How to disable next cell focusing after adding new item in datagrid? Please note that I am doing my application in MVVM pattern.
You can’t disable the selection of the next item. It is the intended behavior of the datagrid.
I hope you want a behavior like when user clicks on some row it should be selected and when a new value is added you don’t want the selection to change automatically.
For that the best thing to do is to bind the SelectedInex of the datagrid to some property and then set it manually when the selection changes when a data is updated.
You could also set the required behavior in the setter of SelectedIndex property too.
Actually there are a few way to select items in the DataGrid. It just depends which one works best for the situation
First and most basic is SelectedIndex this will just select the Row at that index in the DataGrid
<DataGrid SelectedIndex="{Binding SelectedIndex}" />
private int _selectedIndex;
public int SelectedIndex
{
get { return _selectedIndex; }
set { _selectedIndex = value; NotifyPropertyChanged("SelectedIndex"); }
}
SelectedIndex = 2;
SelectedItem will select the row that matches the row you set
<DataGrid SelectedItem="{Binding SelectedRow}" />
private DataRow _selectedRow;
public DataRow SelectedRow
{
get { return _selectedRow; }
set { _selectedRow = value; NotifyPropertyChanged("SelectedRow");}
}
SelectedRow = items.First(x => x.whatever == something);
Related
Hi I am making an WPF application and have a problem with a listbox/listview, MVVM is implemented. I am creating a list of a class that is displayed on the listbox and I am editing the items through selecting an item in the listbox. The problem is when I am deleting an item it doesn't trigger onpropertychanged event to the UI, but is however working in the code, the values are right. When I close the window and reopens it then the list is updated, but not directly when the item is deleted, it never triggers onpropertychanged event for some reason.
It does work to just filter the quicknotelist like
quicknotelist = quicknotelist.where(x => x.id != selecteditem.id);
It works only once though and the UI updates however the selecteditem doesn't seem to work properly even though I am declaring
selecteditem = new quicknote() {*values*};
Part of relevant code, I am using INotifyPropertyChanged
private QuickNote selectedNote = new QuickNote(); // weeeeeee
public QuickNote SelectedNote
{
get
{
return selectedNote;
}
set
{
if (SelectedNote != null)
{
selectedNote = value;
OnPropertyChanged("SelectedNote");
EnableEditNoteBox = true;
}
}
}
private List<QuickNote> quickNoteList = new List<QuickNote>();
public List<QuickNote> QuickNoteList
{
get { return quickNoteList; }
set { quickNoteList = value; OnPropertyChanged("QuickNoteList"); }
}
here is the method that deletes the item
private void DeleteNote(object obj)
{
if (SelectedNote != null)
{
QuickNoteList.Remove(SelectedNote);
// I want this to trigger onpropertychanged without using myclasslist = newclasslist; since it messes up selecteditem to null.
}
}
heres the xaml part.
<ListBox
Width="713"
Height="230"
SelectedItem="{Binding SelectedNote, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"
ItemsSource="{Binding QuickNoteList,BindsDirectlyToSource=True, UpdateSourceTrigger=PropertyChanged, Mode=TwoWay}"
DisplayMemberPath="Notes"
Foreground="Black"
ScrollViewer.VerticalScrollBarVisibility="Visible"
ScrollViewer.HorizontalScrollBarVisibility="Disabled"
ScrollViewer.CanContentScroll="False"/>
I'd leave a comment if I could. You should lookup ObservableCollection. I think QuickNoteList should be of this type.
I have a WPF application/MVVM Pattern and it has a combobox and a treeview control.
What I wanted to do is to show the treeview control only when i select an item from the combobox.
For example : I have a Property called SelectedTransactionName
private string _selectedTransactionWsName;
public string SelectedTransactionName
{
set
{
if (_selectedTransactionWsName == value) return;
this._selectedTransactionWsName = value;
InitializaMessageElement();
}
get
{
return this._selectedTransactionWsName;
}
}
my InitializaMessageElement method will show matching transaction name to the selected item. But now I don't want to show the treeview on page load only when i do a select on the combobox.
On page load I want my window to show only the combobox.
Thanks
Your view model can contain a calculated boolean property to which your TreeView binds its Visibility property, e.g:
public bool IsTransactionNameSelected
{
get
{
return !string.IsNullOrEmpty(_selectedTransactionWsName);
}
}
You could then notify property change in the setter of the SelectedTransactionName:
set
{
if (_selectedTransactionWsName == value) return;
this._selectedTransactionWsName = value;
InitializaMessageElement();
this.NotifyOfPropertyChanged(() => this.IsTransactionNameSelected);
}
Then you can bind your TreeView Visibility property using the supplied BooleanToVisibilityConverter:
<TreeView
Visibility="{Binding IsTransactionNameSelected,
Converter={StaticResource BooleanToVisibilityConverter}" ...
