Fixes#0004478: Active constraint tool blocks sidebar tasks from working.
Many commands are interrupted by the existence of a handler. Rather than having these commands silently cancel, purge the handler if a command executes that does not need it.
When right-clicking on an item in the Constraint Task sidebar, any current operation is cancelled and the FreeCAD selection is synced with the selected items in the constraints QListWidget. This allows all of the menu items in the context menu to function properly: if the selection is not synced, anything that relies on the FreeCAD selection (like Delete) will sillently fail.
`Sketcher_ConstrainBlock` to `Constraint_Block`.
`Sketcher_ConstrainLock` to `Constraint_Lock`, and the corresponding
`_Driven` variant.
Adjust the icons in the taskpanel for the sketcher constraints,
elements, and for the action menu for constraints.
Adjust the icon order in the `Sketcher.qrc` resource file.
The link support means that an object can now appear in more than one
places, and even inside a document different from its own. This patch
adds support for in-place editing, meaning that the object can be edited
at correct place regardless where it is.
See [here](https://git.io/fjPIk) for more info about the relavent APIs.
This patch includes two example of modifications to support in-place
editing. One is the ViewProviderDragger, which simply adds the dragger
node to editing root node by calling
View3DInventorViewer::setupEditingRoot(dragger). The other much more
complex one is ViewProviderSketch which calls setupEditingRoot(0) to
transfer all its children node into editing root. ViewProviderSketch
also includes various modifications to command invocation, because we
can no longer assume the active document is the owner of the editing
object.
This patch also includes necessary modification of the 'Show' module to
support in-place editing.
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The checkboxes enable a constraint to swap virtual space.
If checked the constraint is visible in the selected space and hidden in the other space (Real Space or Virtual Space).
If unchecked the constraint is visible in the other space and hidden in the selected space.
