I'm attempting to create a simple menu user control just as outlined here. The attached code results in an "Object reference not set to an instance of an object" error, but I can't figure out why.
<%@ Master Language="VB" CodeFile="MySite.master.vb" Inherits="MySite" %>
<%@ Register src="Controls/Menu.ascx" tagname="Menu" tagprefix="my" %>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
[Code]...
I've created a custom control that I insert into my window with the following code
Code:
<controls:ListExpander Text="Class Diagrams"></controls:ListExpander>
The control in question contains several subcontrols, among others, a list. How can create the setup, so I can specify items that should be added to the list?
Code:
<controls:ListExpander Text="Class Diagrams">
<SomeItem>data<SomeItem>
<SomeItem>data<SomeItem>
<SomeItem>data<SomeItem>
<SomeItem>data<SomeItem>
</controls:ListExpander>
In which case the SomeItem objects should be added to the list in the ListExpander:
Code:
<ListBox Name="lstItems" Background="LightGray">
<ListBox.Items>
// Items should go here
</ListBox.Items>
</ListBox>
I'm quite new to WPF, but I suppose it's something along the lines of creating a dependency collection on ListExpander that takes object of the type SomeItem? I simply want to be able to give the control a few arguments which it can translate into items in the listbox contained within the the control.
Is it possible to create a user control with a list of custom class type property? If it is, how can I? The issue is that, in designer mode the property is not displayed in property window. I can add the list on markup but when i switch to the designer mode it gives an error which is 'The user control does not have a public property named BookList'.
View 1 RepliesI recently downloaded VB 2010 Express so i am quite new to the language, but i have worked with dark basic, which seems to b very similar.Anyway, my problem is that i cannot seem to correctly set out my array of a custom type/class. i am trying to create two arrays, one of available entities and another of selected entities of which the user selects the entities to be dealt with in irrelevant ways. i have creates a button (called test) which adds some entities to the available list and all the entities come back the same value but they shouldnt be as you'll c in the code. i have run the step into command a found that "available.item(#).Name = " will change all of the entity's names.As of current i am working with lists as the array kept asking for a 'new' statement but i couldnt figure out where to put it.[code]
View 7 RepliesHow can I create a list (of my custom structure) to hold only unique items? This list should be created from another list.[code]...
View 5 RepliesWe have a ASP.NET web application written in VB.NET where we build content programmatically during the Init event.We make extensive use of user controls, building them on the fly, and I now want to start including SilverLight content.Is there an easy way of embedding a SilverLight application in a control, and then instantiating the whole thing in code, in the same way as you'd programmatically add ordinary ASP.NET controls to a page?The SilverLight component itself works fine when added to a page using the <object> tag but I really want to be able to reuse it elsewhere in code.Since I'm expecting use of SilverLight to increase in our application, and the asp:Silverlight control seems now to be deprecated, I'm looking for an alternative way of wrapping the content.
View 1 RepliesI have a text box which I search SQL server which returns to values based on the text I pass the SP and then I want to add to the list box items so here is my code below the DataTable contains the item I want to return in the list, I have used this syntax to populate a Datagrid with no problems.[code]
View 2 RepliesWhat I've done is create a User Control Library (Project) and I've added a single User Control to that project. The control contains a single FlowLayoutPanel, and I created a Property on the control itself to pass the FlowDirection from the Control to its FlowLayoutPanel child.
Build, reference, component appears in the Toolbox and everything works fine, but the property on the control does not appear in the Properties window when I go to edit it at design time.
I have a list view with 2 columns. I want the user to be able to add there own values to the listview and have them save so that they will always stay there.I would also like users to be able to delete specific items from the saved list.
