| 49 | | |
| | 49 | * Grouping in most applications has the following behavior: |
| | 50 | * Grouping of groups: |
| | 51 | * Grouping some elements creates a group. |
| | 52 | * Grouping some other elements creates another group. |
| | 53 | * Selected the first group and then the second one and grouping them creates one group of the former two. |
| | 54 | * Ungrouping the lastly created group will return back to the state where we have two groups, since it had been created from these two groups. |
| | 55 | * Grouping of groups and elements: |
| | 56 | * If we have a group and several ungrouped elements, select them all and group them, we will end up having a large group of all the elements from the group along with the elements that were previously ungrouped. |
| | 57 | * Ungrouping the former group we will end up having the first group and the ungrouped elements. |
| | 58 | * '''Note: Current design is done on behalf that we group Frames, but it can be changed quickly to support all kinds of page elements.''' |
| | 59 | * For the grouping to behave properly we should define a tree of groups and elements. |
| | 60 | * Define an interface GroupContainer with the following methods: |
| | 61 | * Prop<? extends GroupContainer> parentContainer(), providing the parent GroupContainer of the class implementing it. |
| | 62 | * RwListProp<Group> containers(), all the containers that a class implementing should provide. |
| | 63 | * Define a class Group which will handle grouping and ungrouping of frames. It will implement the GroupContainer. |
| | 64 | * The Page would also implement the GroupContainer interface. |
| | 65 | * The parentContainer of the Group will be a Page. This means that the Group whose parent container is a Page is a root group. It also provides a list of containers that are Groups. The Group class will also contain a list of frames that are grouped in this group. |
| | 66 | * Page will not have a parentContainer. It will be initially set to null. |
| | 67 | * All this will force a parent<=>child relationship that is manually controlled from within the Group class. |
| | 68 | * The Group class should have two static methods which will do exactly what is supposed for grouping of elements: |
| | 69 | * public static Group createGroup(Page page, List<Frame> frames) - which will create a Group of elements and make it the root group (its parent container should be the page). |
| | 70 | * public static void deleteGroup(Group group) - which will ungroup a previously created group. (the examples explained above). |
| | 71 | * There was another design considered => see '''Comments section'''. |
