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Javafx - Hide TreeTableRow based on data content

I created a TableTree that contains object of class Component that has a boolean property "selected".
I want to hide the rows from the table where the rows component is not selected.
I tried this:
componentTree.setRowFactory(new Callback<TreeTableView<Component>, TreeTableRow<Component>>() {
#Override
public TreeTableRow<Component> call(TreeTableView<Component> param) {
TreeTableRow<Component> row = new TreeTableRow<Component>() {
#Override
protected void updateItem(Component component, boolean empty) {
if(!empty) {
if (!component.isSelected()) {
setVisible(false);
setManaged(false);
System.out.println("hide");
} else {
setVisible(true);
setManaged(true);
System.out.println("show");
}
}
}
};
return row;
}
});
On system.out I can see a lot of "show" and "hide" messages, but this doesn't affect the table, all rows are shown as before.
Any idea on this topic?
Thanks!

I used eclipse's fx.ui.controls library for the same achieve the same goal before.
<dependency>
<groupId>at.bestsolution.eclipse</groupId>
<artifactId>org.eclipse.fx.ui.controls</artifactId>
<version>2.2.0</version>
</dependency>
The library provides a class: FilterableTreeItem<T> under the tree package. This class was designed to be used in cases like yours. You can provide a Predicate to the root of the tree and the items will get hidden when the value given changes:
// Children
final FilterableTreeItem<Component> childNode1 = new FilterableTreeItem<>(component1);
final FilterableTreeItem<Component> childNode2 = new FilterableTreeItem<>(component2);
final FilterableTreeItem<Component> childNode3 = new FilterableTreeItem<>(component3);
// Root
final FilterableTreeItem<Component> root = new FilterableTreeItem<>(rootComponent);
root.getInternalChildren().setAll(childNode1, childNode2, childNode3);
root.setPredicate((parent, value) -> value.isSelected());
// TreeTableView
final TreeTableView<Component> treeTableView = new TreeTableView<>(root);
Note that you have to use getInternalChildren() to add children and the default getChildren().
FilterableTreeItem<T> also provides a predicateProperty() that you can bind to another property in case you need to update the how items are shown or hidden.
Another advatage of this class is that it shows the whole path up to the root of the items matching that predicate.

How to clear the field after i set ComboBox value as null?

I have a ComboBox called projectRequirementComboBox that is dependent from projectComboBox, from where I get the list to show in the dropdown in projectRequirementComboBox, but I want to do something like: when a user changes the project I want to empty projectRequirementComboBox, to be more clear none of the item will not be selected I am doing this right now but still my projectRequirementComboBox has the old value, I don't know what am I missing .I am using vaadin.version 8.0.7 .
private void refreshProjectRequirementCombobox()
{
List<ProjectRequirement> projectRequirements = new ArrayList<>();
if (projectComboBox.getValue() != null)
{
projectRequirements = projectRequirementService.findCurrentProjectRequirements(projectComboBox.getValue().getProjectId());
}
projectRequirementComboBox.setItems(projectRequirements);
projectRequirementComboBox.setValue(null);
}
private void loadProjectRequirement(Project project)
{
List<ProjectRequirement> projectRequirements = new ArrayList<>();
if (project != null)
{
projectRequirements = projectRequirementService.findCurrentProjectRequirements(project.getProjectId());
}
projectRequirementComboBox.setItems(projectRequirements);
}
I call refreshProjectRequirementCombobox here.
projectComboBox.addValueChangeListener(event ->
{
refreshProjectRequirementCombobox();
loadRejectReason();
});

