The context menu is available when working with most ObjectLand windows. As a rule, this menu duplicates some items of the main menu and that is why it is not described separately. However, in some situations context menu operations are the only means to perform some actions. One of these situations is editing (including adding) features. The context menu enables the user to perform successive undoing of changes made in the map in the course of ObjectLand session starting from the last change. It is also possible to redo the canceled changes. Besides, when the system is in the mode of adding or editing features, the context menu contains some other important commands used in editing.
Description of all commands of editing context menu will be provided in the course of describing the operations connected with these commands. Below you may find description of most general commands of context menu which have relation to editing map features.
Undo… This command is present in the context menu not depending on the mode set in the map browser window. If no changes were made with the features of displayed map in the present session this command is disabled. If new features were added, removing and editing the existing features occurred during the session, the command Undo is enabled and the text of this command describes the contents of the last editing operation performed which is subject for undoing (for example, Undo Moving of Area Feature, Undo Adding Vertex and so on). It is not important how the operation was performed – by coordinate editing or using interactive operations. If some editing operations were performed, after undoing the last one the system will offer to undo next to last operation and so on.
The list of performed operations supported by the system usually has some finite length, that is why if there were many operations performed only a limited number of last operations can be canceled. The list of operations is linked with the map, not with a particular theme, that is why the same list is used for all theme browser windows built on the basis of one and the same map. Thus, in one browser window it is possible to undo the operations that were performed in another window with the features of the same map.
Redo… This command is always present in the context menu, however, it remains disabled until undoing at least of one editing operation is performed. After that the operation is activated with clarification text: Redo Removing Vertices, Redo Rotation of Line Feature and so on. In this context the command Redo means performing the operation which was canceled as a result of last performed command Undo, that is, “undo the operation of undoing”.
It should be especially noted that there is no need to return to the mode of editing or adding vertices to perform the operation of undoing or redoing. These operations can be performed in any mode, and the feature being changed should not necessarily be selected.
Delete. The command is present in the menu only in the mode Edit and can be used to remove features as well as individual vertices of the feature being edited. If the submode Editing vertices is turned off, execution of the command Delete will cause removal of all selected features. If this submode is turned on, all marked vertices of the edited feature will be removed. In both cases the warning before removal is not displayed. The same result is achieved after pressing the key Delete.
If there are no selected features in the theme browser window or there are no marked vertices, when the submode Editing vertices is turned on, the command Delete is disabled.
Removing features can be performed in other modes as well (for example, Selection), but the system will request confirmation of the operation. Besides, it is impossible to delete individual vertices of a feature using this method.
Abort Adding. The command is present in the menu in the modes Adding new feature and Adding inner boundary. The command is enabled in the course of performing adding of the feature or inner boundary, its execution results in canceling the adding operation.
Complete Adding. The command is present in the menu in the modes Adding new feature and Adding inner boundary. The command is enabled in the course of adding a feature or inner boundary if sufficient number of vertices (two for a line feature, three – for area one) has been added. Performing this command causes completion of the adding operation.
Show Selected Features. The command is present in the modes Edit, Adding new feature and Adding inner boundary. The command is enabled in the case if there are one or several selected features. If some of these features do not fall into the displayed fragment, the system changes the scale and the center of the fragment so that all selected features fell into this fragment. If all the features were in this fragment before, the command is ignored.
Reset Selected Features. The command is present in the menu in the modes Edit, Adding new feature and Adding inner boundary. The command is enabled in the case if there is one or several features selected for editing. Resetting of feature selection is performed.
 |  |
