JavaFX: CheckBoxTreeItem item not selected when checked - javafx

Question

Before finding out about CheckBoxTreeItem, I used a regular TreeItem, with a ComboBox. The CellFactory had an onAction property which I passed into the CheckBox onAction method. The onAction EventHandler came from the Controller, so when I checked/unchecked that action method in the controller was called. The problem was the TreeItem did not get selected.
Now trying to use CheckBoxTreeItem instead. However I have a few problems with it regarding selection and action.
I need to perform an action when a CheckBox has been checked/unchecked. I want the checkbox to change state when the TreeItem has been selected. I need the TreeItem to be selected when a CheckBox is changed.
1)
Selecting the TreeItem does not change the selected state of the CheckBox. I had to write an onMousePressed action to do that.
#FXML public void performSelection() {
TreeItem<Mine> selectedItem = treeView.getSelectionModel().getSelectedItem();
boolean selected = ((CheckBoxTreeItem<Mine>) selectedItem).isSelected();
((CheckBoxTreeItem<Mine>) selectedItem).setSelected(!selected);
}
However, when a CheckBox on the TreeItem is checked/unchecked, that TreeItem is not selected. Is not that the point of CheckBoxTreeItem?
2)
I have created a ChangeListener that listens to the state of the CheckBoxTreeItem selectedProperty. This listener is registered on each items in the tree. It is the only way I can create an action to do some work on checked/unchecked.
However, checking an TreeItem, since it does not select the TreeItem I cannot access it with tree.getSelectionModel().getSelectedItem() in the listener. A CheckBox action where I cannot access the TreeItem data of that CheckBox's item is pointless. If I select a TreeItem it stays on that TreeItem, and if I check on a different TreeItem CheckBox, the selectedItem is Wrong.
If I select the top item and I want to perform some action on that items data, the change listener is called for ALL the children. This complicates matters. I only care of the state of the selected TreeItem which got checked/unchecked.
Is there no better way to add an action to the CheckBoxTreeItem than registering a ChangeListener?
3)
Uncheck the child will uncheck the parent, if there are no other siblings. I don't want that. However I want the children to be "gone"/unchecked if the parent is unchecked, but I don't want to be notified of it. If I uncheck and there are children, all the children should be unchecked. However I am not interesting in the change event of subitems of the unchecked item. My problem is still that all items below will fire a change event, and not just on the item I am interested in.
I could set each TreeItem independent. Then collapse the expanded item when it is unchecked. The children would still have its state independent from its parent checked or unchecked, but will not be visible.
Issue 1 are the most important problem I have. Checking the CheckBox needs to select the TreeItem of that CheckBox.
Issue 2 works with ChangeListener though I wish there was a better option, and the problem here can be circumvented by setting all items as independent.
Issue 3 I can also circumvent by setting all items to independent and hide them when parent is unchecked. They still maintain their state, but are out of sight.
A small test application
package com.company;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.scene.Scene;
import javafx.scene.control.CheckBoxTreeItem;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.layout.GridPane;
import javafx.scene.text.Text;
import javafx.stage.Stage;
public class MineAppTest extends Application {
private TreeView<Mine> treeView;
private MineChangeListener mineChangeListener = new MineChangeListener();
public static void main(String[] argv) {
MineAppTest.launch();
}
/* (non-Javadoc)
* #see javafx.application.Application#start(javafx.stage.Stage)
*/
#Override
public void start(Stage primaryStage) throws Exception {
GridPane contentPane = new GridPane();
contentPane.getChildren().add(new Text("Hello World!"));
treeView = new TreeView<>();
treeView.setCellFactory(new MineTreeCellFactory());
treeView.setOnMousePressed(event -> {
TreeItem<Mine> selectedItem = treeView.getSelectionModel().getSelectedItem();
boolean selected = ((CheckBoxTreeItem<Mine>)selectedItem).isSelected();
