I have a collection class. Say CellCollection, which contains Cells which contains a collection called Cell.
If we do data binding it binds in linear manner. Like first cell11, cell12, cell13, cell14 then, cell21, cell22, etc.,
[Lets assume the collection size is static and proceed]
I have an ItemTemplate for ListBox, which consists of StackPanel which contains 3 textblocks. What I want is the first textblock to have first "Cells"'s first cell ie, Cell11, followed by the second textblock to have second "Cells"'s first cell Cell21 etc.,
Is it possible to bind the collections using indexes in such a way they will be processes in-parallel.
I dono't how to ask this question. I hope the image would help.
I've create dynamic xaml using xaml reader and assigned it as template for the list box. Everything is fine now :)
Related
I need to write an excel-like grid that can have a lot of cells (400x400). All columns have the same width and all rows the same height. Each cell can contain text or be empty and each cell can have a column and/or row span. I suppose this will never work with the Grid panel and I suppose I will need UI virtualization in both column and row direction.
So my first try was to create a virtualizing grid by deriving from VirtualizingPanel and implement IScrollInfo. This could have "easily" be the solution except that I ran into a problem:
To provide IScrollInfo with the relevant information about scroll size and position and to be able to detemine wich items need to be created (realized) next using the ItemsContainerGenerator, I need to know the column index, row indeox and columnspan for each child item (cell). The only way I can think of to do this is using attach properties. The problem is: I can only read the values of attached properties if the ItemContainer that has them is already realized. So I am in a catch 22 here. To know what to realize I need to realize all items. To provide the data for IScrollInfo I need to realize all items.
So it seems that I am at a dead end with this approach.
Do you have any idea how I could implement a control like this or know how I could reslove the above problem?
It strikes me that you may not need to instanciate the UI elements themselves- you can very easily have a collection of DependencyObject-derived viewmodels, each of which has the WidthProperty and HeightProperty set (and possibly bound to the equivalent Width and Height properties of the visible cell UI element, once those are created).
Storing 160,000 (400x400) class instances shouldn't be a problem, especially if you are able to index into the set using row and column.
I have a strange problem with a listbox. I added only the listbox and a button which adds items to the listbox. If I click an item in the listbox it seems to have some strange multi selection mode on or something... i recorded a short screen cast, see for your self:
http://www.youtube.com/watch?v=zV4424ipNEA
any ideas whats wrong?
That is a known issue, as all those strings are the same the selection gets confused because they all are essentially the same object. If you create two identical strings in .NET it does not necessarily create a new one but may reuse the first instance, i am not an expert on this though.
Either wrap the strings in a class (make them the Content of a ListBoxItem for example) or make sure the values are unique.
I have a custom data structure that is pretty much a list of string arrays that I want to display in a (virtual) datagrid in WPF. All the examples of binding I have seen have been to objects with known properties such as a Colors object with a Blue and Red property.
My data is being populated from a SQL query and returns an unknown number of columns.
How can I bind to this type of structure?
(I don't want to use something like ObservableCollection for performance reasons: my data is going to be static so I don't need INotifyPropertyChanged)
See the following question: How to populate a WPF grid based on a 2-dimensional array
If you're only interested in displaying your 2d data then the answer from Jobi Joy will get it done using a Grid.
If you also want to be able to edit the data then you can use a control I created a while back for this purpose called DataGrid2D which subclasses DataGrid
To use it, just add a reference to DataGrid2DLibrary.dll, add this namespace
xmlns:dg2d="clr-namespace:DataGrid2DLibrary;assembly=DataGrid2DLibrary"
and then bind it to your List<string[]> like this
<dg2d:DataGrid2D ItemsSource2D="{Binding ListStringArrayProperty}"/>
DataGrid2D Library
DataGrid2D Source
Greetings to all and sorry for my English!
I have a ListBox, it's ItemsSource = myClientsList.DefaultView. The Items of ListBox have a template (ControlTemplate), that is defined in a in a separate resource file.
Every Item contains a little TextBlock's, Text -property of each have a binding to fields of my Object myClientsList.