Normally this should work. I created a minimum example with two ComboBoxes "main" and "dependent". The selection of the dependent ComboBox depends on the selection of the main ComboBox. Therefore there is a ValueChangeListener on the main ComboBox that resets the items and the selected value of the dependent ComboBox. When you start the application you see that the offered items of the dependent ComboBox change and that none of these new items is selected.
I think you have to post more of your code (where do you call refreshProjectRequirementCombobox from?) to see what you are doing different.
Here is my example minimum project code:
#Override
protected void init(VaadinRequest vaadinRequest) {
final VerticalLayout layout = new VerticalLayout();
final ComboBox<String> main = new ComboBox<>();
final ComboBox<String> dependent = new ComboBox<>();
final Map<String, String[]> dependentsByMain = new HashMap<>();
dependentsByMain.put("A", new String[]{"AA", "AB", "AC"});
dependentsByMain.put("B", new String[]{"BA", "BB", "BC"});
dependentsByMain.put("C", new String[]{"CA", "CB", "CC"});
List<String> mainItems = new ArrayList<>(dependentsByMain.keySet());
main.setItems(mainItems);
dependent.setItems(Arrays.asList("Test1", "Test2", "Test3"));
dependent.setValue("Test1");
main.addValueChangeListener((HasValue.ValueChangeListener<String>) valueChangeEvent -> {
if (valueChangeEvent.getValue() != null) {
dependent.setItems(dependentsByMain.get(valueChangeEvent.getValue()));
dependent.setValue(null);
}
});
layout.addComponents(main, dependent);
setContent(layout);
}
UPDATE:
Have a look at Srinivasan Sekar's answer and its comments. This is a bug in the used version (8.0.7) which seems to be fixed in version 8.5 (according to https://github.com/vaadin/framework/issues/9047#issuecomment-437864866). I tried my example code with version 8.7.1 so it works. With version 8.0.7 it doesn't.
So the main solution is to update the used Vaadin version. As a workaround (when unable to upgrade the Vaadin version) you FIRST have to set the ComboBox's value to null and THEN set the new items. So in my example the ValueChangeListener must look like:
main.addValueChangeListener((HasValue.ValueChangeListener<String>) valueChangeEvent -> {
if (valueChangeEvent.getValue() != null) {
dependent.setValue(null);
dependent.setItems(dependentsByMain.get(valueChangeEvent.getValue()));
}
});

There is open issue in Vaadin https://github.com/vaadin/framework/issues/9566 which refers to https://github.com/vaadin/framework/issues/2813
Going through the issue I found that by creating a custom combobox you can fix the issue:
public class ClearableComboBox<T> extends ComboBox<T> {
public ClearableComboBox(String in) {
super(in);
}
protected void setSelectedFromServer(T item) {
String key = itemToKey(item);
T oldSelection = getSelectedItem().orElse(getEmptyValue());
doSetSelectedKey(key);
fireEvent(new SingleSelectionEvent<>(ClearableComboBox.this, oldSelection, false));
}
}
Additionally, make sure to call setValue before calling setItems to clear items.
cmb.setValue(null);
cmb.setItems(aEmptyCollection);

How to re-instantiate a Part Class From Menu Handler?

I am new to Eclipse RCP and I am working on an application (Eclipse 4), I have multiple parts within I display data from different sources. I would like to add a menu that displays a Dialog that offers the possibility to select dynamically the data sources that the user wants. When the options are selected I would like to re-instantiate the Part's class using the options as parameters and refresh the view. Is that possible ?
My Part's createComposite method :
#PostConstruct
public void createComposite(Composite parent) {
Composite composite = new Composite(parent, SWT.EMBEDDED);
parent_C = parent;
Frame frame_1 = SWT_AWT.new_Frame(composite);
JPanel mainPanel = new JPanel();
BorderLayout layout = new BorderLayout();
mainPanel.setLayout(layout);
/* Layout Definition */
}
I would like to add another parameter to the createComposite Method that indicates the options :
#PostConstruct
public void createComposite(Composite parent, String[] options) {
/*Code Here*/
}
The Value of the String array changes when the user validate the options from the Menu. When the users validate his options the part's class should be called with the new options.
Is there any way to do this ? Thank You

To do this you need to get the values in the IEclipseContext of the part being created. One way to do this is to subscribe to the UIEvents.Context.TOPIC_CONTEXT event and modify the new part's context in that event.
#Inject
IEventBroker eventBroker;
eventBroker.subscribe(UIEvents.Context.TOPIC_CONTEXT, this::handleContextEvent);
private void handleContextEvent(Event event)
{
Object origin = event.getProperty(UIEvents.EventTags.ELEMENT);
if (!(origin instanceof MPart))
return;
MPart part = (MPart)origin;
// TODO check this is the MPart you want
Object context = event.getProperty(UIEvents.EventTags.NEW_VALUE);
if (!(context instanceof IEclipseContext))
return;
IEclipseContext newContext = (IEclipseContext)context;
newContext.set("nameForOptions", .... options ....);
}
I have used a name for the options here so you would use #Named:
#PostConstruct
public void createComposite(Composite parent, #Named("nameForOptions") String[] options)

Instead of recreating the entire part again, it will be easier to refresh of re-create the content inside the part itself. That should be possible by either disposing the content of the part and recreate the content again under that container, or by refresh mechanism of any table/table viewer.

