Question

鉴于带有一些子节点的巨大AnchorPane是ScrollPane的内容，我如何滚动以使其中一个子节点在当前视口之外可见？

Answer 1

您需要在content内找到此内部节点的坐标，并相应地调整ScrollPane的{{1}}和vValue。

请参阅下一个小应用中的hValue方法：

ensureVisible()

Answer 2

我为这个案例创建了一个稍微优雅的版本。但是，我只能在y轴上进行测试。希望它有所帮助

private static void ensureVisible(ScrollPane pane, Node node) {
    Bounds viewport = scrollPane.getViewportBounds();
    double contentHeight = scrollPane.getContent().localToScene(scrollPane.getContent().getBoundsInLocal()).getHeight();
    double nodeMinY = node.localToScene(node.getBoundsInLocal()).getMinY();
    double nodeMaxY = node.localToScene(node.getBoundsInLocal()).getMaxY();

    double vValueDelta = 0;
    double vValueCurrent = scrollPane.getVvalue();

    if (nodeMaxY < 0) {
        // currently located above (remember, top left is (0,0))
        vValueDelta = (nodeMinY - viewport.getHeight()) / contentHeight;
    } else if (nodeMinY > viewport.getHeight()) {
        // currently located below
        vValueDelta = (nodeMinY + viewport.getHeight()) / contentHeight;
    }
    scrollPane.setVvalue(vValueCurrent + vValueDelta);
}

Answer 3

要获得完美的快照，您需要考虑滚动条的开始和停止位置。视口从0（Bounds scollpane）的一半视口开始，从max Bound停止一半的视口。 bounds vs viewport picture

如此：半视口下的节点Y-> setVvalue设置为0 maxheigh-half视口上方的节点Y->将值设置为1

，在这之间，我们需要计算总高度-1viewport（一半起点在end的一半）和节点y-half viewport。然后（节点y-半视口）/（总高度-1视口）

                double heightViewPort = scrollPane.getViewportBounds().getHeight();
                double heightScrollPane = scrollPane.getContent().getBoundsInLocal().getHeight();
                double y = Label.getBoundsInParent().getMaxY();
                if (y<(heightViewPort/2)){
                    scrollPane.setVvalue(0);
                    // below 0 of scrollpane

                }else if ((y>=(heightViewPort/2))&(y<=(heightScrollPane-heightViewPort/2))){
                   // between 0 and 1 of scrollpane
                    scrollPane.setVvalue((y-(heightViewPort/2))/(heightScrollPane-heightViewPort));
                }
                else if(y>= (heightScrollPane-(heightViewPort/2))){
                    // above 1 of scrollpane
                    scrollPane.setVvalue(1);

                }

如何滚动以在ScrollPane的内容中显示节点？

3 个答案: