Windows UI Controls API Reference

This section provides comprehensive documentation for the various User Interface (UI) controls available in the Windows API. These controls form the building blocks for creating interactive and user-friendly applications on the Windows platform.

Overview of UI Controls

Windows UI controls, also known as common controls, are reusable components that standardize the appearance and behavior of applications. They offer a consistent user experience and simplify development by abstracting complex UI logic.

Key categories include:

  • Standard Controls: Basic elements like buttons, edit boxes, and labels.
  • Common Controls: More advanced controls like list views, tree views, and progress bars, typically managed by the Common Control Library (ComCtl32.dll).
  • Custom Controls: Controls developed by third parties or custom-built to meet specific application needs.

Buttons

Buttons are fundamental interactive elements that trigger an action when clicked. Windows provides several types:

  • Standard Button (BS_PUSHBUTTON): A click-activated button.
  • Checkbox (BS_CHECKBOX): A toggle button with an associated state (checked/unchecked).
  • Radio Button (BS_RADIOBUTTON): A mutually exclusive selection button within a group.
  • Owner-drawn Buttons: Allow for custom drawing of button appearance.

Relevant APIs: CreateWindowEx with class "BUTTON", messages like BM_SETSTATE, BM_GETSTATE.

Learn more about Button Control Styles.

Input Fields

These controls allow users to enter and edit text or numerical data.

  • Edit Control (EDIT): For single-line or multi-line text input. Supports various styles for read-only, password fields, etc.
  • Rich Edit Control: For rich text formatting (fonts, colors, paragraphs).
  • Spin Control (UPDOWN): A pair of buttons to increment or decrement a value, often associated with an edit control.

Relevant APIs: CreateWindowEx with classes "EDIT", "RICHEDIT", "msctls_updown32". Messages like EM_GETTEXT, EM_SETTEXT, UDM_SETRANGE.

Lists and Dropdowns

Controls for displaying and selecting items from a collection.

  • List Box (LISTBOX): Displays a list of strings, allowing single or multiple selections.
  • Combo Box (COMBOBOX): Combines a list box with an edit control, offering a dropdown list of choices.
  • List View (SysListView32): Displays data in a tabular format with columns, supporting various view modes (list, details, report).
  • Tree View (SysTreeView32): Displays hierarchical data in a tree structure.

Relevant APIs: CreateWindowEx with classes "LISTBOX", "COMBOBOX", "SysListView32", "SysTreeView32". Messages like LB_ADDSTRING, CB_GETCURSEL, LVM_INSERTITEM, TCM_INSERTITEM.

Explore the Common Control Library (ComCtl32.dll) for more details.

Dialogs and Windows

While not strictly controls, dialog boxes and custom windows are essential UI containers. Standard dialogs provide common functionalities.

  • Message Boxes: For displaying simple messages and getting user confirmation.
  • File Dialogs: For selecting files and folders (Open, Save As).
  • Color Dialog: For selecting colors.
  • Font Dialog: For selecting fonts.
  • Property Sheets (Tabbed Dialogs): Organize content across multiple pages.

Relevant APIs: Functions like MessageBox, GetOpenFileName, ChooseColor, ChooseFont, CreatePropertySheetPage.

Feedback Controls

Controls that provide visual feedback to the user about ongoing processes or states.

  • Progress Bar (msctls_progress32): Indicates the progress of a long operation.
  • Trackbar (Slider) (msctls_trackbar32): Allows selection of a value within a continuous range.
  • Hot Key Control: For assigning keyboard shortcuts.

Relevant APIs: CreateWindowEx with classes "msctls_progress32", "msctls_trackbar32". Messages like PBM_SETPOS, TBM_SETRANGE.

Best Practices for UI Controls

  • Accessibility: Ensure controls are accessible to users with disabilities (e.g., keyboard navigation, screen reader support).
  • Responsiveness: Design interfaces that adapt well to different screen sizes and resolutions.
  • Consistency: Follow platform guidelines for UI design to provide a familiar experience.
  • Performance: Optimize the use of controls, especially in list views and tree views, to maintain application responsiveness.