The trigger for this was a quick experiment to solve TreeItem selection width: the requirement is to highlight only the text, not the whole tree cell. Nothing easier than that (said Frederik :)
- implement a custom TreeCell with a Label as graphic (and configure the label with the item as needed)
- remove the selection style (mostly the highlight background from the cell
- add the highlight style to the label
Something like (a runnable example using this is at the end):
public static class MyTreeCell extends TreeCell<String> {
private Label label;
public MyTreeCell() {
getStyleClass().add("tree-text-only");
}
@Override
public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setText(null);
setGraphic(null);
} else {
if (label == null) {
label = new Label();
}
label.setText(item);
setGraphic(label);
}
}
}
The css:
/* remove the highlight from cell as a whole,
c&p'd the unselected style from modena */
.tree-text-only:filled:selected {
-fx-background: -fx-control-inner-background;
-fx-background-color: -fx-background;
}
/* c&p'd selected style */
/* using > doesn't make a different to the behaviour */
/* .tree-text-only:filled:selected > .label { */
.tree-text-only:filled:selected .label {
/* following is the selection color from themes, doesn't show */
-fx-background: -fx-selection-bar;
/* hard-coded color does show */
/* -fx-background-color: -fx-accent ; */
/* auto-adjust text fill */
/* no effect for hard-coded color, showing nothing for selection bar */
-fx-text-fill: -fx-text-background-color;
}
Expected behaviour
- label has highlighted background when using selection-bar
- text auto-adjusts its fill
Actual behaviour:
- using the "semantic" (?) highlight color selection-bar, the background color of the label is not changed to the highlight color but the text fill is changed to the "white", so the text doesn't show
- using a hard-coded color (any, even the accent as above) changes the label's background but the text fill isn't updated
The obvious question: How to make it work as expected?
For convenience, a runnable example:
public class TreeCellExample extends Application {
public static class MyTreeCell extends TreeCell<String> {
private Label label;
public MyTreeCell() {
getStyleClass().add("tree-text-only");
}
@Override
public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setText(null);
setGraphic(null);
} else {
if (label == null) {
label = new Label();
}
label.setText(item);
setGraphic(label);
}
}
}
private Parent getContent() {
TreeItem root = createSubTree("root");
root.setExpanded(true);
TreeView tree = new TreeView(root);
tree.getStylesheets().add(
getClass().getResource("treetextonly.css").toExternalForm());
tree.setCellFactory(p -> new MyTreeCell());
BorderPane pane = new BorderPane(tree);
return pane;
}
ObservableList rawItems = FXCollections.observableArrayList(
"9-item", "8-item", "7-item", "6-item",
"5-item", "4-item", "3-item", "2-item", "1-item");
protected TreeItem createSubTree(Object value) {
TreeItem child = new TreeItem(value);
child.getChildren().setAll((List<TreeItem>) rawItems.stream()
.map(TreeItem::new)
.collect(Collectors.toList()));
return child;
}
@Override
public void start(Stage primaryStage) throws Exception {
Scene scene = new Scene(getContent());
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
