Hi I have a DataGridView on a form, and the last column is of type DataGridViewButtonColumn. How do I get the button text ("Edit") of this column (colEditButton) to display on load of the form? At the moment, my button is blank until I edit a cell in the same row :-( Here are the column's current properties: // // colEditButton // this.colEditButton.AutoSizeMode = System.Windows.Forms.DataGridViewAutoSizeColumnMode.None; this.colEditButton.FillWeight = 32.91695F; this.colEditButton.FlatStyle = System.Windows.Forms.FlatStyle.System; this.colEditButton.HeaderText = "Edit Lookup Table"; this.colEditButton.Name = "colEditButton"; this.colEditButton.Resizable = System.Windows.Forms.DataGridViewTriState.False; this.colEditButton.Text = "Edit"; this.colEditButton.ToolTipText = "Edit Lookup Table"; this.colEditButton.UseColumnTextForButtonValue = true; I'm using VS 2005 Beta 2 Thanks! Tag: Null reference Exception in ListView.InsertItem Tag: 92413
  - 7
    - DataBinding to Custom Class breaks after New instance: how to get around this? Hi, I'm having the following situation: - A class clsFournisseur with public property's which raise a MyPropertyChanged-event in the Set-method for each Property. Public Event NomChanged As EventHandler Public Property Nom() As String Get Return m_strNom End Get Set(ByVal Value As String) m_strNom = Value RaiseEvent NomChanged(Me, New EventArgs()) End Set End Property - A Form, with an instance of my clsFournisseur: "Private WithEvents MyEntreprise As New clsFournisseur". - Proprty's of this Myentreprise are bound to controls on the Form: "Me.txtNom.DataBindings.Add("Text", MyEntreprise, "Nom")" When I change the value in my txtNom.Text, the MyEntreprise.Nom-property is changed. When I change the MyEntreprise.Nom, my txtNom.Text is changed. So far so good. BUT: When in my Form I want to use another clsFournisseur, there isn't anymore databinding. I do this like this: - MyEntreprise = New clsFournisseur(intEntrepriseID) or - MyEntreprise = New clsFournisseur() I guess this is normal behaviour because, even when it still has the same name, it isn't the same class anymore. But I still want to have this databinding! And a weird thing: the txtNom.Databindings.Count = 1, so the TextBox thinks there is still the databinding... Does anybody know how I should do this? Am I doing anything wrong? Should I Clear all the DataBindings after echt new instance of a class and put them back? Any help would be really appreciated. Thanks a lot in advance, Pieter PS: I'm using the CTP from august of Visual Studio .NET 2005 Tag: Null reference Exception in ListView.InsertItem Tag: 92399
  - 8
    - Get ALL controls on a Form Hi, Is there actually a way to get ALL the Controls on a Form? While using the ControlCollection, it only returns the Controls that are directly on the Form, not the controls that are on a (TableLayout)Panel etc. I never found something like that, but it just would be nice in my opinion :-) Thanks, Pieter Tag: Null reference Exception in ListView.InsertItem Tag: 92398
  - 9
    - Help file conversion Hi, I want to display help files in my windows application. Please tell me how to display .chm files through my C# code. Thx in advance. Prasad. Tag: Null reference Exception in ListView.InsertItem Tag: 92396
  - 10
    - Scrolling in a list box Hi, I have two list boxes of the same size and the same number of items in them. The number of items is big, so to accommodate them the list boxes display vertical scroll bars. I want to synchronize the vertical scrolling of these two list boxes, so when one of them is scrolled by the user, the other is scrolled as well so they are both at the same scroll position. How can I do this? I looked for some sort of scroll event that would tell me the position of the scroll bar but I could not find anything. There was a similar example in "Programming VB6" by Francesco Balena, but a "Scroll" event is used there, which we dont have in .NET ( at least I cant find it) Thanks Tag: Null reference Exception in ListView.InsertItem Tag: 92392
  - 11