I need to add in a this item template more TexBlock's and each of them must have binding to fields of another my class myOrdersList. - (So I wish to view on each line of ListBox information from different tables of my database - this is a question).
Problem in that that ListBox's ItemsSource have a link to object myClientsList and I cann't set myOrderList to ItemSource of same ListBox. So i must find a way to specify TextBlock.DataContext wich inside ControlTemplate or how it's possible to solve this problem in another way?
p.s. I'm a new in .Net and WPF and probably have a mistakes in my explanation - sorry for it.
It sounds like you have a DataGrid type of display and want to add more columns in order to display the order information for a given client. If this is the case, you are going to have to do a couple of things. First, you will need to create a composite object that stores information for both entities into a single object (so each row of your control has all the data it needs to display). Secondly, I would recommend using an actual DataGrid control to display rows instead of templating a ListBoxItem. The ListView with a GridView built into the framework isn't great, so I would recommend the WPFToolkit's DataGrid for a free option.
There are two issues here, if I've understood the question: how do you create a single collection containing both Clients and Orders, and how do you display Clients and Orders in different ways within the same ListBox?
Regarding the first, you can do this using a CompositeCollection.
Regarding the second, define two DataTemplates instead of a ControlTemplate. As the key of each DataTemplate, use the type of the object it is going to present e.g.
<DataTemplate x:Key="{x:Type local:Client}">
Alternatively, use ItemsControl.ItemTemplateSelector to explicitly point at different DataTemplates depending on the type of item. Ot if you really have to use ControlTemplates, check out ItemsControl.ItemContainerStyleSelector.
I have a list of string array as input. The array dimension are static for all the list but I can't know the array size until the list is retrieved.
I need to bind the list in a datagrid in Silverlight.
I tried to create columns at runtime, binding each column to a particular array position but cannot find a way.
Have you any idea how to do it?
I could eventually "convert" my list of array in anything else that could be binded in a datagrid?
The idea is to have a sort of 2d Matrix showed inside the datagrid in Silverlight (I think that the problem is similar).
List
column_1 column_2 column_3 .. column_m
string[1,1] string[1,2] string[1,3] .. string[1,m]
string[2,1] string[2,2] string[2,3] .. string[2,m]
string[3,1] string[3,2] string[3,3] .. string[3,m]
....
string[n,1] string[n,2] string[n,3] .. string[n,m]
n is list lenght, m is list column max number.
Any idea is appreciated
I've found two solution to the problem that use the schema in the Denis's answer:
the first one is to use reflection to generate a class at runtime for the binding as suggested in this article (thanks to Vladimir Bodurov). I've tested this solution and I'll try to use it on my project. The only problem right now is that for large collection, the performance are poor. But I hope that someone will fix it in next relese (Silverlight 3 seems to not have fixed this problem, yet)
the second solution will be using some dynamic language for generate data. I don't know if this could be faster or not (probably not) but eventually could help. I will try in the future and use ironpython or ruby to generate classes that will be binded in datagrid.
If anyone have tryed using the second solution or any performance related information about creating classes at runtime, it will be appreciated.
Giorgio
Unfortunately that's not gonna be easy.
Do you have any valid constraints, like the maximum number of columns that is allowed or anything like that?
If you do (let's say you have N column maximum), you might be able to do something by
Having a class that exposes N
properties (named Col1...ColN for
example) that map the content
of the array for one line at column
X
Generating a list of that class,
one instance for each line
Generating the correct number of
column on the fly, binding each
column to property ColX
Binding your DataGrid to that list
That's kind of ugly, but it would work.
If you do not have to rely on the DataGrid, there is a possibility using a UniformGrid. A UniformGrid is a panel that layouts its children in a regular grid (every item has the same width, every item has the same height). You can indicate the number of columns at runtime, and the panel will fit children one after the other up to the number of columns and then continue on another line.
You could bind an ItemsControl to your array, indicating it should use a UniformGrid as its layout panel and indicating a suitable ItemTemplate to render each string.
The second option is much easier, but you will not have the capabilities of the DataGrid like sorting, moving columns, row selection, edition events per row etc.