Windows window and messages

In the Windows desktop program, the main concept is the window, it is all the visible objects on the screen (such as various windows, child windows, control windows, etc.) collectively.

The user interacts with the window with the help of a keyboard or mouse. The user's input to the window is passed to the window as a message, and the window communicates with other windows with the help of the message.

There are three stakeholders involved in Windows message operation: <1> user input (via keyboard or mouse) <2> manipulated Windows <3> operating system

First, when the user enters the window (such as changing the size of the window, moving the window, etc.), the operating system captures the user's input information and encapsulates the message into the message queue of the application. The message processing function of the window then processes the messages in the application message queue. This is the process of Windows message operation.

In fact, when the user enters the window, the operating system captures the input information and uses the information as a parameter to invoke the window's message handler function. In the message processing function, the various responses to the message are processed.

Windows window and messages