    - Win Forms App Code Generation? I'm new to .NET and somewhat disappointed in the amount of manual work required to get a simple Win Forms database application built. I'm used to working with a development environment called "Clarion" (that I'm guessing you've never heard of), which can take you from data dictionary to fully functioning application (browse, search, reporting, insert, change, delete, etc), with only a few mouse clicks. Leaving me time to spend on the more serious aspects of the application. What's more, the system doesn't abandon you after the code is generated, but handles design changes. Anyway, coming from this environment to .NET leaves me wondering if you guys really do hand-code all your basic database table browse and update forms? Admittedly I've only been playing with Visual Studio 2003 (and C#) for a while, but it seems very time consuming. Surely there is a better way? Let say I gave you a database with 100 tables and said I wanted a Win Forms application with data entry forms and filterable browse lists on all of them, including the relevant parent-child relationships, referential integrity, concurrency chechking, validation "lookups" - the usual bells and whistles. Is the .NET way to sit down for months and hand-code all this? Or am I totally missing something? I've done a web search for code generators and found a couple, but with little experience with .NET it's hard to tell from the trial versions if they fit the bill. Neither seem to handle design changes, but are kind of like complex wizards. Can anyone offer some pointers, links to sites, tools they used and liked, books I should read, or a more appropriate approach to take? Tag: Null reference Exception in ListView.InsertItem Tag: 92391
  - 12
    - Forms and Panels don't respond to help requests? Hello, Why don't forms and panels respond to help requests? I have a basic form showing the Help button in the title bar, a HelpProvider, a panel and a button; and the panel and button are identically configured to show help on the HelpProvider. When I use the Help button and click on the button the .chm is opened; when I click on the panel (or the background of the form), nothing happens at all. In addition, if I add an EventHandler to the HelpRequested handler of the panel, it never gets called either. So is there some magic trick here, is this a bug or some mysterious "feature?" I've tried this with labels and textboxes, comboboxes, pictureboxes, radio buttons, trackbars; all manner of UI controls. Why are panels and forms different? Anyone have some insight or suggestions? Keith Tag: Null reference Exception in ListView.InsertItem Tag: 92388
  - 13
    - UIPAB - OpenFileDialog Hi, After writing several MDI and Forms demo-apps with UIPAB, I'm starting to feel comfortable with the UIPAB. There is, however, (at least) one issue left : according to http://builder.com.com/5100-6374_14-5058410-2.html saving a file should be an independent task. Now, since an OpenFileDialog is not a UserControl nor a Form, how should it be managed by UIPAB ? On the other hand, popping up an OpenFileDialog is so simple, that writing a separate view, controller, task and appropriate configuration seems a bit, well, overwhelming ... ;-) Any suggestion ? All your comments are highly appreciated ! Thanks, Bart Tag: Null reference Exception in ListView.InsertItem Tag: 92383
  - 14
    - ComboBox BindingContext I have 2 ComboBoxes on a form bound to the same DataSet using a New BindingContext for the second one. Both ComboBoxes need to have their SelectedValue bound to a different DataSet . The first one works properly, but the second one will not select any value. I am pretty sure that this has something to do with the New BindingContext used on the second ComboBox, but I can't get around it. Note: The ComboBoxes are supposed to show a list of Employees (children). And the SelectedValue is from the Contacts table. Each Contact record has 2 Employee_ID fields. Any help would be greatly appreciated!! With ComboBox1 .DataSource = ds2 .DisplayMember = "Initials" .ValueMember = "PrimaryKey" End With ComboBox1.DataBindings.Add("SelectedValue", ds1, "ChildPrimaryKey1") With ComboBox2 .BindingContext = New BindingContext .DataSource = ds2 .DisplayMember = "Initials" .ValueMember = "PrimaryKey" End With ComboBox2.DataBindings.Add("SelectedValue", ds1, "ChildPrimaryKey2") Tag: Null reference Exception in ListView.InsertItem Tag: 92381
  - 15
