WPF - Set Binding In Object Initializer Expression
Aug 14, 2011
For adding some images to a WrapPanel, I'm trying to iterate through a collection. My TileCollection contains instances of a Tile class which has a ImageSource property. I've got it by doing all the stuff step by step - Create a new image 1, assign all the properties, create a bew binding 1, assign binding 1 to image 1, add image 1 to the panel, proceed with image 2, ... tons of code I want to shorten now. Here is what I've got so far:
For Each tile As Tile In TileCollection
MainPanel.Children.Add(New Image With {.Width = 80, .Height = 80, .Margin = New Thickness(10), .SetBinding = New Binding With {.Source = tile, Path = New PropertyPath("ImageSource"), .Mode = BindingMode.Default, .UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged)}})
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1) ."SetBinding" doesn't work in object initializer expression. Is there any workaround?
2) Is there any way to add a handler in object initializer expression, for e.g. capturing mousedown events?
[code] I get this error Name of field or property being initialized in an object initializer must start with '.' How should I write this? Or is there an alternative way of doing this?
I'm trying to bind UI controls to a business object exposed as a property on an ASP.NET page in a null-safe manner.Using the 'If' operator is null-safe, but results in compiler error:
Compiler Error Message: BC30201: Expression expected.Using 'IIf' succeeds, but isn't null-safe. I've tried both the render expression syntax ('<%= %>') binding expression syntax ('<%# %>'), but there was no difference.Can someone explain this inconsistency and perhaps provide an alternative?
Sample code:
This works: <%=IIf(Me.Foo Is Nothing, "", Me.Foo.Id)%> This throws the compiler error: <%=If(Me.Foo Is Nothing, "", Me.Foo.Id)%>
I use objectbinding to display client data in a datagridview. The datagridview also contains a counry-column allowing the user to choose the country of the client.Unfortunately, databinding of comboboxcolumn does not seem to work if an own business class is used. Using a simple collection instead works well.Copy the sample code into a new windows project and the programm runs fine. Then comment and uncomment the two lines with "XXX" and the code will fail. Why and does anybody know how to make the sample code work by using the business object class(variable named "newClientListVariable" in the sample)? [code]
I have user control which has one button. To handle click event of button I have added following code in usercontrol.
Public Sub ChangeClickHandler(ByVal [Delegate] As EventHandler)
[code]....
Now, I want to handle this click event where I call the this usercontrol. I call the usercontrol through reflection so I get the control in a form of object.
Dim button as object button.ChangeClickHandler(AddressOf mymethod), this line gives me error "'AddressOf' expression cannot be converted to 'Object' because 'Object' is not a delegate type."
Im getting some VB.Net Late binding operations cannot be converted to an expression tree. errors, have search here on the site and can only find solutions to the SQL get data code, not to my problem. The error "Late binding operations cannot be converted to an expression tree." At all my x.NAME) lines !? Im new to this so can anyone say me why i get this error..
I currently have a View in MVC where I pass a single set of data to the view. However, I've come across a problem where I am having to use a LINQ query within a For Each loop in the View to pull out additional information from a SQL View of data from another DB.
The error I'm getting is Late binding operations cannot be converted to an expression tree.
The particular snippet I'm encountering the error on is:
I have this piece of code that works very well and gives me the path the user's start menu:[code]This obviously uses late binding. Now say I want to do this in C#, or in VB.NET strict mode, neither of which support this kind of syntax with late binding.
Now I can change the TextBoxes or the object: MyObject.Two = 3 ..the object and TextBoxes are updated in two ways. Now I want to update the whole object: MyObject = New TestClass(3, 4) ...but this doesn't update the TextBoxes.
Is is possible to bind two BindingList<> object to the DataGridView? Both the bindinglist objects are of the same type. I tried binding an array of BindingLit<> object to the grid, but this fails.
I have created a user control in wpf which consists of a textbox and a listview. Now, I want to bind a class object to the list view from the form where I will use this control. So, basically I want to dynamically set the binding for the listview.
I have a problem about button click event and data binding.I have described my problem in the mark as following
Public Class Window1 Private Sub Window_Loaded(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles MyBase.Loaded Dim list_of_name As New List(Of String) list_of_name.Add("John")
Is it possible to bind a button to an object? I have a situation where I create lots of buttons dynamically and add them to a form, each button corresponds to a record in a database table, I want the button to hold all the info in the record without the need to search for the data each time I press it. I've already have the info in the tag property as a delimited string, but the process of extracting the info from the string is not efficient. if I add one new value I have to add the code to extract that info using string manipulation. I would rather have an object that represents the record so I can access each value directly.
am using VS 2005 and VB. However, if I am not using binding navigator, how can I manage the state of an object it is "added" ( or even "deleted") the property setter is only setting the state to "modified". where should i set it to "added" if i were to insert a new object to a database
I've read (or the only book that covers ado 3.5) is Murach ADO 3.5 and throughout the book, the author recommends using object binding so that's what I've been doing. However, I had a chance to look at all the codes for our applications at work, and only datatables are used.Was curious as to the difference/pros and cons between binding to an object, and binding to a table. I guess my real question is which one should I be using, datatable or object binding? Is there a definite answer or does it depends on the situation and what I want to do?
