Develop Reference

How to make a listbox appear on the form at the click of a button?

I'm a university student therefore I'm not sure on everything to do with writing code. If you could provide hints or a bit of help. I have hidden the listbox via the designer. I've tried listbox1.Show under next button event handler. I've tried looking around on the web but I'm getting no where.
Now answered. Thank you

The solution depends on how you've hidden your listbox. If you did set visible property to false, just use listbox1.Visible = true;.
If you used ' Send to back' to hide it behind another control, you can use listbox1.BringToFront(); to set it into the foreground.
See https://msdn.microsoft.com/en-gb/library/system.windows.forms.control.visible.aspx and https://msdn.microsoft.com/en-gb/library/system.windows.forms.control.bringtofront.aspx

Inside Button_Click Event write:
listbox1.Visible = true;

In my opinion, the best way to show/hide controls (in WPF) is to collapse them. This allows the rest of the controls to behave as if the collapsed control does not even exists, until it is made visible, of course.
This would be done like so:
control1.Visibility = Visibility.Collapsed;
control1.Visibility = Visibility.Visible;
If you are using WinForms, controls will not have a collapse option, and the correct way would be as Almansour has said.

Setting ContextMenu Style to 2013

I'm trying to change the default style of the contextmenu to 2013/2015 in my rehosted vs13 application.
The problem occurs in only one designer, everywhere else its the correct one. I've tried to override both the XAML code and the code behind, checked if something else was changing the style, but without anykind of result.
Is there even a way to change the default style? Am I overseeing something?

Okay, after some heavy research/try and error if finally found out what was wrong: I couldnt access the control I wanted to change the ordinary way, so I had to think outside of the box (and ask a collegue for help).
This is the code that works for me, its not pretty, but it deletes the 'standard'-style set by WPF.
var dv = wd.Context.Services.GetService<DesignerView>();
dv.MenuItemStyle = null;
dv.MenuSeparatorStyle = null;
dv.Resources[typeof(ContextMenu)] = new Style(typeof(ContextMenu));
Quick thanks to Glen Thomas for trying to help.

Reset label control in code behind to original XAML?

I have a C# WPF application with a bunch of labels.
When I run my program it does some checks and wether it the check was positive or not it sets it's corrisponding label to green og red.
These changes is done in my .cs file like:
lblCheck14.Foreground = new SolidColorBrush(Colors.Green);
I would like to add a "Reset" button, that reset the application to it's initial start.
How can I easiest implement this?
One way - but I really hope there is a smarter way, is to set them all like:
lblCheck14.Foreground = new SolidColorBrush(Colors.Black);
lblCheck21.Foreground = new SolidColorBrush(Colors.Black);
lblCheck42.Foreground = new SolidColorBrush(Colors.Black);
Etc..
But isn't there a function which I can call that strips away any changes the .cs file have done to the controls in the XAML file? Like make the XAML back to stock?
Sorry for my back explanation. Hope you understand me :)
Best regards

Implement styles. You can have a default style to roll back to when you hit reset.
Take a look at this tutorial if you're unfamiliar with them: http://wpftutorial.net/Styles.html

Do not manipulate UIElements' properties in code. WPF is not winforms. As Yatrix's answer said, implement styles, or even datatemplates and triggers to manipulate different properties of different UIElements acording to some logic (defined in ViewModel or somewhere else). I suggest you to take a look at WPFTutorial.net

C# -- C++ Intellisense textbox

Is there a way to make a textbox control display C++ intelisense just like it would in Visual Studios?

See This Question and this 'DIY Intellisense' Code Project from the top answer. That's in C#, but the same set of controls is accessable through C++.

I assume you are talking about embedding a control in your own app. You could look at Actipro SyntaxEditor. It will color the C++ right out of the box. If you want intelliprompt/sense you will have supply a parser. They have stuff to help you get started.