    - Re: Problem with listbox horizontal scrollbar I am having exactly the same problem, made worse by the fact that = MeasureString introduces a very significant slowdown. Can anyone help? Best wishes, Alex. markusszil (anonymous@discussions.microsoft.com) wrote in = microsoft.public.dotnet.general: > Hello all, >=20 > I have a fairly simple listbox into which I add, insert, and remove = strings. >=20 > It has the following property settings: > HorizontalScrollbar - true=20 > HorizontalExtent - 0 > ScrollAlwaysVisible - False >=20 > The problem I am having is that the horizontal scrollbar range doesn't = work right. If I add a string, the first time the sting width exceeds = the control width the bar appears, but it's off by a few pixels so the = last character is truncated. If I add longer items, it doesn't update so = I can't see the end of them. If I insert items, it never updates. Delete = only seems to work if the entire horizontal scrollbar should disappear. >=20 > I ended up writing code (at end of this post) which goes through all = the strings and uses the Graphics.MeasureString method, then sets = HorizontalExtent to the maximum result. It works, but seems very = cumbersome - and I can't find an event which fires when the = Items-collection changes which could simply call this method. Instead, I = need to go through my code and add calls to this at any point the = collection might change. >=20 > Is this a known issue with listboxes or am I doing something dumb. I = can't believe proper scrollbar operation requires added code. >=20 > Any tips appreciated. > Markus >=20 > Here is the code I had to add: >=20 > private void UpdateHorzScroll()=20 > { > Graphics g=3DGraphics.FromHwnd(Handle); > int wid=3D0; > foreach (object obj in MyListBox.Items)=20 > { > int swid=3D(int)(g.MeasureString(obj as string,Font).Width); > if (swid > wid) wid=3Dswid; > } > MyListBox.HorizontalExtent=3Dwid; > } --=20 Address email to user "response" at domain "alexoren" with suffix "com" Tag: Null reference Exception in ListView.InsertItem Tag: 92380
  - 16
    - Adding a control to the end of a panel Hello everyone, I want to make a control similiar to Apples finder. I need to dynamically add ListBox controls to a panel in a way that all new listbox controls left edge is touching the right edge of the previosly added box and the new box's edge is touching the panels far right edge. Any help would be greatly appreciated. Tag: Null reference Exception in ListView.InsertItem Tag: 92378
  - 17
    - datagrid IndexOutOfRangeException I got two datagrids the first is to display what has been retrived by a selectcommand from a dataset. The other dataset is to display data that is "bound" to the selected row in datagrid1. im filling datagrid1 and it works fine, when i select some row from datagrid1 the datagrid2 is filling fine too, but when i edit a cell from dataset2 and cancel the operation and cursor is on some cell, i get the next error: ************** Exception Text ************** System.IndexOutOfRangeException: Index was outside the bounds of the array. at System.Windows.Forms.CurrencyManager.get_Item(Int32 index) at System.Windows.Forms.DataGridColumnStyle.GetColumnValueAtRow(CurrencyManager source, Int32 rowNum) at System.Windows.Forms.DataGridTextBoxColumn.Edit(CurrencyManager source, Int32 rowNum, Rectangle bounds, Boolean readOnly, String instantText, Boolean cellIsVisible) at System.Windows.Forms.DataGrid.Edit(String instantText) at System.Windows.Forms.DataGrid.Edit() at System.Windows.Forms.DataGrid.OnEnter(EventArgs e) at System.Windows.Forms.Control.NotifyEnter() at System.Windows.Forms.ContainerControl.UpdateFocusedControl() Tag: Null reference Exception in ListView.InsertItem Tag: 92375
  - 18
    - Page_Load event gets called twice I currently have an aspx page that contains a datagrid object and every time the page goes through its lifecycle the Page_Load event gets called twice. I've checked my code and I'm not manually calling it anywhere so the server must be doing it. Can anybody tell me why? and is it possible to stop it? Im using if(!IsPostBack) to see it its a reload and both calls are made before the IsPostBack is set to true. Any help would be appreciated. Thanks, Dave Tag: Null reference Exception in ListView.InsertItem Tag: 92372
  - 19
    - How do you format a date in a ComboBox? I have a combobox that displays dates. They display in a long form, but I would like mm/dd/yyyy. If this were a TextBox, then I would use the Format() method of the Binding. The ComboBox is getting bound like this... cbDate.DataSource = theTable cbDate.DisplayMember = "theDate" cbDate.ValueMember = "theDate" How do I control what gets displayed in the ComboBox? Thanks. David Tag: Null reference Exception in ListView.InsertItem Tag: 92370