Java - JCheckBox Filters Against a List

I have a List, that included JPA Entity objects of a certain type. Their reference String values are displayed in a JList for the user to see.
I want my user to be able to select filters as JCheckBoxes in the UI such as 'only from Client x', or 'only of Type x' and dynamically filter the Entity List.
I had thought to just keep a copy of static List completeList; and static List filteredList; and then just run individual filter methods each time a new filter is selected in the UI to update filteredList, which would work fine until you have to un-select a single filter and leave the others selected (at which point it all falls apart).
Every situation I think through fall apart at one point or another, usually when trying to select multiple filters of from one Menu.
An example of my thought pattern that checks all the filters to determine what needs to go in the new JList;
public static void filterList(){
List filteredList = new ArrayList<Job>(StoredDataClass.completeList);
if(clientSmithsCheckBox.isSelected()){
for(Job job : filteredList){
if(!job.getClient.equals(clientSmithsCheckBox.getText())){
filteredList.remove(job);
}
}
}
....... // Check other filters here etc.
if(clientBobAndCoCheckBox.isSelected()){
for(Job job : filteredList){
if(!job.getClient.equals(clientBobAndCoCheckBox.getText())){
filteredList.remove(job);
}
}
}
Even if clientBobAndCoCheckBox is selected, no jobs with that client will show in the final list, because we already removed them all because another client was already selected. Now, we could add to the list instead but we would face similar problems of having add stuff that shouldn't be there etc.
This is obviously possible, because this type of filtering system is common practice (example, excel). Although this is more of a design question, how can I achieve this?

Here's a short (and raw!) example of how you could organize your logic. It's in the context of SwingX (which supports sorting/filtering of a JList just the same way as a JTable) because I'm lazy - but you can apply it to your own environment easily.
Think of your criteria as a collection of filters which can be on or off, and then combine them with OR (if one or more is selected) or turn off if none is selected. The sole "trick" is to evaluate all of the checkboxes' states wheneven one of them is changed:
final JXList list = new JXList(new DefaultComboBoxModel(Locale.getAvailableLocales()));
list.setAutoCreateRowSorter(true);
final List<RowFilter> filters = new ArrayList<>();
filters.add(new MyRowFilter("de"));
filters.add(new MyRowFilter("ar"));
final List<JCheckBox> boxes = new ArrayList<>();
ActionListener l = new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
List<RowFilter<Object, Object>> orCandidates = new ArrayList<>();
for (int i = 0; i < boxes.size(); i++) {
if (boxes.get(i).isSelected())
orCandidates.add(filters.get(i));
}
RowFilter<Object, Object> or = orCandidates.isEmpty() ? null :
RowFilter.orFilter(orCandidates);
list.setRowFilter(or);
}
};
JCheckBox first = new JCheckBox("de");
first.addActionListener(l);
boxes.add(first);
JCheckBox second = new JCheckBox("ar");
second.addActionListener(l);
boxes.add(second);
JComponent content = new JPanel();
content.add(new JScrollPane(list));
for (JCheckBox box : boxes) {
content.add(box);
}
showInFrame(content, "filters");
// just for completeness, the custom RowFilter
public static class MyRowFilter extends RowFilter {
private String text;
public MyRowFilter(String text) {
this.text = text;
}
#Override
public boolean include(Entry entry) {
Locale locale = (Locale) entry.getValue(0);
return locale.getLanguage().contains(text);
}
}

Updating a Wicket WebMarkupContainer

Inside my Wicket webpage, I have a WebMarkupContainer which contains a ListView:
notifications = new ArrayList<Notification>(...);
ListView listView = new ListView("notification", notifications) {
#Override
protected void populateItem(ListItem item) {
...
}
};
container = new WebMarkupContainer("container");
container.setOutputMarkupId(true);
container.add(listView);
this.add(container);
The WebMarkupContainer is in place in order to let me dynamically update the list of items shown to the user onscreen. This is possible when the user clicks on a link or by adding the container to incoming AjaxRequestTarget.
Now I'm required to update the list without having an Ajax request:
public void refresh() {
List<Notification> newNotifications = ...
notifications.addAll(0, newNotifications);
}
This method is called in a run-time environment and the list of notifications, which is a private field of my webpage (same one as last code), will contain new objects. I want these new items displayed to the user. Is it possible to update (or re-render) the container?
I'm new to Wicket so if you have a better way to achieve the same results, I would appreciate if you could share it with me.

You would have to do it on a timer. Use AjaxSelfUpdatingTimerBehavior to do so. Just set some sensible duration and add your container to target in 'onTimer()' method.
EDIT:
If your 'refresh()' function is only called when new notifications appear, you could set a flag on your page (define boolean variable on page and change it to true when new notification appears and to false once listView is refreshed). Then you can set short duration on the behavior and 'onTimer()' would look something like that:
onTimer(AjaxRequestTarget target) {
if(newNotifications) {
target.add(container);
newNotifications = false;
}
}
And refresh
public void refresh() {
List<Notification> newNotifications = ...
notifications.addAll(0, newNotifications);
newNotifiactions = true;
}
That way container won't be refreshed too often (which might cause strange effects) and will refresh every time new notification appears.