hey iam doin silvelright 4 app.
I have datagrid with 3 coloums say Name,Age,EmpId,
The datagrid is not binded to itemsource.(Will have no rows intially)
The user can add new rows and finally save the grid on a button click.
At the moment of button click i need to get all data from the datatgrid and pass to WCF..
Is it possible to assign datagrid empty itemsource?if so how?
how do i store these data from datagrid.. collections or datatable??
Could someone help me out ..i am new to this..
please provide example if possible.
(sorry for my bad english)
You have to bind your datagrid to the collection using ItemsSource. Trust me, it will be easier.
Create a class like this:
public class Person
{
public string Name {get;set;}
public int Age {get;set;}
public int EmpId {get;set;}
}
Then, create a ObservableCollection<Person> and bind it to your dataGrid ItemsSource. On a button click, add the code:
myObservableCollection.Add(new Person() { });
this will add a empty row on your grid so you can fill it with some data.
This way you will have a observableCollection with all your data displayed on a dataGrid. You could process/serialize it and send to the server. If you have a specific question about that I suggest you create another question. RIA Services could do this kind of thing easily.
Related
How can I get multiple instances of a usercontrol without the viewmodel being shared? Each usercontrol (and thus viewmodel) should be an instance of its own.
I have read a solution in this question: MVVMLight UserControl View Model-Create new Instance of User control for each view but I cannot get it to work!
I have a listview and a tabcontrol. When I click an item of the listview a new tab must be created with as content the usercontrol which holds information from the selected listitem. The problem is that when selecting multiple items all the items contain the information from the last selected item.
This is my viewmodellocator:
public DossierDetailViewModel DossierDetail
{
get
{
return new DossierDetailViewModel();
}
}
And I call the new usercontrol like this:
DossierDetailViewModel newDossier = new DossierDetailViewModel();
newDossier.TabName = SelectedDossier.Omschrijving;
this.OpenDossiers.Add(newDossier);
Messenger.Default.Send<DTO.Dossier.Dossier>(SelectedDossier, "SetDossier");
EDIT:
Is there no one who can help me or put me in the right direction? :(
The answer of this problem can be found here: https://mvvmlight.codeplex.com/discussions/577555
In a DataGrid view, the blank row add entries is convenient but quickly get's lost when the list is large. Can you change it's default location from the bottom to the top of the DataGrid view?
I've rarely used a DataGrid and know nothing about its ability to add rows, but coming from a WPF/MVVM point of view, you don't need that anyway. Generally in WPF/MVVM, we manipulate data rather than UI controls, so the solution is easy. First we Bind our collection of data (in whatever shape we chose) to the DataGrid.ItemsSource property:
public ObservableCollection<DataItem> SomeDataCollection { get; set; }
...
<DataGrid ItemsSource="{Binding SomeDataCollection}" ... />
Now, if we want to add a new item to the bottom of the DataGrid we can do this in the code behind/view model:
SomeDataCollection.Add(new DataItem());
Then if we want to add a new item to the start of the collection, we can just do this:
SomeDataCollection.Insert(0, new DataItem());
Of course, you'll need to implement the INotifyPropertyChanged interface in your code behind/view model to make this work, but (hopefully) you'll be doing that anyway.
UPDATE >>>
Sorry, I misunderstood you. I found a NewItemPlaceholderPosition Enumeration on MSDN that is used by an ItemCollection.IEditableCollectionView.NewItemPlaceholderPosition Property. Unfortunately, those linked pages don't have an code examples, so I found one in the in wpf datagrid how to get the blank row on top? post here on StackOverflow. From the answer by #woodyiii in that post:
var view = CollectionView.GetDefaultCollectionView(EmployeeList)
as IEditableCollectionView;
if(view!=null)
view.NewItemPlaceholderPosition = NewItemPlaceholderPosition.AtBeginning;
This does mean that you'd have to use a CollectionView to get this to work, but it seems like the only way... the NewItemPlaceholderPosition Enumeration isn't used by anything apart from the various CollectionView classes.
This worked for me:
IEditableCollectionView cv = (IEditableCollectionView)grdSchedule.Items;
cv.NewItemPlaceholderPosition = NewItemPlaceholderPosition.AtBeginning;
Where grdSchedule is the the name of your DataGrid
I have a class that contains data from some model. This class has metadata along with the actual value.
class ServerValue {
public int SomeId {get;}
public int SomeOtherId {get;}
public DateTime LastChanged {get;}
public object Value {get;set;}
// this lets me show the value, but how do i update it from the grid?
public override string ToString(){
return Value.ToString();
}
}
Now I also have a class MyDataTable that derives from DataTable that has all kind of logic. It calls the server, gets a bunch of ServerValues and puts them into Rows and Columns.
Finally I have a WPF DataGrid that I bind to the MyDataTable and the data are displayed, because the DataGrid calls ToString on each ServerValue and gets back the value for display. Hurray so far.