  - 20
    - Multiple row select on windowsform datagrid with hidden row headers Hi all, Is it possible to implement multiple row selection on a datagrid when you have the row headers hidden? It works as usual holding the CTRL key as long as you are clicking on the row header, but it doesn't work if you click on the row itself... any help would be great Thanks Gav Tag: Null reference Exception in ListView.InsertItem Tag: 92369
  - 21
    - OnPaint of Datagrid Hi all, I cannot remember where I read the article, however I read one that showed me how to overide the paint function of a datagrid so that I could highlight certain cells in different colours. This works great however if I sort the datagrid by a particular column the rows do not get updated so the wrong rows are then coloured! Can i force the datagrid to redraw when it is sorted? Thanks Gav Tag: Null reference Exception in ListView.InsertItem Tag: 92368
  - 22
    - System.Windows.Forms.TextBox and Magtek Credit Card Stripe Reader I am writing a Windows Forms application where I am using a Magtek credit card reader, a "wedge", to read input into a TextBox control. I am trying to process the input in the TextChanged event handler. The problem I am having is that only the first character of input from the card magnetic stripe is captured in the Text property. In fact, when running in the debugger with a breakpoint in the event handler part of the text that is read gets written to the source file! This causes all kinds of problems in the application. I have done this on a Web form using the System.Web.UI.WebControls.TextBox without problem. What, if anything, can I do to capture the input from this device into the Text property of the Windows.Form.TextBox? Any input would be appreciated Thank, EagleRed Tag: Null reference Exception in ListView.InsertItem Tag: 92367
  - 23
    - Display Union query in a datagrid? Hello, Is it possible to display a union query in a datagrid? If so how? If not what alternatives do I have? What I am trying to do... Primarily; I have two tables that contain related information and share similar columns. I want to merge them for reasons of display. Secondarily; I hope to be able to update either table individually - Column content will distinguish for the system which table to update. Is this possible?... how? -- dbuchanan Tag: Null reference Exception in ListView.InsertItem Tag: 92366
  - 24
    - Catching MDI Application Closing I have an MDI application with a number of child windows. In each child window I am catching the Closing event and having the child window decide if it should set cancel to true. The intent here is to ensure that no child window can close while it is in a state where user entered information can be lost. I have just noticed that while the Closing event is caught if I click the X on the child window, it is not caught if I click the X on the MDI parent window. Is there some other event that I am missing here? Thanks, Ron L Tag: Null reference Exception in ListView.InsertItem Tag: 92365
  - 25
    - error with events in html-document in mshtml/axwebrowser? HELP !! When using AXWebroswer in my Windows-Forms app it is impossible to catch all events of the displayed html-document. It only works with a few events. See the following example: //get the IHTMLDocument2 mshtml.IHTMLDocument2 htmlDoc = axWebBrowser1.Document as mshtml.IHTMLDocument2; if ( htmlDoc != null ) { // get the input item elemnet HTMLInputTextElement input = (HTMLInputTextElement) htmlDoc .all.item("id1", null); if ( input != null ) { // register eventhandler ((HTMLInputTextElementEvents2_Event)input).onclick += new HTMLInputTextElementEvents2_onclickEventHandler( this.Text_EventHandler ); } } private bool HTML_EventHandler(mshtml.IHTMLEventObj e) { MessageBox.Show("Alert from the html:text event" ); return true; } It is possible to register the appropriate event handler, but it is never called !!! But it works when i register an event handler for the click-event, see the following example. // register eventhandler ((HTMLInputTextElementEvents2_Event)input).onchange += new HTMLInputTextElementEvents2_onchangeEventHandler( this.Text_EventHandler ); Is there a different and working approach to catch these events? Tag: Null reference Exception in ListView.InsertItem Tag: 92364
- Next
  - 1
