Click Handlers for Trees in GXT 3?

问题

I've been looking through GXT3's Tree API for some way to execute an action when I click or double click on a node in a tree, and I can't seem to find anything that would work.

I know TreeGrid has a CellClickHandler and CellDoubleClick handler, but there doesn't seem to be anything similar for Tree. There's the generic addHandler method inherited from Widget but this seems like it would apply to the whole tree, not a specific node.

Is there something I'm overlooking, or a different / better way to do this?

回答1:

use the TreePanel's selection model:

treePanel.getSelectionModel().addSelectionChangedListener(
        new SelectionChangedListener<BaseTreeModel>() {

            @Override
            public void selectionChanged(SelectionChangedEvent<BaseTreeModel> se) {

                BaseTreeModel selectedItem = se.getSelectedItem();

                // implement functionality
            }
        }
);

see the TreePanel API for a reference.

回答2:

Another option is to override Tree's onDoubleClick (or onClick) method:

Tree tree = new Tree<MyModel, String>(store, valueProvider){            
    @Override
    protected void onDoubleClick(Event event) {
        TreeNode<MyModel> node = findNode(event.getEventTarget().<Element> cast());
        Info.display("Double Click", "You double clicked this node!");
        super.onDoubleClick(event);
   }
};

回答3:

Use this for Single Selection

    tree.getSelectionModel().setSelectionMode(SelectionMode.SINGLE);
    tree.getSelectionModel().addSelectionHandler(new SelectionHandler<MenuView.MenuDto>() {

        public void onSelection(SelectionEvent<MenuDto> event) {
            MenuDto mnu = event.getSelectedItem();
            Info.display("Tree Handler", mnu.getDescripcion());
        }
    });

For Multiple Selections

    tree.getSelectionModel().addSelectionChangedHandler(new SelectionChangedHandler<MenuView.MenuDto>() {

        public void onSelectionChanged(SelectionChangedEvent<MenuDto> event) {
            List<MenuDto> mnus = event.getSelection();
            Info.display("Tree Handler", mnus.get(0).getDescripcion());
        }
    });

回答4:

Figured it out.This can be achieved by using the Cell Action Tree, an implementation of which can be found here: http://www.sencha.com/examples/#ExamplePlace:cellactiontree

来源：https://stackoverflow.com/questions/10743869/click-handlers-for-trees-in-gxt-3

标签

event-handling

tree

gxt