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How to create label and dynamically add binding to its content property in WPF

I'm trying to create a label at runtime and connect it's Content property to another TextBox control which is in my UserControl called MyLabelSettings.
This is what I got so far:
Label currCtrl = new Label();
MyLabelSettings currCtrlProperties = new MyLabelSettings();
// Bindings to properties
Binding binding = new Binding();
binding.Source = currCtrlProperties.textBox_Text.Text;
binding.Path = new PropertyPath(Label.VisibilityProperty);
BindingOperations.SetBinding(currCtrl.Content, Label.ContentProperty, binding);
The last row shows an error which I did not figure out how to solve:
The best overloaded method match for 'System.Windows.Data.BindingOperations. SetBinding(System.Windows.DependencyObject, System.Windows.DependencyProperty, System.Windows.Data.BindingBase)' has some invalid arguments
I have in MyLabelSettings the implementation of INotifyPropertyChanged
which has the following code when the TexBox.Text changes
private void TextBox_TextChanged(object sender, TextChangedEventArgs e)
{
InvokePropertyChanged(new PropertyChangedEventArgs("TextChanged"));
}
Is there a better way to bind these 2? Or am I doing something wrong in this one?
Thanks!

The problem is simpler than you realize:
This:
binding.Source = currCtrlProperties.textBox_Text.Text;
binding.Path = new PropertyPath(Label.VisibilityProperty);
BindingOperations.SetBinding(currCtrl.Content, Label.ContentProperty, binding);
Should be this:
//The source must be an object, NOT a property
binding.Source = currCtrlProperties;
//Since the binding source is not a DependencyObject, we using string to find it's property
binding.Path = new PropertyPath("TextToBind");
BindingOperations.SetBinding(currCtrl, Label.ContentProperty, binding);
Before, you were attempting to bind the value to an object's property via a property. Now, you're binding the value to an object's property via an object (:
Notes:
You are attempting to bind the text of a control that exists in an instance of a class you just made.
MyLabelSettings currCtrlProperties = new MyLabelSettings();
I base this assumption off this line:
currCtrlProperties.textBox_Text.Text;
Which appears to contain a text control of some sort. Rather, you want bind the text of a property that exists in an instance of a class you make, not a control.

Setting the Datacontext of a dynamically created control

I have a UserControl (Map) that contains a Canvas control. I am dynamically adding a control (Gate) to this canvas from the code behind.
I want the Gate objects DataContext to be the "Gate" property of the Map's DataContext. This is being done in the code behind.
Binding dataContextBinding = new Binding();
dataContextBinding.RelativeSource = new RelativeSource(RelativeSourceMode.Self);
dataContextBinding.Path = new PropertyPath("DataContext.SelectedLevelModule.Gate");
dataContextBinding.Mode = BindingMode.TwoWay;
dataContextBinding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged;
BindingOperations.SetBinding(gate, DataContextProperty, dataContextBinding);
After this block of code runs, the gate.DateContext is null...
Any ways this can be done? Drawing a blank..
Thanks
Harold

You are setting the property path to DataContext.SelectedLevelModule.Gate. You are then assigning the binding to the DataContextProperty. I think what is happening is that the path is now gate.DataContext.DataContext.SelectedLevelModule.Gate.
Try removing DataContext from your PropertyPath and see if that fixes it. You are already assigning it to the DataContext, you should not have to specify it in the Path.
var dataContextBinding = new Binding();
dataContextBinding.Path = new PropertyPath("SelectedLevelModule.Gate");
BindingOperations.SetBinding(gate, DataContextProperty, dataContextBinding);

Binding a user control text property in code-behind

I'm trying to create a custom control which inherits from a TextBox control. in the constructor of my custom control I need to have the text property bound. this the code I'm using by now.
var binding = new Binding("Name");
binding.Mode = BindingMode.TwoWay;
binding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged;
binding.ValidatesOnDataErrors = true;
SetValue(TextProperty, binding);
I haven't set a source for binding because I want it be the DataContext of the form on which my custom control will be placed however I suppose I'm doing it in a wrong way because when I added on the form I face the error message in xaml which says: "System.Windows.Data.Binding is not a valid value for property text.