View 21 RepliesI've got a page (aspx) that contains a usercontrol (ascx).On postback of the aspx, I'd like to read some control values in the ascx. So upon reading some good articles, I created an event in my aspx that fires on postback.The event handler is in the ascx, and simply writes the values I'm interested in to the viewstate so that the parent page can read them.The problem is my event handler never gets hit, even though I see the event is raised as I step through the code. So my code bombs when trying to read the viewstate (which is empty)[code]Oh, did I happen to mention I'm dynamically loading the ascx? :)
View 2 RepliesI have a component class that inherits a user control class and i'm trying to inherit from that same class in a new class.public class B inherits class Unfortunately, I get an error pointing to the .g.vb file saying:Base class 'System.Windows.Controls.UserControl' specified for class '...' cannot be different from the base class '...' of one of its other partial types When I swap the "Inherits System.Windows.Controls.UserControl" with inherits from the base class in .vb files the program compiles but when I try to access any of the components I get an error saying "Object reference not set to an instance of an object."Why is it doing this? it's as if the my sub class isn't inheritingUserControl method at all.
View 2 RepliesI have created a custom Server Control and I want to add a description to the properties and events that the control holds. I have looked over the Internet and came up with the following.[code]Unfortunately this does not seem to work in visual studio .net 2008.
View 1 Repliesi have a check list box. i want the user to limit, selecting maximum of three items from the checklistbox. if user select more than that i want a msgbox to prompt.
View 4 RepliesI'm trying to build a dial control as a custom user control in VB.NET. I'm using VS2008.so far I have managed to rotate image using graphics.rotatetransform . however, this rotate everything. Now I have a Bitmap for the dial which should stay stable and another Bitmap for the needle which I need to rotate.so far i've tried this:
Dim gL As Graphics = Graphics.FromImage(bmpLongNeedle)
gL.TranslateTransform(bmpLongNeedle.Width / 2, bmpLongNeedle.Height * 0.74)
gL.RotateTransform(angleLongNeedle)[code].....
As I understand it, the image of the needle should be rotated at angle "angleLongNeedle" although i'm placing the rotated image at 0,0. However, the result is that the Needle doesn't get drawn on the control.
I created a custom user control named "XYZ" and It is avaialble at the toolbox menu in the design mode and I can drag and drop it to a vb.net Windows form. What I really want is to dynamically to add this user control to the Windows form during the Windows form load event. Actually I want to add this user control to a "split container" named "sc_1" on the tab page named "tp_1" on a tab control named "tc_1" on a Windows form. What is teh vb code to add a user control to a Windows form. I am using vs 2005 and dotnetwork v2.0.
View 3 RepliesI made a custom progressbar as a user control. And I have only been working with forms 'n classes. As you all know, when you create a component in class, it gives you the dll file for the custom component or whatever you made so you can use it on any program. On my custom progressbar, I don't know how to get the ocx or dll file so I can use it on my other programs. OR.. if this is even possible lol. If you could help me on this, that'd be great. And I don't know how to make a custom progressbar out of a class, only user control, so if you could teach me how to make a progressbar out of a class, then that'd be awesome too.
View 3 RepliesHow to create custom events for contol. i have created a user control mytextbox & i am showing some properties of textbox & now i want to expose user control events
I am showing Following properties to user
CODE:
How to expose Events
I have created a base class for some user controls, then I created controls that inherit this class. This is so I can CTYPE the inherited controls back to the base class and refer to properties, methods and events in a common interface. The base class declares has some Public Event BLAH(Sender as object, e as EventArgs) declarations. The derived class then has Public Shadows Event BLAH(Sender as object, e as eventargs) declarations. My parent form adds handlers for the BLAH event. When the derived class fires the event, though, it does not get raised to the parent form.
View 1 RepliesI had this new idea for a user control Sliding Bar/Panel. See screenshot. So I quickly whipped it up but I've got this problem that I cannot figure out why it does not work. Because I wanted to make it nice and tidy I desided to use a Class (Header) and created a TypeConverter (HeaderConverter)
Code:
Public Class HeaderConverter : Inherits ExpandableObjectConverter
Protected SortOrder() As String
Public Sub New()
SortOrder = New String() {"Text", "Depth"}
End Sub
[Code] .....
and goes to the RaiseEvent but nothing happens Why?
I know I could put properties on the Container control to access the ctnbutton Control that is embedded into the control but I thought this might be a nicer way.
I have a user control (SomeUserControl), that I am using in a Main Window. I write my application entirely on SomeUserControl, and Main Window is hosting SomeUserControl and nothing else.
