|
Take a look at the sticky at the top on how to ask a question, yours was not a good example and will not get the answer you want. Try reading some of the articles, work through the samples[^] there are plenty out there.
Never underestimate the power of human stupidity
RAH
|
|
|
|
|
So I have this XAML code:
<Window.Resources>
<local:MainViewModel x:Key="ViewModel" />
</Window.Resources>
And this is the XAML for the actual control:
<StackPanel Orientation="Horizontal" Width="897" Margin="5" DataContext="{StaticResource ViewModel}">
<ItemsControl Width="897" ItemsSource="{Binding Intersections}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<WrapPanel Width="897" >
<RadioButton GroupName="Intersections"
Content="{Binding Text}"
IsChecked="{Binding IsChecked, Mode=TwoWay}" Width="150"/>
</WrapPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
In the code behind I have this public class:
Public Class MainViewModel
Sub New()
Intersections.Add(New Insertion() With {.Text = "Item 1"})
Intersections.Add(New Insertion() With {.Text = "Item 2", .IsChecked = True})
Intersections.Add(New Insertion() With {.Text = "Item 3"})
Intersections.Add(New Insertion() With {.Text = "Item 4"})
End Sub
Private _Intersections As New ObjectModel.ObservableCollection(Of Insertion)
Public Property Intersections() As ObjectModel.ObservableCollection(Of Insertion)
Get
Return _Intersections
End Get
Set(ByVal value As ObjectModel.ObservableCollection(Of Insertion))
_Intersections = value
End Set
End Property
Public Class Insertion
Private _Text As String
Public Property Text() As String
Get
Return _Text
End Get
Set(ByVal value As String)
_Text = value
End Set
End Property
Private _IsChecked As Boolean
Public Property IsChecked() As Boolean
Get
Return _IsChecked
End Get
Set(ByVal value As Boolean)
_IsChecked = value
End Set
End Property
End Class
End Class
The problem Im haveing is to get the RadioButtons to be shown Horizantaly, and I cant figure out how to do that. I have tried to set IsItemsHost="True" but Its giving me the error "A panel with IsItemsHost="true" is not nested in an ItemsControl. Panel must be nested in ItemsControl to get and show items.". Either I heave tried to do this in all the wrong places or Im missing some key information here.
To be clear the code works, but its giving me a stack of the RadioButtons, but I want the side by side like a WrapPanel.
The example is taken from here here[^], and I converted it to VB from C#.
modified 17-Sep-12 13:49pm.
|
|
|
|
|
Use ItemsPanelTemplate and put the radio buttons horizontally inside a stack panel.
E.g.
<ItemsControl.ItemTemplate>
<ItemsPanelTemplate>
<StackPanel Orientation='Horizontal' "/>
</ItemsPanelTemplate>
|
|
|
|
|
I tried this:
<StackPanel Orientation="Horizontal" Width="897" Margin="5" DataContext="{StaticResource ViewModel}">
<ItemsControl Width="897" ItemsSource="{Binding Intersections}">
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal">
<RadioButton GroupName="Intersections"
Content="{Binding Text}"
IsChecked="{Binding IsChecked, Mode=TwoWay}" Width="150"/>
</StackPanel>
</ItemsPanelTemplate>
</ItemsControl>
</StackPanel>
But this time it wont build properly with ItemsPanelTemplate, I have seen this on the webbefore also, but couldnt get it to work, Can you?
|
|
|
|
|
I think (though Im not sure), one needs to put the <itempresenter> tag somewhere.
