Show recent GRASS Databases in the Data tab

[wenzeslaus]

The Data tab shows only the current GRASS (GIS) database (directory). Some users have two or more of these "grassdata" directories, so moving data between then should be possible. For example, r.proj already allows that (dbase option).

The additional databases/directories could be added manually to cover all the cases, but perhaps just putting there n recent ones would suffice to most users.

To avoid some long loading times, maybe only the current database/directory tree should be loaded and the other(s) should be loaded on demand, e.g., with context menu (this may lead to unexpected situations, e.g., with search).

Also useful if the Data tab/data catalog functionality is reused for the startup window.

Depends on:

• #572 Remember recent GIS Data Directory