I don\'t like to use XAML. I prefer to code everything in C#, but I think that I am doing things wrong.
In which cases it is better to use XAML and when do you use C
It seems no answers mentioned an important point yet: https://msdn.microsoft.com/en-us/library/windows/apps/xaml/hh465340.aspx
XAML is just procedural code (only easier)
"The following shows how this XAML could be partially replaced by code written in C# or Visual Basic."
// Initialize the button
Button myButton = new Button();
// Set its properties
myButton.Width = 160;
myButton.Height = 72;
myButton.Content = "Click Me";
// Attach it to the visual tree, specifically as a child of
// a Grid object (named 'ContentPanel') that already exists. In other words, position
// the button in the UI.
ContentPanel.Children.Add(myButton);
If you worked with windows forms for example, you probably remember the windows forms designer generates a .designer.cs file containing code similar to the example from the link above. That kind of declarative code is much better represented in XAML than C#.
For any non-toy application you should ALWAYS prefer XAML to define UI and connect it to logic in a MVVM manner.