Often, there is a requirement that you would want to create only one instance of the class. To put it in other words, you do not want any one to create instance of the class if already created. This is a common requirement in many application designs. So how do we achieve this ?

This can be achieved using the singleton pattern. In this design pattern, we will declare the constructor as a 'Private' one. Private constructor !! Is that possible?

A docking container can attach one or more areas to a screen. You can attach an area to one or more edges of the screen. The original screen is made smaller to attach this docking container. You can re-size the docking container.

Tip: The containers are attached from inside out. This means that when you attach another container, it is attached to the edge of the screen. The 1st container is pushed outwards. You can attach as many containers as you want. However, it is not recommended to attach too many containers in one screen. Generally a docking container is attached to the left of the screen.