I wanted to create dynamic tree struture in my application.
There my requirement is When the user selects any tree node
and click insert the child should be inserted below the selected parent. That is working fine. Now the problem is
i am unable to deselect the currently selected tree item in order to change tree item .
I clicked the background of the view and tried to insert
a new tree item, but still it goes to the previously selected tree node as still it highlight as the selected one. How to solve this issue?
If you create a TreeViewer with style SWT.SINGLE then the tree will insist on keeping an item selected unless you explicitly clear the selection.
To clear a selection use:
treeViewer.setSelection(StructuredSelection.EMPTY);
If you use SWT.MULTI as the tree style you can clear the selection with Ctrl+Click
Related
I have a TreeViewer wherein when the user selects a TreeItem and clicks on a button 'Expand', the entire hierarchy under the TreeItem shoul be opened till the last leaf node is found.
I have found an existing method on TreeViewer which would address my requirement i.e
viewer.expandToLevel(item, level);
I have the selected item which I would pass as first argument to the above method, but how do I get the level?
Use the special value AbstractTreeViewer.ALL_LEVELS for this:
viewer.expandToLevel(object, AbstractTreeViewer.ALL_LEVELS);
Note: object is your data model object (from your content provider) not a TreeItem
I have a TreeItem (a Tree with 100+ TreeItems elements).
I want to give the user the ability to hide (or show again) some TreeItems. (So the user will see just the items he care about).
I cant see a property of TreeItem which give me the ability to show or hide.
How can I do it ?
If you want to show/hide any TreeItem in TreeView you should add or remove it:
parentTreeItem.getChildren().remove(treeItem);
...
parentTreeItem.getChildren().add(treeItem);
I have a application which uses a JTree. For each node in the tree, there is a checkbox attached to the node using a customized TreeCellRenderer. When some items of a node are selected i.e not all children of a node are selected using the chechboxes, how do i indicate using the checkbox of the parent node that only a partial list of nodes is selected. For this, i need to draw a little square in the checkbox indicating that it is partially selected.
You can use e.g.
http://www.roseindia.net/javatutorials/tristatecheckbox.shtml or
http://www.javaspecialists.co.za/archive/Issue082.html
I have a jtree and I only want the user to be able to select sibling nodes. If the user selects nodes that aren't siblings, I want the previously selected nodes to be deselected.
The user should also be able to select sibling nodes that aren't contiguous. I was hoping to extend defaulttreeselectionmodel.
Is there a simple way to do this?
Seems like you'll have to play with TreeSelectionModel (which will store current selection state) and TreeSelectionListener. An example algorithm could be the following : when your selection change, if your TreeSelectionListener is not in active mode, it enters into that mode (this is useful as your listener will update selection in some cases, and you don't want crazy cycles, want you ?). Then, it checks selected nodes using TreeSelectionModel#getSelectionPaths(). If this array size is one, only one node is selected and all is OK. If its size si greater than 1, then you'll have to write some code to ensure those nodes are siblings (as an example by ensuring their TreePath are identical except the last part.
I am tryin to make a software in which when clicked on the subnode of a jtree, detecting which node is selected, want to display respective message.
You will need to add a TreeSelectionListener to the model containing your nodes. The event arguments contain data for the node(s) selected.
Here is some example documentation.