((CheckBoxTreeItem<Mine>)selectedItem).setSelected(!selected);
selectedItem.setExpanded(!selected);
});
treeView.setShowRoot(false);
Mine mine1 = new Mine("mine", true);
CheckBoxTreeItem<Mine> rootItem = new CheckBoxTreeItem<>(mine1, null, true);
rootItem.setExpanded(true);
treeView.setRoot(rootItem);
Mine mine2 = new Mine("test1", true);
CheckBoxTreeItem<Mine> item1Level1 = new CheckBoxTreeItem<>(mine2, null, mine2.isEnabled());
item1Level1.setExpanded(true);
//item1Level1.setIndependent(true);
item1Level1.selectedProperty().addListener(mineChangeListener);
rootItem.getChildren().add(item1Level1);
Mine mine3 = new Mine("subtest1", true);
CheckBoxTreeItem<Mine> item1Level2 = new CheckBoxTreeItem<>(mine3, null, mine3.isEnabled());
item1Level2.setExpanded(true);
//item1Level2.setIndependent(true);
item1Level2.selectedProperty().addListener(mineChangeListener);
item1Level1.getChildren().add(item1Level2);
Mine mine4 = new Mine("subtest2", true);
CheckBoxTreeItem<Mine> item2Level2 = new CheckBoxTreeItem<>(mine4, null, mine4.isEnabled());
item2Level2.setExpanded(true);
//item2Level2.setIndependent(true);
item2Level2.selectedProperty().addListener(mineChangeListener);
item1Level1.getChildren().add(item2Level2);
Mine mine5 = new Mine("test2", true);
CheckBoxTreeItem<Mine> item2Level1 = new CheckBoxTreeItem<>(mine5, null, mine5.isEnabled());
item2Level1.setExpanded(true);
//item2Level1.setIndependent(true);
item2Level1.selectedProperty().addListener(mineChangeListener);
item1Level1.getChildren().add(item2Level1);
Mine mine6 = new Mine("subtest2", true);
CheckBoxTreeItem<Mine> item4Level2 = new CheckBoxTreeItem<>(mine6, null, mine6.isEnabled());
item4Level2.setExpanded(true);
//item4Level2.setIndependent(true);
item4Level2.selectedProperty().addListener(mineChangeListener);
item2Level1.getChildren().add(item4Level2);
Mine mine7 = new Mine("subtest3", true);
CheckBoxTreeItem<Mine> item5Level2 = new CheckBoxTreeItem<>(mine7, null, mine6.isEnabled());
item5Level2.setExpanded(true);
//item5Level2.setIndependent(true);
item5Level2.selectedProperty().addListener(mineChangeListener);
item4Level2.getChildren().add(item5Level2);
contentPane.getChildren().add(treeView);
primaryStage.setScene(new Scene(contentPane));
primaryStage.setWidth(200);
primaryStage.setHeight(400);
primaryStage.setTitle("JavaFX 8 app");
primaryStage.setOnCloseRequest(event -> Platform.exit());
primaryStage.show();
}
private class MineChangeListener implements ChangeListener<Boolean> {
/* (non-Javadoc)
* #see javafx.beans.value.ChangeListener#changed(javafx.beans.value.ObservableValue, java.lang.Object, java.lang.Object)
*/
#Override
public void changed(ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean newValue) {
CheckBoxTreeItem<Mine> item = (CheckBoxTreeItem<Mine>) treeView.getSelectionModel().getSelectedItem();
if (newValue) {
// Do some work on the data in the selected TreeItem
}
}
}
}
package com.company;
import javafx.scene.control.TreeCell;
import javafx.scene.control.TreeView;
import javafx.scene.control.cell.CheckBoxTreeCell;
import javafx.util.Callback;
public class MineTreeCellFactory implements Callback<TreeView<Mine>, TreeCell<Mine>> {
/* (non-Javadoc)
* #see javafx.util.Callback#call(java.lang.Object)
*/
#Override
public TreeCell<Mine> call(TreeView<Mine> param) {
CheckBoxTreeCell<Mine> cell = new CheckBoxTreeCell<Mine>() {
/* (non-Javadoc)
* #see javafx.scene.control.Cell#updateItem(java.lang.Object, boolean)
*/
#Override
public void updateItem(Mine item, boolean empty) {
if (item == getItem() || (item != null && item.equals(getItem()))) {
return;
}
super.updateItem(item, empty);
if (empty) {
setText(null);
setGraphic(null);
} else {
if (item != null) {
setText(item.getName());
} else {
setText(null);
setGraphic(null);
}
}
}
};
return cell;
}
}
package com.company;
import javafx.beans.property.SimpleBooleanProperty;
public class Mine {
private final String name;
private final SimpleBooleanProperty enabled;
public Mine(String name, boolean enabled) {
this.name = name;
this.enabled = new SimpleBooleanProperty(enabled);
}
/**
* #return the name
*/
public String getName() {
return name;
}
/**
* #return the description
*/
public String getDescription() {
return description;
}
public SimpleBooleanProperty enabledProperty() {
return enabled;
}
/**
* #return the isDisabled
*/
public boolean isEnabled() {
return enabled.get();
}
}