|
|
|
|
|
ITs working now, but its a strange code, and its well over a page long, so I dont think I'll be pasting it here, unless you are really interested 
|
|
|
|
|
Ok Found the answer here[^] . The code that works looked like this:
<StackPanel Orientation="Horizontal" Width="897" Margin="5" DataContext="{StaticResource ViewModel}">
<ItemsControl Width="897" ItemsSource="{Binding Intersections}">
<ItemsControl.Template>
<ControlTemplate>
<WrapPanel Width="{TemplateBinding Width}" Height="{TemplateBinding Height}"
FlowDirection="LeftToRight" IsItemsHost="true">
</WrapPanel>
</ControlTemplate>
</ItemsControl.Template>
<ItemsControl.ItemTemplate>
<DataTemplate>
<WrapPanel Width="120">
<RadioButton GroupName="Intersections" Content="{Binding Text}" IsChecked="{Binding IsChecked, Mode=TwoWay}" Width="150"/>
</WrapPanel>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</StackPanel>
|
|
|
|
|
I have this combobox:
<ComboBox x:Name="cboServerList"
Grid.Row="0"
Grid.Column="1"
Margin="5"
Height="23"
IsEditable="True"
ItemsSource="{Binding Servers}"
SelectedItem="{Binding SelectedServer}"
TextSearch.TextPath="ServerName"
Text="{Binding ServerName}">
<ComboBox.ItemTemplate>
<DataTemplate>
<TextBlock Text="{Binding ServerName}"/>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
Since it's editable, as soon as I start typing the SelectedServer property's setter fires. How can I set it up so that it doesn't fire until the user presses Enter or tabs out?
Thanks
If it's not broken, fix it until it is
|
|
|
|
|
Set the UpdateSourceTrigger of the binding to LostFocus. That won't handle the enter key though. Which is probably ok since the enter key has a different meaning. Dunno why you'd want to do this though. Sounds like an issue with your VM setter being too expensive??
|
|
|
|
|
Thanks for the tip
SledgeHammer01 wrote: Dunno why you'd want to do this though. Sounds like an issue with your VM
setter being too expensive??
Why would you want the property's get to fire on each keystroke?
If it's not broken, fix it until it is
|
|
|
|
|
Kevin Marois wrote: Why would you want the property's get to fire on each keystroke?
Who cares if you update a string 50 times? What do you think happens with WPF controls? If you scroll down a combo box, you'll get a bunch of updates for each item too.
If you are binding to expensive setters, your design is wrong. In your example, it is perfectly fine to update a string property 50 times, but if that is also triggering 50 database updates, then thats an improper design.
You are trying to solve the wrong problem here I think .
|
|
|
|
|
SledgeHammer01 wrote: Who cares if you update a string 50 times?
I care. This is a search field. I don't want the search running after every keystroke. Of course it's bound to a property. How else would you do it?
SledgeHammer01 wrote: If you are binding to expensive setters, your design is wrong. In your example,
it is perfectly fine to update a string property 50 times, but if that is also
triggering 50 database updates, then thats an improper design
This is exactly what I'm trying to avoid. That's why I don't want the setter to execute until the user presses enter. That's a pretty normal requirement.
If it's not broken, fix it until it is
|
|
|
|
|
Ok... I'm confused. There are two ways to do search:
1) a real-time live search (i.e. Google, Internet Explorer, etc)
2) only do the search when the user clicks the OK / search button
For #1, you would do it on every key stroke.
For #2, it depends on how your UI is laid out. Do you have a pop up dialog with an OK button? Or is it something like where you have an edit box in the main window frame?
Irregardless of how you are implementing #2 UI wise, I think you are confusing your property setter with your action trigger. Those should be separate. The "public string SearchText" property should not kick off a search. Since all you should be doing in it is updating the property, its fine to update it 50 times. Then your enter key / ok / search button will send a command to the VM to kick off the search.
The button sending the command portion I'm assuming you already know how to do, for trapping the enter key, all you need to do is use your EventToCommand mapper to map the KeyDown event of the edit box to an ICommand and forward along the eventArgs. In your command handler function, you would simply check if the key pressed was the enter key. All nice and MVVM'y .
|
|
|
|
|
SledgeHammer01 wrote: Ok... I'm confused. There are two ways to do search:
1) a real-time
live search (i.e. Google, Internet Explorer, etc)
2) only do the search when
the user clicks the OK / search button
Ok, well that's just your opinion. I can point out mroe than a few UI designs where search happens when the user types, and also where nothing happens until you press enter. Open up Windows Explorer and type something into the search field. Nothing happens until you press enter. There's no button, becuase it's an extra step. Type, then reach for the mouse. Bad design IMHO. For heads down work, press enter to confim/trigger and action.