I'm new to programming and am trying to learn how to developed data driven application and was wondering which method is recommended? I know there are some debates out there but most of the books I have recommend using object binding, but it doesn't offer any concrete information on how to implement it. I went to MSDN and most, if not all, the documentations are on dataset. So I guess my questions is, object vs dataset, which do you use?
it's about object binding, yes it's just a simple binding. but i don't know why it won't work.for summary, i will write about what i am doing:
1. i have one solution, and have two project in it. WaitressDataWin and WaitressDataObject
2. inside WaitressDataWin, i have 'waitressdata.vb' . this is my simple form , there are some basic textbox (waitress name, address, phone)
3. inside WaitressDataObject, i have 'waitressDataObj.vb' is where i put my object class, i have WaitressName property, WaitressAddress, and Phone.one of my property is like this, others are same except the name of course.
Private _WaitressName As String ''' <summary> ''' Gets or sets the Waitress Name[code]....
4. i create data source , that is object data source. i add reference so i can add my second project which is WaitressDataObject and set the WaitressDataObj as the data source.now i have datasource with three properties (WaitressName, WaitressAddress, Phone)
5. I bind my textbox, by dragging the WaitressName (in datasource) to my waitressname textbox .. so on to all my properties.., i also get bindingsourcecomponent, WaitressDataObjectBindingSource
6. then I put this code to my form load :
dim wdm = new WaitressDataObj Me.WaitressDataObjectBindingSource.DataSource = wdm
7. done, it should've been worked, but it didn't , i don't know why.. , every time i fill one of my textbox, the properties didn't set the value, i put breakpoint in the 'set' part of all my properties but it never breaks anyway.. (the 'get' part is good, it read my property value when i load the form). so i just had problem in my 'SET' Part.
8. I think i had checked on my variable (word, case sensitive,etc), no problem.
Using VB 2005. I am attempting Object Binding, with a validation class that handles the validation at the object properties. But, it is working fine for strings only. For any numbers and dates fields on the form, if I simply enter and leave the text box without entering any data, the validation doesn't kick in. It does only when the text box is dirty (an empty string ?), if I enter something and erase it (backspace), the errorprovider is not letting go unless I fill in something that conforms to the data type of the text box and says the input is not in the correct format / type. And at this point, the object property is yet to be assigned any value, and hence my validation class is yet to activate and do its job.
I'm having trouble with some Silverlight functionality. My goal is to get some data from the database and display it in my grid. Sounds simple, however, there are 7 columns that are always going to be there. The rest of the columns depends on the account. There could be 2 (called Actions) associated with a certain account, compared to another account that could have 5, and the action names can be completely different. I have successfully been able to return a list of all the possible actions for the given account, and then adding the columns to the grid in the code bihind(VB), and I can bind my data to the grid for all the columns that are already known. The way I store the item's actions, is a Property of type List. My problem is finding a way to iterate through the actions list of the Item object in order to bind those actions to the grid.
VB 2008 .NET 3.5. I have a custom "Shipment" object that contains a list of "ShippingRate" objects. This list of "ShippingRates" is accessible through a property "Shipment.PossibleShippingRates." That property simply returns a copy of the list of "ShippingRate" for that particular Shipment.
My UI layer receives a list of "Shipment" objects from the BLL. This list is databound to a datagridview, and shows details relevant to the Shipment such as Shipping Address, etc.
I want to bind the "Shipment.PossibleShippingRates" property to a combobox, such that when the user changes the grid row, the combobox reflects the "PossibleShippingRates" for that "Shipment."
In addition, I need a way to store the "ShippingRate" they selected from the combobox for later use.
I have tried a few ideas, but none of them work properly.
With the DataGridView I'm used to just populate them with a list of some object, using the DataSource property. Now I want to just display properties from a single object, and I'm a bit confused on how to do it.. The object is updated through an API event, and I want to select some of the properties for displaying in the DataGridView, to look like this:.where "ValueX" is the name of the properties.Now, what would be my options for binding this to the DataGridView, such that property changes are automatically updated. Since an update also must invoke the control, does that mean I must reassign all bindings, or what logic is necessary in this case?
should I bind to an array, arrayList, stringList, dataTable etc? I guess I'm not sure which type of source will allow binding. Or if I should perhaps build the columns and cells of the grid and populate them "one-by-one" to the properties of the object?
I need to bind a textblock.text property to a single element in an observable collection, or array element, and have the text update using the INotifyPropertyChanged or INotifyCollectionChanged, whichever is best.
Most examples describe ways to bind listboxes or other list views to entire collections, but my application needs to update several textblocks on a screen depending on notification of a change in one or more elements of an array.
Is it possible to bind a single textblock to a single array element? Is it possible to get notification of the proper type that will update one or more of the textblocks if any assigned element changes?
Im doing my first project with WinForms, and Im trying to get the DataBinding working. Theres no database in my project, but I'd like to bind some of the TextBoxes to objects' properties. In the other section of this forum (here) I found this line of C# code which does it: textBox2.DataBindings.Add(new Binding("Text", this.myPerson, "LastName"));
my question is can data binding to object properties be set up during design time (without writing code)? If so, how? P.S. I know how I would set up this binding if in WPF, but I'm forced to use WinForms.
Exception Message happens when my splash screen shows: The type initializer for 'App_Name.GlobalThings' threw an exception GlobalThings is not a class, but just a module name (Module Globalthings). I get the error above at run time (.exe) but not during debug.Because I am brand new not only to visual studio and to visual basic, but also to programming, I have no how to figure out what is actually throwing this error since it occurs only at run time.