Now, I want to have two way databinding, so input on the grid is written back to the ServerValue. So I want to bind the grid cells to the Value property of the ServerValue instead of the ServerValue itself.
Right now the ServerValue of the DataGrid cell is just replaced with a string. I could work around this and all but I'd to try the elegant route first.
So I have a datatable with a complex type in cells and i want two-way databinding to a specific property of that type.
Is this possible? I've been googling on this and i can't anything on this.
Thanks in advance,
John
What you want is a way to convert back and forth from your object to their text reprenstations.
Define a Converter for your Binding
http://msdn.microsoft.com/en-us/library/system.windows.data.ivalueconverter.aspx
I have a WPF DataGrid with some data. You can add rows through a separate window. The DataContext is the same, a LINQ-to-SQL object. Binding is also the same, I bind the ItemsSource property to a table.
In the other window, when the user clicks on Save, I create a row programmatically and add it using InsertOnSubmit. After that I use the DataContext's SubmitChanges method.
My problem is that the DataGrid isn't updated. If I restart the application I can see the new row, so it's in the database, but I couldn't find a way to refresh the DataGrid.
So far I've tried to use UpdateTarget on the BindingExpression of the DataGrid, but it didn't help. I've also tried dataGrid.Items.Refresh() — same result. How can I fix this?
try datagrid.Items.Refresh() from here http://programmer.wrighton.org/2009/01/wpf-datagrid-items-refresh.html
The reason it's not updating is that LINQ-to-SQL doesn't implement INotifyCollectionChanged, so WPF has no way to tell that the ItemsSource has been updated. The least terrifying way to fix this, is to copy your LINQ-to-SQL results to an ObservableCollection - when you do the Insert, also add to the observable collection. Then you'll see the update.
I ran into same problem and found that best place for ObservableCollection is DataContext. It has some partial methods generated by designer that can be used to update collection. This code works pretty well:
partial class DataClassesDataContext
{
private ObservableCollection<Task> taskCollection;
public ReadOnlyObservableCollection<Task> TaskView { get; private set; }
partial void OnCreated()
{
taskCollection = new ObservableCollection<Task>(Tasks);
TaskView = new ReadOnlyObservableCollection<Task>(taskCollection);
}
partial void InsertTask(Task instance)
{
taskCollection.Add(instance);
this.ExecuteDynamicInsert(instance);
}
partial void DeleteTask(Task instance)
{
taskCollection.Remove(instance);
this.ExecuteDynamicDelete(instance);
}
}
The problem is that you need to refresh your LINQ-to-SQL DataContext. The DataContext's won't properly recognize the new row even after a submit changes. You need to dispose the DataContext you have and create a new one. In most cases DataContext should be used for one short operation and not as a long standing object.
If you have a case when you have to reload a grid in another window , you can simply close that window and invoke it again.
Or just invoke the search code again (usually the search button)> I have solved it in my case like this.
For some reason Items.Refresh() is not working for me.
What did work was to make my underlying collection inherit ObservableCollection and then call its Add method.
((ContactUIObjects)dgrdContacts.ItemsSource).Add(new ContactUIObject(o));
ContactUIObjects is just the grids underlying collection.
I have a whole bunch of code that is dependent on the ComboBox type, and I want to be able to use it on a new UI, but the UI that I want to use it for needs to look like a RadioButton for usability reasons. Is it possible to have a ComboBox control look like a set of RadioButtons?
My suggestion would be to use an ItemsControl with a DataTemplate that would render RadioButtons. To the ItemsControl you'd bind the same thing you're binding to the ComboBox.
One caveat is that you need to set the GroupName of the radio buttons to something that would be the same to the group, so they can be mutually exclusive. Otherwise, if you don't do anything, you'll be able to select more than one RadioButton simultaneously.
You could build a new UserControl that has many of the same methods that the ComboBox class does, but adapt it so that it creates multiple radio boxes instead.
Your question is kinda vague though.
IE create an Items collection on your user control, and when something is added, draw a radio box and resize your control, instead of what a combo box does and just adds a string to the list.
Then all you have to do is find and replace all your references to ComboBox with RadioIFiedComboBox.
Heres some comparison:
ComboBox cb = new ComboBox();
cb.Items.Add("blah");
or
RadioIFiedComboBox cb = new RadioIFiedComboBox();
cb.Items.Add("blah");
and
public class RadioIFiedComboBox : UserControl {
public ObservableCollection<object> Items = new ObservableCollection<object>();
public RadioIFiedComboBox() {
Items.CollectionChanged += new NotifyCollectionChangedEventHandler(YourCollectionChanged);
}
private void YourCollectionChanged(){
//do something here to redraw your controls
}
}
The code above is just an example, you'd have to create all the methods you use in the ComboBox class and create similar functionality.