    - edit local security policy using vb.Net I need to edit the local security policy of Windows 2000 machines to disable access for the local Administrator account. How can I programmaticly edit the local security policy using vb.Net? I have looked at using Group Policy, but I must specify each machine name before the account name to make it work. Group Policy won't allow me to do that from the server. Is there something that I am missing? Tag: Null reference Exception in ListView.InsertItem Tag: 92362
  - 2
    - Exposing custom collections as datasources for VS in design time... how to do that? Hi all, I have some custom collections (ArrayList of custom Objects) and I want to display them using typical Windows form controls (DataGrid, Combo). What should I do to expose them as valid datasources to these controls? What if I want that these collections work with Visual Studio on design time in order to allow me easy create grid columns on design time? Can you point me to some examples? Thanks in advance Sammy Tag: Null reference Exception in ListView.InsertItem Tag: 92361
  - 3
    - Clear Selection of a listbox Hi, I have couple of listboxes and a couple of combo box on a form. The listboxes are databound. I am trying to clear the selection of the listboxes if they are not selected by using ListBox.ClearSelected() but in vain. The following lines are in the constructor of the form. Listbox.DataSource = myDataSet; Listbox.ClearSelected(). Can anyone please suggest as to how to clear the selection of the listbox if not selected. Thanks in advance. Tag: Null reference Exception in ListView.InsertItem Tag: 92348
  - 4
    - VPN question If i develop a window application in VPN network, can i use the domain account so as tologin the app Tag: Null reference Exception in ListView.InsertItem Tag: 92347
  - 5
    - add row in datagrid Dear all, Can i add row in datagrid after i bind a dataset to the datagrid Tag: Null reference Exception in ListView.InsertItem Tag: 92346
  - 6
    - export to excel Can vb.net export data to excel file and any license requirement? Tag: Null reference Exception in ListView.InsertItem Tag: 92345
  - 7
    - Procedure expects parameter - What am I missing Hello, The error tells me; --------------------------- Procedure 'usp_sequ_sel' expects parameter '@sqfkJob', which was not supplied. --------------------------- But I do supply it!! What am I missing?? Here is my Stored Procdure [usp_sequ_sel] \\ CREATE PROCEDURE dbo.usp_sequ_sel (@sqfkJob char(36)) AS SET NOCOUNT ON; SELECT pkSequId, sqfkJob, sqComponentDescription, sqAction, sqDuration, sqSooOrder, sqSooPrecedent, sqSooDelay, sqSooNote, sqCreatedOn, sqCreatedBy, sqEditedOn, sqEditedBy, sqrowversion FROM tbl050Sequ WHERE (sqfkJob = @sqfkJob) GO // Here is the Variable as defined in f050Sequ \\ Friend Shared _pkJobID As String 'Using a GUID' // This variable is populated in a combobox \\ Me._pkJobID = Me.cboSelectJob.SelectedValue.ToString // Here is the button to load the datagrid. \\ Private Sub btnLoadTasks_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles btnLoadTasks.Click 'Verifies that the variable '_pkJobID' has gotten the value MessageBox.Show("From f050SqOO.vb ~ sqfkJob: " & Me._pkJobID) _dt = _dataSet1.tbl050Sequ 'The dataTable DAL.da050SequFrm.Fill(_dt) Me.DataGrid1.DataSource = _dt End Sub // Here is the command located in DataAccess.vb runs the stored procedure. \\ With cmd050Sequ_sel .CommandType = CommandType.StoredProcedure .CommandText = "usp_sequ_sel" .Connection = sqlConn With cmd050Sequ_sel.Parameters .Add(New SqlParameter("@RETURN_VALUE", SqlDbType.Int, 4, _ ParameterDirection.ReturnValue, False, CType(0, Byte), _ CType(0, Byte), "", DataRowVersion.Current, Nothing)) 'The line just below fails '.Add("@sqfkJob", SqlDbType.Text).Value = f050SqOO._pkJobID 'The line just below succeds .Add("@sqfkJob", SqlDbType.Text).Value = _ "18713191-e116-4d92-8cc2-c2d4e8c34fdb" End With End With // I use this same scenario in many other forms. For some reason I cannot see what is different here. f050SqOO._pkJobID seems not to be getting the value in DataAccess.vb Help me see the problem. thank you, dbuchanan Tag: Null reference Exception in ListView.InsertItem Tag: 92339
  - 8
