Introduction

Dyalog APL supports dockable Forms, SubForms, CoolBands and ToolControls.

If an object is dockable, the user may drag it to a different position within the same container, drag it out of its current container and drop it onto a different container, or drop it onto the desktop as a free-floating window. An undocked object can subsequently be redocked in its original container or in another.

For example, a SubForm can be dragged from one Form and docked into another. Or a CoolBand can be dragged out of its CoolBar and turned into a top-level Form on the desktop.

With the exception of ToolControls, when a dockable object is docked or undocked, the full Name and Type of the object change according to the following table.

	Parent Object
Dockable Object	Form F1	SubForm F1.S1	CoolBar F1.CB1	Root (.)
Form F2	SubForm F1.F2	SubForm F1.S1.F2	CoolForm F1.CB1.F2	Form F2
Form F1.F2	SubForm F1.F2	SubForm F1.S1.F2	CoolForm F1.CB1.F2	Form F1.F2
SubForm F2.S2	SubForm F1.F2	SubForm F1.S1.F2	CoolForm F1.CB1.F2	Form S2
CoolForm F2.CB2.C2	SubForm F1.C2	SubForm F1.S1.C2	CoolForm F1.CB1.C2	Form C2

For example, a top-level Form F2 when docked in another top-level Form F1, becomes a SubForm named F2.F1.

Similarly, a CoolBand named F2.CB2.C2 when dragged from its CoolBar F2.CB2 and dropped over the desktop, becomes a top-level Form named C2.

Notice how the node name of the object remains the same, but its full pathname changes as it is moved from one parent object to another.

When an object changes Type in this way, the values of all its properties for its original Type are remembered, and these are automatically restored when the object reverts back to its original Type. Since an object can change Type between Form, SubForm, and CoolBand, it follows that there are effectively 3 different sets of properties associated with the object. However, only one set of properties (the set associated with the object's current Type) is visible and accessible (to the programmer) at any one time.