Floating, Docking, and Pinning MDI Child Forms
You can programmatically provide the functionality to float, dock, and pin MDI child forms in your own application logic, as follows.
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You can control whether users can invoke an MDI menu on an MDI child form by right‑clicking on the caption of the form. The MDI popup menu can contain the following commands.
Menu Command Action Close Closes the form (the same as clicking the Close button or the Context‑Menu Close command) Close All But This Closes all other MDI children in the current MDI frame except for the current form Close All But Pinned Closes all MDI child forms that are not pinned and have the allowClose property set to true Float Floats the current MDI child form Dock Re‑docks the MDI child form in its MDI frame Pin Toggles the pinned status of an MDI child form The Form class provides the following Boolean primitive type properties, all of which have a default value of false, which means that the MDI menu is not displayed by right‑clicking the MDI child caption:
Property Contains the... showMdiCloseAllButPinnedMenu Close All But Pinned command Close All But This command Close command Dock command Float command showMdiPinMenu Pin command If the value of all of these properties is true, right‑clicking the MDI child caption displays a menu.
These properties are ignored if the form is not an MDI child form. In addition, the Close All But This, Close, and Close All But Pinned commands are ignored if the
The property values can be set at run time and in the JADE Painter.
The Float command is disabled if the form is floating and the Dock command is disabled if the MDI child form is already docked in the MDI frame.
The Form class also provides the Boolean type mdiPinned property, which defaults to false. This property is read‑only at run time, to allow access from your application logic to the pinned status of a form.
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The Form class provides the methods listed in the following table.
Method Description floatMdi Floats an MDI child. It does nothing if the form is already floating or if the form is not an MDI child. dockMdi Docks an MDI child. It does nothing if the form is not floating or if the form is not an MDI child. isMdiFloating Returns true if the MDI child is floating or false if it is docked or it is not an MDI child. -
The Form class provides the event methods listed in the following table.
Event Method Description mdiFloated Called after the user floats an MDI child. Appears in the Form Event Methods list box in the JADE development environment. This event is not called if the floatMdi method is called to float the form. mdiDocked Called after the user docks an MDI child. Appears in the Form Event Methods list box in the JADE development environment. This event is not called if the dockMdi method is called to dock the form.
When floated, an MDI child form is positioned on the screen in the same position, except it is not a child restricted to the MDI frame; for example, it can be dragged to another monitor.
The MDI child form is always on top of the MDI frame. To reposition the form programmatically, set the left and top properties, or use the Window class move method.
When an MDI child form is docked, the position and size of the form is restored to the values it had when it was floated, if the current top‑most MDI child in the MDI frame is not maximized. If the current top-most MDI child in the MDI frame is maximized, the docked form is also maximized.
2020.0.01 and higher