In my WPF Caliburn.Micro application, I have a datagrid and a checkbox with a corresponding ModelView bool property. I need to bind the checkbox to one of the datagrid's fields OneWay (which is easy). But also I want to bind the same checkbox to the property OneWayToSource. Could you please tell me how I can do that? I don't see how Multibinding can help here.
Thanks.
I don't know if this is a checkbox per row of the DataGrid, or a checkbox for a row with a particular id or index. Either way, you can use TwoWay binding, which will be the default anyway if your view model property has a getter and setter.
Your view model property should point to the instance of the record that the DataGrid is binding to.
E.g.
View Model
public ObservableCollection<Item> MyGridItems { get; set; }
public MyViewModel()
{
this.MyGridItems = ...
this.MySpecialItem = this.MyGridItems[0];
}
public Item MySpecialItem
{
get { return this.mySpecialItem; }
set { this.mySpecialItem = value; // notify of property change here }
}
View
<CheckBox IsChecked="{Binding MySpecialItem.MyBooleanProperty}" />
i have an combobox and datagrid when user select a data from combobox the grid will be populated according to that using MVVM and entity framework
Advance thanks
In your ViewModel, create a SelectedItem property which notifies on change as so:
private object _selectedItem
public object SelectedItem
{
get
{
return _selectedItem;
}
set
{
_selectedItem = value;
OnPropertyChanged("SelectedItem")
}
}
Bind your SelectedItem property of your combo box to this property.
Then watch for a change on SelectedItem and change your datagrid's source property accordingly.
I have a WPF ComboBox and am using MVVM to bind the ItemsSource and SelectedItem properties. Basically what I want to do is when a user selects a specific item in the combobox, the combobox instead selects a different item.
<ComboBox ItemsSource="{Binding TestComboItemsSource}" SelectedItem="{Binding TestComboItemsSourceSelected}"></ComboBox>
For demo purposes, I also have a button to update the SelectedItem.
<Button Command="{Binding DoStuffCommand}">Do stuff</Button>
I have this in my viewModel:
public ObservableCollection<string> TestComboItemsSource { get; private set; }
public MyConstructor()
{
TestComboItemsSource = new ObservableCollection<string>(new []{ "items", "all", "umbrella", "watch", "coat" });
}
private string _testComboItemsSourceSelected;
public string TestComboItemsSourceSelected
{
get { return _testComboItemsSourceSelected; }
set
{
if (value == "all")
{
TestComboItemsSourceSelected = "items";
return;
}
_testComboItemsSourceSelected = value;
PropertyChanged(this, new PropertyChangedEventArgs(TestComboItemsSourceSelected))
}
}
private ICommand _doStuffCommand;
public ICommand DoStuffCommand
{
get
{
return _doStuffCommand ?? (_doStuffCommand = new RelayCommand(p =>
{
TestComboItemsSourceSelected = "items";
})); }
}
OK, so I want to have the ComboBox select the item "items" whenever the user selects the item "all".
Using the button, I am able to update the combobox's SelectedItem, and I can see this reflected in the UI
I have similar logic to update the viewModel in my setter of the TestComboItemsSourceSelected property. If the user selects "all", instead set the SelectedItem to "items" So code-wise, the viewmodel property gets changed, but this is not reflected in the UI for some reason. Am I missing something? Is there some sort of side-effect of the way I've implemented this?
Well, this is because you change the property while another change is in progress. WPF will not listen to the PropertyChanged event for this property while setting it.
To workaround this, you can "schedule" the new change with the dispatcher, so it will be executed after it is done with the current change:
public string TestComboItemsSourceSelected
{
get { return _testComboItemsSourceSelected; }
set
{
if (value == "all")
{
Application.Current.Dispatcher.BeginInvoke(new Action(() => {
TestComboItemsSourceSelected = "items";
}));
return;
}
_testComboItemsSourceSelected = value;
PropertyChanged(this, new PropertyChangedEventArgs(TestComboItemsSourceSelected))
}
}
The behaviour you are describing seems very weird for me, but if you want a "Select All" feature, the standar way is to create a combobox where items has a CheckBox.
Each item is represented by a small ViewModel (tipically with Id, Name and IsChecked properties), and you manually create a "select all item" that is added first in the ObservableCollection and subscribe to its PropertyChanged in order to set the rest o the items IsChecked property to true.