    - 4 pane SplitContainer The SplitContainer divides the space in two, either horizontally or vertically. I'd like to divide the space in four. By adding more splitters, the problem is that they don't keep in synch automatically. It'd be nice if when the mouse hovers in the center of the four regions a cross movement icon is displayed, and movement in the two axis is allowed. With the solution of adding more splitters the user is forced to first move in one direction and then in the other one. What do you recommend to achieve this? Thanks. Tag: Null reference Exception in ListView.InsertItem Tag: 92336
  - 9
    - Adding forms into a panel Hi everybody: I am adding several forms into a panel to give MDI appearance to my panel.. Though the forms inside my panel looks fine, I have three problems: 1. The focused form does have the title bar activated (it is gray, like the inactive forms) 2. The only way to bring to front a form is clicking the title bar (in a MDI container, the user can click at anyplace in the form and it gets activated). 3. Cascade, horizontal tile and vertical tile functionality is not provided. Well, the tile and cascade window organization can be implemented, but I do not know how to deal with the focus and mouse problem. Am I doing something wrong? There is another way to implement this functionality? Thank you in advance Ernesto Tag: Null reference Exception in ListView.InsertItem Tag: 92332
  - 10
    - MDI Child Controls If I have a second form that is a mdichild, let's say frm2 and I want to update a textbox control pragmatically... In my MDI parent, I open 5 instances Dim f as new frm2 private sub OpenForm() for i = 0 to 4 f = new frm2 f.mdiparent = me f.show end sub Now, from my parent, I want to update a textbox1 in the active mdi child, how can I? When I just try f.textbox1.text = "some text" it updates the control on the last handle created. I tried finding the active child but couldn't determine how to go from there after I got it. Any help and links would be great. Regards, Brian Tag: Null reference Exception in ListView.InsertItem Tag: 92325
  - 11
    - Forms are re-locating Hi, I have an application which shows forms on two different independant screens. The Windows desktop is spread across these screens. The forms are all set to manual positioning, and so to show a form on the second screen, I simply set the coordinates to be on the second screen and that is where it goes. It now seems to have developed a problem however: When I trace through what is happening all the coordinates get set correctly, and then I call Show() for the form. When show returns, the forms coordinates have been changed to show it on the first screen. I can't trace into the Show function, as it's part of the framework, but something weird is happening. Has anybody seen this before or got any idea what could be going on? Thankyou in advance. Paul Cheetham. Tag: Null reference Exception in ListView.InsertItem Tag: 92320
  - 12
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I'm getting an intermittant null reference expception in
ListView.InsertItem. Since the top of the call stack is in winforms
code, I am not able to tell what is actually null. Here's the top of
the stack:

System.NullReferenceException: Object reference not set to an instance
of an object.
at System.Windows.Forms.ListView.InsertItem(Int32 displayIndex,
ListViewItem item)
at System.Windows.Forms.ListViewItemCollection.Add(ListViewItem
value)

Has anyone experienced this before? Any ideas on what might be going
on here?

thanks for any help!

Top

Re: Null reference Exception in ListView.InsertItem by Atul

Atul
Tue Sep 20 23:09:24 CDT 2005

Most probably, the ListViewItem object being passed to InsertItem is null.

-Atul, Sky Software http://www.ssware.com
Shell MegaPack For ActiveX & .Net - Windows Explorer Like Shell UI Controls

"nlaunceford NO SPAM gmail DOT com" <nlaunceford@gmail.com> wrote in message
news:1127237058.450390.10700@g14g2000cwa.googlegroups.com...
> I'm getting an intermittant null reference expception in
> ListView.InsertItem. Since the top of the call stack is in winforms
> code, I am not able to tell what is actually null. Here's the top of
> the stack:
>
> System.NullReferenceException: Object reference not set to an instance
> of an object.
> at System.Windows.Forms.ListView.InsertItem(Int32 displayIndex,
> ListViewItem item)
> at System.Windows.Forms.ListViewItemCollection.Add(ListViewItem
> value)
>
> Has anyone experienced this before? Any ideas on what might be going
> on here?
>
> thanks for any help!
>

Top