Its not good to do in code-behind, hope this answers your question
Binding binding = new Binding();
binding.Path = new PropertyPath("yourPropertyTobeBinded");
binding.Source = sourceObject;
BindingOperations.SetBinding(youTextBox, TextBox.TextProperty, binding);

How to set a binding in Code?

I have the need to set a binding in code.
I can't seem to get it right tho.
This is what i have tried:
XAML:
<TextBox Name="txtText"></TextBox>
Code behind:
Binding myBinding = new Binding("SomeString");
myBinding.Source = ViewModel.SomeString;
myBinding.Mode = BindingMode.TwoWay;
myBinding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged;
BindingOperations.SetBinding(txtText, TextBox.TextProperty, myBinding);
ViewModel:
public string SomeString
{
get
{
return someString;
}
set
{
someString= value;
OnPropertyChanged("SomeString");
}
}
The property is not updating when i set it.
What am i doing wrong?

Replace:
myBinding.Source = ViewModel.SomeString;
with:
myBinding.Source = ViewModel;
Example:
Binding myBinding = new Binding();
myBinding.Source = ViewModel;
myBinding.Path = new PropertyPath("SomeString");
myBinding.Mode = BindingMode.TwoWay;
myBinding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged;
BindingOperations.SetBinding(txtText, TextBox.TextProperty, myBinding);
Your source should be just ViewModel, the .SomeString part is evaluated from the Path (the Path can be set by the constructor or by the Path property).

You need to change source to viewmodel object:
myBinding.Source = viewModelObject;

In addition to the answer of Dyppl, I think it would be nice to place this inside the OnDataContextChanged event:
private void OnDataContextChanged(object sender, DependencyPropertyChangedEventArgs e)
{
// Unforunately we cannot bind from the viewmodel to the code behind so easily, the dependency property is not available in XAML. (for some reason).
// To work around this, we create the binding once we get the viewmodel through the datacontext.
var newViewModel = e.NewValue as MyViewModel;
var executablePathBinding = new Binding
{
Source = newViewModel,
Path = new PropertyPath(nameof(newViewModel.ExecutablePath))
};
BindingOperations.SetBinding(LayoutRoot, ExecutablePathProperty, executablePathBinding);
}
We have also had cases were we just saved the DataContext to a local property and used that to access viewmodel properties. The choice is of course yours, I like this approach because it is more consistent with the rest. You can also add some validation, like null checks. If you actually change your DataContext around, I think it would be nice to also call:
BindingOperations.ClearBinding(myText, TextBlock.TextProperty);
to clear the binding of the old viewmodel (e.oldValue in the event handler).

Example:
DataContext:
class ViewModel
{
public string SomeString
{
get => someString;
set
{
someString = value;
OnPropertyChanged(nameof(SomeString));
}
}
}
Create Binding:
new Binding("SomeString")
{
Mode = BindingMode.TwoWay,
UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged
};

What is the correct way to bind a textbox to an object

Could somebody please take some time to show me a quick example on how to bind a text box to the property of an object from c# code? (I've tried to do it on my own, but i can't seem to get it right.)
Thank you guys. I just spent an hour before i realized how stupid i am ( i was setting the wrong object as the biding source).
Thank you all for your help.

Binding b = new Binding();
b.Source = yourObject;
b.Path = new PropertyPath("YourProperty");
yourTextBox.SetBinding( TextBox.TextProperty, b );
There are a lot of other properties on binding you can set. The above does one-way binding, but you can change that by setting the Mode property.

Binding the TexeBox Text property with the "Name" property in the ViewModel
Binding binding = new Binding("Name");
binding.Source = ViewModel;
binding.Mode = BindingMode.TwoWay;
SomeTextBox.SetBinding(TextBox.TextProperty, binding);