Right now I have a shutdown button (in SomeUserControl), that is supposed to close the Main Window. The reason for this is that I do not want anything from SomeUserControl to close the application itself, but to fire an event from SomeUserControl, and Main Window receives it, and Main Window will close the application instead of SomeUserControl.
How do I do it? I am not familiar with the concept of creating and handling custom events, so if someone could explain it in words and in code as an example, I will be very grateful to you!
Edit: Here's my code so far.
(in Window 2)
Public Event CloseApp As EventHandler
Private Sub CancelButton_Click(sender As System.Object, e As System.Windows.RoutedEventArgs) Handles CancelButton.Click
DialogResult = False
[Code]....
I want to close the application when I click cancel in Window 2, but I don't want to do it in such a way that Window 2 closes itself, but by sending some notification to Main Window, and Main Window closes the application.
vs2010 vb.net WPF project
This is an experiment to learn something.
I have a class called logitem
it has a datetime property, and a message as string property
I have declared myLogEntries as List(of logItem)
I have a ListBox.
Ok now what?
I have searched but i am getting lost in all the examples.
I have set the ItemsSource=myLogEntries
I think i need a datatemplate or maybe to specify binding source.
I am doing all this in the wpf form loaded event.
I guess i need a sample code for binding a list of collection to a listbox.
I'm trying to create a custom control that contains a List(Of Panel). I quickly ran into an error about the base class Panel being nonserializable. So I created my own class that inherits from Panel and implemented the ISerializable interface. At the surface, everything appears to work, at least everything at design time. I don't know what would happen if I tried to run the application. Anyway, the errors occur when I try to open a file that contains my custom control. For example, I create a new Windows Form and add my custom control to it. I save the Form and close it.
Then I try to open the form and get the following error: Object of type 'MyTestApplication.SerializablePanel[]' cannot be converted to type 'MyTestApplication.SerializablePanel[]'.
I don't know what I'm doing wrong? I've opened the XML file to see what it's actually writing, and read the header notes about using binary base64 serialization. I think that's what I'm using, but I'm not sure.
Below is the code for the class SerializablePanel:
Imports System.Runtime.Serialization
Imports System.ComponentModel
<Serializable()> _
[CODE]...
I'm new to custom server controls and I'm hoping to use them to build various 'modules' for different sites I build to cut down on duplicate code.
I'm familiar with custom user controls in which I can create an .ascx & .ascx.vb file which can then be imported into an .aspx page and used freely.
However, with custom server controls I cannot find a way of using markup/html code. Is this possible at all or must all code be created programmatically?
I want to understand N-tier architecture like when to use and so on.Also I would like to know about user control and custom control.
View 4 RepliesI'm developing a program with a team in Visual Basic 2010.
What i wanna do is to create a textbox (inherits from textbox) with additional one property called MDIStatusInformation which is used to display a tooltip text in a status bar at main MDI form.
When i use this tag <Browsable(True)> _, the control property not list anything there.
I need a way to have 3 colums of checkboxes inside a checkedlistbox. I know i could do it with a panel, labels and checkboxes. But having them all in the control would be more convenient. I'm pretty sure there is no direct way of doing this, so i assume i need to create a user control. If you're not completely sure what i'm trying to create, i'm going for something that looks like this: [URL]
View 1 RepliesI'm trying to use ResolveUrl() to set some paths in the code behind of a custom ASP.NET user control. The user control contains a navigation menu. I'm loading it on a page that's loading a master page.When I call ResolveUrl("~") in my user control it returns "~" instead of the root of the site. When I call it in a page I get the root path as expected. I've stepped through with the debugger and confirmed, ResolveUrl("~") returns "~" in my user control code behind.Is there some other way I should be calling the function in my user control code behind to get the root path of the site?
View 4 RepliesI created a Custom User Control at work using VS Express. It was added to my toolbox and then I added it to my form.When I created another one at my home use VS Pro, I think, it was not added to my toolbox and I'm not sure how to access it.
View 6 Replieswhat i am trying to do is create a custom user control for my WPF forms that is a button with both text and an image. Everything that i have found is using C# and i am using vb.net.
View 4 RepliesI have a custom control and would like the properties to be mandatory (not default) when a programmer codes the control. Is there a good way to do this without throwing exceptions in the program?
View 2 Replies