User Interface (UI) APIs
Introduction to Windows UI Development
The Windows API provides a comprehensive set of functions for creating rich, interactive user interfaces for Windows applications. This section covers the core components and functions related to window management, control creation, message handling, and graphical rendering.
Core UI Concepts
- Windows and Messages: The fundamental building blocks of a Windows application. Applications interact with the system and with each other by sending and receiving messages.
- Controls: Standard UI elements such as buttons, text boxes, list boxes, and scroll bars that applications can use to gather input from the user.
- Graphics Device Interface (GDI): The subsystem responsible for drawing graphics and text on the screen.
- Windows Messaging Loop: The central mechanism by which an application processes messages from the operating system and user input.
Key API Function Groups
Explore the following categories for specific API functions:
Window Management
CreateWindowEx: Creates an extended window.DestroyWindow: Destroys the specified window.GetMessage: Retrieves messages from the application's message queue.TranslateMessage: Translates virtual-key messages into character messages.DispatchMessage: Dispatches a message to a window procedure.SetWindowText: Sets the text of a specified window.GetWindowText: Copies the text of the specified window's title bar (if it has one) into a buffer.
Control Functions
CreateWindow: Creates a window. (Can also create controls)Button_SetState: Sets the state of a button control.Edit_SetText: Sets the text of an edit control.ListBox_AddString: Adds a string to the list box.
Graphics and Drawing (GDI)
CreateCompatibleDC: Creates a memory device context that is compatible with the specified device.Rectangle: Draws a rectangle.TextOut: Writes a string of characters at the specified location.SelectObject: Selects an object into a specified device context.
User Input
GetCursorPos: Retrieves the position of the mouse cursor, in screen coordinates.SetFocus: Sets the keyboard focus to the specified window.