No vertical scrollbar since 0.7-M1

[Crystark]

Hi,

I just switch from a 2-weeks old 1.0.0-SNAPSHOT to 0.7-M1 and I seem to have lost the vertical scroll-bar in the editor. I can't even scroll with the mouse. I have to select the text and drag the mouse down so that the text field scrolls.

Tried reverting to 1.0.0-SNAPSHOT but that branch is now giving me the following error:

Caused by: java.lang.NoSuchMethodError: org.fxmisc.flowless.VirtualFlow.breadthOffsetProperty()Ljavafx/beans/property/ReadOnlyDoubleProperty;
    at org.fxmisc.richtext.StyledTextArea.createCell(StyledTextArea.java:1064)
    at org.fxmisc.richtext.StyledTextArea.lambda$new$3(StyledTextArea.java:549)
    at org.fxmisc.flowless.CellPool.getCell(CellPool.java:20)
    at org.fxmisc.flowless.CellListManager.cellForItem(CellListManager.java:75)
    at org.reactfx.collection.MappedList.get(MappedList.java:27)
    at org.reactfx.collection.MemoizationListImpl.get(MemoizationList.java:99)
    at org.fxmisc.flowless.CellListManager.getCell(CellListManager.java:64)
    at org.fxmisc.flowless.CellPositioner.getSizedCell(CellPositioner.java:129)
    at org.fxmisc.flowless.VirtualFlow.getCell(VirtualFlow.java:119)
    at org.fxmisc.richtext.StyledTextArea.followCaret(StyledTextArea.java:894)
    at org.fxmisc.richtext.StyledTextArea.layoutChildren(StyledTextArea.java:1035)
    at javafx.scene.Parent.layout(Parent.java:1079)
    at javafx.scene.Parent.layout(Parent.java:1085)
    at javafx.scene.Scene.doLayoutPass(Scene.java:552)
    at javafx.scene.Scene.preferredSize(Scene.java:1646)
    at javafx.scene.Scene.impl_preferredSize(Scene.java:1720)
    at javafx.stage.Window$9.invalidated(Window.java:846)
    at javafx.beans.property.BooleanPropertyBase.markInvalid(BooleanPropertyBase.java:109)
    at javafx.beans.property.BooleanPropertyBase.set(BooleanPropertyBase.java:144)
    at javafx.stage.Window.setShowing(Window.java:922)
    at javafx.stage.Window.show(Window.java:937)
    at javafx.stage.Stage.show(Stage.java:259)

I reverted to 0.6.10 in the meantime.

new VirtualizedScrollPane<>(new StyledTextArea());

[JordanMartinez]

@Crystark In the release notes:

The scroll-pane has been decoupled from the main content. To get scroll-bars, one now needs to wrap StyledTextArea in a VirtualizedScrollPane.

See @kuc's example

new VirtualizedScrollPane<>(new StyledTextArea());

[Crystark]

Just tried it and when I do so, i see a scroll bar but mouse scrolling doesn't work and clicking on the bar and dragging it up and down has an erratic behavior (sometimes scroll, sometimes doesn't).

stage = new Stage();
stage.setScene(new Scene(new StackPane(new VirtualizedScrollPane<>(new MyCodeArea()))));
stage.setMinWidth(600);
stage.setMinHeight(300);
stage.setWidth(760);
stage.setHeight(500);

I've extended CodeArea with to a class which adds syntax highlighting, a few keyboard shortcuts and bounds it to a file (to read/write). I don't think this can affect the scrollbar as it works fine with 0.6.10 but i thought i'd mention it.

[TomasMikula]

I guess I broke the scrollbar dimensions in the latest snapshot (easy to fix), but otherwise they work. I also cannot reproduce the mouse scroll problem.

[TomasMikula]

@Crystark I fixed the issue with scrollbars that I was referring to. Can you please provide a self-contained reproducible test case for the other issue?

[Crystark]

@TomasMikula i'll try to see what i can do. It's kinda hard forme to extract it right now.

I've managed to isolate what was making it fail: it's the syntax highlighting:

        EventStream<?> richChanges = richChanges();
        richChanges
            .successionEnds(Duration.ofMillis(1))
            .supplyTask(this::computeHighlightingAsync)
            .awaitLatest(richChanges)
            .filterMap(t -> {
                if (t.isSuccess()) {
                    return Optional.of(t.get());
                }
                else {
                    t.getFailure().printStackTrace();
                    return Optional.empty();
                }
            })
            .subscribe(this::applyHighlighting);

I'll continue digging.

[Crystark]

Fixed!

I changed it to:

        richChanges()
            .filter(ch -> !ch.getInserted().equals(ch.getRemoved()))
            .successionEnds(Duration.ofMillis(1))
            .supplyTask(this::computeHighlightingAsync)
            .awaitLatest(richChanges())
            .filterMap(t -> {
                if (t.isSuccess()) {
                    return Optional.of(t.get());
                }
                else {
                    t.getFailure().printStackTrace();
                    return Optional.empty();
                }
            })
            .subscribe(this::applyHighlighting);

As provided in the new example.

[Crystark]

Ok it's all good.

new VirtualizedScrollPane<>(new StyledTextArea()); works like a charm!
Thanks