At any rate, I'll set the UpdateSourceTrigger of the binding to LostFocus.
If it's not broken, fix it until it is
|
|
|
|
|
Lol... you just described #1 and #2. #2 is trigger based, I thought it was implied that the trigger could be ANYTHING whether it be a button, the enter key, or you stepping on your cats tail. Silly me.
At any rate, I'll let others help you from now on, as you are kind of rude to people who help you for free on thier own time  .
|
|
|
|
|
SledgeHammer01 wrote: At any rate, I'll let others help you from now on, as you are kind of rude to
people who help you for free on thier own time .
Wow, sorry. I didn't mean to be rude. Sorry if I came across that way.
If it's not broken, fix it until it is
|
|
|
|
|
I have previous experience using WinForms and the DataGridView control. I am trying to re-code a previous program using WPF that reads a parts list from a delimited text file and displays results in a DataGrid control.
In WinForms, I was able to assign a tag to the DataGrid row that I used to link individual URLs to our company's HTML-based inventory program. However, I am unsure how to do this (if it's even possible) in WPF. Currently, I read from the text file and load its contents into a List. From there, I filter the List by whatever the user selects, then display the results in a DataGrid control. I want to open up the browser when the user selects a row, but can't figure out how to bind the URL to the row. Is this possible? If so, can someone help point me in the right direction?
Thanks.
|
|
|
|
|
As long as you use data binding to bind your data to the grid, you really don't have much of a problem. Each row will be bound to the original item in the list, so it's simply a matter of reading from your SelectedItem, which will return the real item you are bound to.
|
|
|
|
|
Hi Pete,
Thanks for the response! I am not sure what you are suggesting. I am binding the data from the List into separate columns in my DataGrid. But instead of returning the information in the DataGrid, I want to open a browser window and go to the URL.
It's hard to explain without pictures, but I have a DataGrid with 6 columns. Under column 1, I list a description, with a hyperlink look. I bind the description of the part to that column. When the user clicks on that row, that's when I want to open the browser window. I thought about just using a DataGridHypertextColumn, but every example I could find online used an absolute address (http://exampleaddress.com). I will need to read the address from a textfile database. I suppose I could add another column and bind the URL to its own DataGrid column, but I am trying to avoid that.
Since I can't upload pictures, I have included the code.
private List<addData> LoadCollectionData()
{
List<addData> readData = new List<addData>();
string searchLine = (machineComboBox.SelectedValue.ToString()).ToUpper();
string findLine = searchTextBox.Text.ToUpper();
foreach (string readLine in File.ReadAllLines(path))
{
if (readLine.Contains(searchLine) && readLine.Contains(findLine))
{
string[] myData = readLine.Split('|');
readData.Add(new addData()
{
description = myData[0],
ICN = myData[1],
RIN = myData[2],
indexCode = myData[3],
location = myData[4],
machine = myData[5]
});
webLink = myData[6];
}
}
return readData;
}
And here is the XML:
<DataGridTextColumn Header="Part Name" CanUserResize="True" Width="225" Binding="{Binding description}">
<DataGridTextColumn.ElementStyle>
<Style TargetType="TextBlock">
<Setter Property="FontSize" Value="20"/>
<Setter Property="FontWeight" Value="Black"/>
<Setter Property="TextElement.Foreground" Value="Blue"/>
<Setter Property="TextDecorations" Value="Underline"/>
<Setter Property="TextWrapping" Value="Wrap"/>
<Setter Property="HorizontalAlignment" Value="Stretch"/>
<Setter Property="Cursor" Value="Hand"/>
</Style>
</DataGridTextColumn.ElementStyle>
</DataGridTextColumn>
I apologize for being a little slow in understanding what you have explained so far, but I am very new to WPF and DataGrid seems much more complicated than it was in WinForms.
|
|
|
|
|
Ok, you're missing a bit out here. How do you bind the data to the DataGrid itself? I'd expect to see something like ItemsSource="{Binding MachineInfo}" in the DataGrid definition (replace MachineInfo with whatever collection your data is really in - it should be a public property on the class that you have bound to the view as the DataContext).
