JavaFX TextArea Hiding Scroll Bars

问题:

I have a TextArea() and would like to hide the vertical/horizontal scroll bars. I see that the control seems to have a built in scroll-pane that shows as needed.

    TextArea numberPane = new TextArea();

    numberPane.setEditable(false);
    numberPane.setMaxWidth( 75 );

    // Set the characteristics of our line number pane
    numberPane.setId( "line-number-pane" );

In my CSS file I have the follow settings.

    #line-number-pane
    {
        -fx-text-fill: white;
        -fx-background-color: black;
        -fx-font: 12px "Courier New";
        -fx-font-family: "Courier New";
        -fx-font-weight: bold;
    }

    #line-number-pane .scroll-pane
    {
        -fx-hbar-policy : never;
        -fx-vbar-policy : never;
    }

As expected the text area font/color/size works just fine. However, the scroll-pane policy doesn't seem to work.

Should I be able to hide the scroll bars via the CSS file or is there some code that will do the trick.

Thanks.

回答1:

From How can I hide the scroll bar in TextArea?:

Remove Horizontal Scrollbar

textArea.setWrapText(true);

Remove Vertical Scrollbar

ScrollBar scrollBarv = (ScrollBar)ta.lookup(".scroll-bar:vertical");
scrollBarv.setDisable(true);

CSS

.text-area .scroll-bar:vertical:disabled {
    -fx-opacity: 0;
}

回答2:

I observed code of TextAreaSkin class, and found, that a void layoutChildren(x, y, w, h) method, which is called "during the layout pass of the scenegraph" and de facto, each time, when something happens with a control, contains a code, which changes hbarPolicy and vbarPolicy between AS_NEEDED and NEVER, according to the current state of control.

So, looks like, there is no chance to do somethign with it, using a css.

Try to just make scrollbars invisible. But, as I see code of ScrollPaneSkin, scrollBars are created once, but their visibility state seems to change during the control is working, so, instead of using setVisible(false) (which will be ignored in the nearest layout), try to use a setOpacity(0.0). (I'm not sure, it will work, but it worth to try).

Also, instead of CSS using, you can apply a recursive search of scrollBars in a control structure, using a Parent.getChildrenUnmodifiable() method, and make them invisible manually.