MDI stands for Multiple Document Interface. In an MDI application, more than one document or child window can be opened within a single parent window. This is a common situation in applications such as spreadsheets or word processors - one window, usually called the MDI parent or MDI container, contains many other windows, usually called (MDI) child forms.
MDI interface was designed in the days of Windows 3 (some 10+ years ago) and it was designed with a single type of application in mind: a parent window that hosts multiple instances of the same class of "document" window (just think of you first MS Word). As such it has its flaws, but is still widely used by (Delphi) developers.
To help you start creating MDI application with Delphi, or to empower your existing MDI solutions, I've collected a few tips and tricks every Delphi MDI developer should be aware of.
Delphi MDI Tutorials, Articles, Tips and Tricks:
- Glossary: MDI
- Constructing "Multiple Document Interface" application with Delphi. First steps.
- On ActiveMDIChild and MDI Parent menu
- Create New or Show Already Created Child Form?
- Hiding Minimized MDI Child Forms
- Implementing OnActivate / OnDeactivate for MDI Child Forms
- Remove MDI Child Title Bar
- Avoid New MDI Child Resizing Animation (and Delay) in Delphi MDI Applications
- Storing and Calling an MDI Child Form from a DLL
- Dim Out the Main Form of an Application When Modal Form is Displayed
- Avoid New MDI Child Resizing Animation (and Delay) in Delphi MDI Applications
- Predefined Windows MDI Shortcut Keys - Or "Why CTRL+F4 closes my child form?"

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