I appreciatet these terms may be confusing, but it's a little tricky explaining all of them in a forum post - they are covered more by articles. Let me know if you have any problems with this.
|
|
|
|
|
Hi again Pete,
Sorry it took me so long to respond. I'm actually an Electronics Tech on an oil rig so I got a little busy last night.
My binding was not in the code I provided (sorry!). It was actually in the code-behind, binding to a List collection via a method, so it looked something like this:
partsDataGrid.ItemsSource = LoadCollectionData();
And the method:
private List<addData> LoadCollectionData()
{
List<addData> readData = new List<addData>();
string searchLine = (machineComboBox.SelectedValue.ToString()).ToUpper();
string findLine = searchTextBox.Text.ToUpper();
foreach (string readLine in File.ReadAllLines(path))
{
if (readLine.Contains(searchLine) && readLine.Contains(findLine))
{
string[] myData = readLine.Split('|');
readData.Add(new addData()
{
description = myData[0],
ICN = myData[1],
RIN = myData[2],
indexCode = myData[3],
location = myData[4],
machine = myData[5],
webLink = myData[6]
});
}
}
return readData;
}
From there, I binded the elements of the List to each column of the DataGrid.
I did find a solution to my problem, and it was in the misunderstanding of how a DataGrid actually works (along with how to access a List collection). My bindings were correct for the DataGrid, however, in essence, I wanted to bind two separate pieces of information to one column. As far as I can tell from researching, that is not allowed. And I'm not sure that would be considered good programming if it were.
The solution to my problem was to access the 'webLink' variable in the List separately, and then recall the URL associated with it when I selected the row. The code I used looks something like:
private void partsDataGrid_SelectedCellsChanged(object sender, SelectedCellsChangedEventArgs e)
{
int index = partsDataGrid.SelectedIndex;
if (index < 0)
index = 0;
else
{
string webAddress = ((addData)partsDataGrid.Items[index]).webLink;
}
}
As always, I am grateful for your help and appreciate the fact that more experienced programmers are willing to help others who are not quite as smart as they are...yet!
Thank you for the guidance.
|
|
|
|
|
This is probably an unusual question as I cannot find anything that makes me think that what I want to do is common practice but not doing this causes a memory leak.
The reason for registering a scriptable object is to be able to use the unbeforeunload method (JavaScript) at application exit. This is only needed at a very specific and brief time during the application lifetime after which I would like to cancel the registration of the scriptable object as it only causes to keep the page (this instance) alive in memory for the rest of the app lifetime. Unregistering (removing the key) and re-registering when it is needed again would solve the problem. I just don't know how to do it.
Here is the code :
<pre>Application app = Application.Current;
if (!app.IsRunningOutOfBrowser)
{
HtmlPage.RegisterScriptableObject("Page", this);
}
[ScriptableMemberAttribute]
public string LeaveRequested()
{
//method run before unload
}
[ScriptableMemberAttribute]
public bool PreventLeave()
{
return (bool)PreventLeaveCheckBox.IsChecked;
}</pre>
This works like a dream when it's needed, but it's a nuisance when it's not required.
Thanks for any help in advance.
|
|
|
|
|
You are really posting in the wrong place. People here do not do much with HTML. You need to post on an ASP.NET forum.
|
|
|
|
|
I am using this in a Silverlight 5 project ! So definitely in it's place.
|
|
|
|
|
Yes I see the out of browser reference now.
Basically a WPF developer, so not much help here.
|
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
