java-gnome
public class TreeModelSort extends TreeModel implements TreeDragSource, TreeSortable
A TreeIter pointing into this TreeModelSort is not valid in the
underlying "child" TreeModel. If you need to change data in the base model,
use convertIterToChildIter().
You need to be careful to use the correct TreeModel for TreeIter pointers you receive in callbacks. The scenario that arises more often is this:
ListStore model;
TreeModelSort sorted;
TreeView view;
TreeSelection selection;
// usual TreeModel setup
model = new ListStore(...);
// then create the sorted one, and use it
sorted = new TreeModelSort(model);
view = new TreeView(sorted);
...
// then, later
selection.connect(new TreeSelection.Changed() {
public void onChanged(TreeSelection source) {
final TreeIter row;
final String str;
row = selection.getSelected();
if (row == null) {
return;
}
str = model.getValue(row, column);
}
}
the problem that arises is that the retrieved TreeIter is not valid
in model. It's a TreeIter in sorted. Your program
will crash if you get this wrong. The fix is simple; change it to use the
correct TreeModel:
...
str = sorted.getValue(row, column);
...
and things will work fine.
You don't normally have need of this class. Both ListStore and TreeStore
implement TreeSortable already, and there are various sorting tools built
into the view side of the TreeView/TreeModel MVC framework, notably
TreeViewColumn's setSortColumn(). If, however, you are using a TreeModelFilter, you
will need to wrap it in one of these to make sorting work normally again.
TreeModel.RowChanged| Constructor and Description |
|---|
TreeModelSort(TreeModel base)
Create a new TreeModelSort, wrapping an existing model.
|
| Modifier and Type | Method and Description |
|---|---|
TreeIter |
convertIterBaseToSort(TreeIter row)
Given a TreeIter obtained from the underying TreeModel, return one that
represents the same row but that will be valid in this TreeModelSort.
|
TreeIter |
convertIterSortToBase(TreeIter row)
Given a TreeIter valid in this TreeModelSort, figure out the
correspnding row in the underlying TreeModel and return a TreeIter that
will be valid there.
|
TreeIter |
convertIterToChildIter(TreeIter row)
Convert a TreeIter pointing into this TreeModelSort into a TreeIter
valid in the underlying base TreeModel that is being proxied.
|
TreePath |
convertPathBaseToSort(TreePath path)
Convert a TreePath identifying a row in the underying TreeModel into
the corresponding locator in this TreeModelSort.
|
TreePath |
convertPathSortToBase(TreePath path)
Convert a TreePath identifying a row in this TreeModelSort into one
that points to the corresponding row in the underying TreeModel.
|
void |
setSortColumn(DataColumn column,
SortType ordering)
Specify the column from your (underlying) data model which will be used
for sorting this TreeModelSort.
|
public TreeModelSort(TreeModel base)
public TreeIter convertIterBaseToSort(TreeIter row)
public TreeIter convertIterSortToBase(TreeIter row)
public TreeIter convertIterToChildIter(TreeIter row)
TODO We need to test the limitations of this, as several people have actually been getting away with not worrying about converting at all, so clearly something isn't quite as expected.
public TreePath convertPathBaseToSort(TreePath path)
If the row location specified by path isn't resolvable in
the underlying TreeModel, null is returned.
public TreePath convertPathSortToBase(TreePath path)
public void setSortColumn(DataColumn column, SortType ordering)
TreeSortableASCENDING or DESCENDING order via the
ordering parameter.setSortColumn in interface TreeSortable