Unable to update item in tree!

[Gerard10 (Gerard Verhaag)]

@Johan Anas

Hello again!

I’m not 100% sure that I’m following your thoughts, but if you edit the underlying Entry and want to get the change reflected in the tree, I would suggest doing something like the following (just as an example):

First, let’s assume you have some kind of Entry with some kind of characteristics:

[code]
private class Entry {

    private String displayable;

    private String nonDisplayable;

    public Entry(String disp, String nonDisp) {
        setDisplayable(disp);
        setNonDisplayable(nonDisp);
    }

    @Override
    public String toString() {
        return displayable;
    }

    public String getDisplayable() {
        return displayable;
    }

    public String getNonDisplayable() {
        return nonDisplayable;
    }

    public void setDisplayable(String displayable) {
        this.displayable = displayable;
    }

    public void setNonDisplayable(String nonDisplayable) {
        this.nonDisplayable = nonDisplayable;
    }

}

[/code]Then, let’s create the tree and container (I’ll comment on what is happening, line by line):

        final Tree tree = new Tree("Tree test");
        final HierarchicalContainer hc = new HierarchicalContainer();

        // Instead of a String, let's use the Entry to be editable instead
        hc.addContainerProperty("entry", Entry.class, null);
        hc.addContainerProperty("somethingElseIfYouWant", String.class, null);

        // We add a few entries with some characteristics:
        final Entry e1 = new Entry("e1 to show", "e1 NEVER");
        // e1 functions as the itemId, (but actually I would myself use something else for identifying the items, like a String)
        hc.addItem(e1);

        Entry e2 = new Entry("e2 to show", "e2 NEVER");
        hc.addItem(e2);
       
        /* First we get the item, using the item identifier, and then getting the property
         * using the propertyId "entry". Here your Entries will reside as defined earlier
         * in the container */
        hc.getItem(e1).getItemProperty("entry").setValue(e1);
        hc.getItem(e2).getItemProperty("entry").setValue(e2);

        tree.setContainerDataSource(hc);

        // These two lines will pick up the toString() from entry as the caption for the items in the tree
        tree.setItemCaptionMode(ItemCaptionMode.PROPERTY);
        tree.setItemCaptionPropertyId("entry");
        someLayout.addComponent(tree);

        // Next I'll create a button with a click listener that edits the selected item in the tree:
        Button b = new Button("Edit selected item");
        b.addClickListener(new Button.ClickListener() {

            @Override
            public void buttonClick(ClickEvent event) {
                // The value (selected item) is an item Id (Entry in our case)
                Object itemIdWhichIsAnEntry = tree.getValue();
                if (itemIdWhichIsAnEntry == null) {
                    return; // In case of no selection in the tree
                }

                /* Here get the item (using the itemId), then get the value for the property for that item
                 * and cast it to an Entry (make sure there are no null values). Now we can modify our Entry
                 */
                ((Entry) tree.getItem(itemIdWhichIsAnEntry)
                        .getItemProperty("entry").getValue())
                        .setDisplayable("Changed the entry");
                /* Since we edit our Entry externally, the container/tree does not make note of that.
                 * This means that we have to make the tree dirty in order to be repainted */
                tree.markAsDirty();
                // tree.set

            }
        });
        someLayout.addComponent(b);

Hi Johan,

Thanks for the example with the added comments! That is really helpful!

Regards,
Gerard