I gather you are talking about an AutoComplete popup, not actual intellisense.
To do this, set the AutoCompleteMode of the textbox to Suggest (or SuggestAppend) and choose the appropriate AutoCompleteSource
combDogBreeds.AutoCompleteMode = AutoCompleteMode.SuggestAppend;
combDogBreeds.AutoCompleteSource = AutoCompleteSource.ListItems;
string[] validDogBreeds = new[] {"Bull Mastiff", "Bulldog", "Golden Retriever"};
combDogBreeds.Items.AddRange(validDogBreeds);
Or, in the designer:

WPF - FindName Returns null when it should not

FindName is broken for me :(
The object I am looking for is there. I have proof.
Here is the scenario:
ToggleButton button = (ToggleButton)sender;
Popup popup = (Popup)button.FindName("popSelectIteration");
popup is null but not always. Just sometimes. But even when it is set to null the child I am looking for is there.
I put a break point in when it was null and grabbed these two screenshots.
The is where FindName is returning null for "popSelectIteration".
But if you dig into the watch, you see that the child is there.
So what am I missing? Why does FindName not find it? As you can see from the screen shot this is not a timing issue (the FindName watch is null but the direct path is fine).
Is there a better way to find a control?
Side Note: If you are intersted in the XAML for the toggle button in question it can be found in this question: WPF - FrameworkElement - Enumerate all decendents?.
Update: I did some digging to see why this fails some times and other times it works. I have an animation that calls NameScope.SetNameScope((DependencyObject)form, new NameScope()); (Full method code here). Right after that call the FindName starts to fail.
I don't really understand that call. I think I copied and pasted the code. Anyway, I commented it out. But I would love know why this is failing.

I would guess it has to do with the difference between the visual and logical tree. The control is in the logical tree but maybe the template for this control has not been applied yet and therefore FindName won't return anything useful.
You could try to call ApplyTemplate(); on the container first.
This would also explain why it returns something sometimes.

Try
LogicalTreeHelper.FindLogicalNode(button, "popSelectIteration");

Little late to the party (and not actually answer to OP question), but
when you add elements dynamically, they are not findable by FindName.
You need to register them by calling RegisterName.
Example:
string number = GenerateNumber();
Button myButton = new Button();
myButton.Content = number;
myButton.Name = "button_" + number;
RegisterName(myButton.Name, myButton);
Panel.Children.Add(myButton);
object o = Panel.FindName(myButton.Name);
Maybe someone might find this useful.

In my experience, this happens when you add items via code-behind. I've found that you can fool FindName() (or the animation framework) via name scopes. That is, when you create your control, you do
NameScope.GetNameScope(yourContainer).RegisterName("name of your control", yourControlInstance);
For this to work reliably, though, you must make sure that you unregister the name:
NameScope.GetNameScope(yourContainer).UnregisterName("name of your control");
Posting this for future reference.

I have meet the same question now, but I use the method like so:
#region Override - OnApplyTemplate
public override void OnApplyTemplate()
{
base.OnApplyTemplate();
this.PART_ListViewLeft = GetTemplateChild(cPART_ListViewLeft) as ListView;
this.PART_ListViewCenter = GetTemplateChild(cPART_ListViewCenter) as ListView;
this.PART_ListViewRight = GetTemplateChild(cPART_ListViewRight) as ListView;
this.PART_GridViewLeft = GetTemplateChild(cPART_GridViewLeft) as DsxGridView;
this.PART_GridViewCenter = GetTemplateChild(cPART_GridViewCenter) as DsxGridView;
this.PART_GridViewRight = GetTemplateChild(cPART_GridViewRight) as DsxGridView;
if(this.PART_ListViewLeft!=null)
this.PART_ListViewLeft .AlternationCount = this.AlternatingRowBrushes.Count;
if(this.PART_ListViewCenter!=null)
this.PART_ListViewCenter .AlternationCount = this.AlternatingRowBrushes.Count;
if(this.PART_ListViewRight!=null)
this.PART_ListViewRight .AlternationCount = this.AlternatingRowBrushes.Count;
// ApplyTempleted = true;
CreateColumnLayout();
}
#endregion
If the Control is dynamic create and of which or whose container the 'Visibility' is set to hide or Collapsed, then the code this.PART_ListViewLeft = GetTemplateChild(cPART_ListViewLeft) as ListView; will always return null, the reason is that the datatemplete has not yet been applied before OnApplyTemplate being called.

I would suggest to avoid using FindName function, based on my experience, expecially problematic when you try to find something in the DataTemplate applied to some control.
Instead , if it possible (based on your software architecture) declare Popup in XAML and
refer to it like resource or use Binding to set some Model property to it's reference.
Good luck.

Try to use button.FindResource("popSelectIteration")

ellipseStoryboard.Children.Add(myRectAnimation);
containerCanvas.Children.Add(myPath);
After you add register the controls like
RegisterName("TextBlock1", Var_TextBox);
or
RegisterName(myRectAnimation.Name,myRectAnimation);
RegisterName(myPath.Name,myPath);