你好,因为scrollpane
的内置平移工具问题(运行缓慢,块状过渡而不是流畅)我试图创建一个自定义平移处理程序。以下是我的尝试,但if语句无法正常工作。
mapScroll.addEventFilter(MouseEvent.MOUSE_PRESSED, e -> {
startX = e.getX();
startY = e.getY();
});
mapScroll.addEventFilter(MouseEvent.MOUSE_DRAGGED, e -> {
endX = e.getX();
endY = e.getY();
Bounds viewBounds = mapScroll.getViewportBounds();
Bounds mapBounds = mapScroll.getBoundsInParent();
double xMin = viewBounds.getMinX();
double xMax = viewBounds.getMaxX();
double yMin = viewBounds.getMinY();
double yMax = viewBounds.getMaxY();
double startEndX = endX - startX;
double startEndY = endY - startY;
if(mapBounds.contains(xMin + startEndX, yMin + startEndY) && mapBounds.contains(xMin + startEndX, yMax + startEndY) && mapBounds.contains(xMax + startEndX, yMin + startEndY) && mapBounds.contains(xMax + startEndX, yMax + startEndY))
{
double fullWidth = mapScroll.getWidth();
double fullHeight = mapScroll.getHeight();
double hChange = startEndX/fullWidth;
double vChange = startEndY/fullHeight;
mapScroll.setHvalue(mapScroll.getHvalue() + hChange);
mapScroll.setVvalue(mapScroll.getVvalue() + vChange);
}
endX = startX;
endY = startY;
});
答案 0 :(得分:1)
您永远不会在计算中使用内容的宽度。这意味着无论内容的大小如何,您都必须将鼠标移动相同的距离才能从一侧滚动到另一侧。内容是否比视口大10个像素,或者内容是视口大小的10倍,这对您的代码没有任何影响。此外请注意
endX = startX;
endY = startY;
绝对无用,因为无论如何都会在事件过滤器的每次调用开始时覆盖值。你可能想要反过来做任务。
此外,您可以将滚动位置移动到与鼠标移动相同的方向。但是,如果您希望鼠标位置相对于内容保持相同,则应该向相反方向移动滚动位置。
这是一个例子(为简单起见,删除了边界测试):
private double startX;
private double startY;
@Override
public void start(Stage primaryStage) {
ImageView image = new ImageView("https://upload.wikimedia.org/wikipedia/commons/thumb/e/ec/Mona_Lisa%2C_by_Leonardo_da_Vinci%2C_from_C2RMF_retouched.jpg/687px-Mona_Lisa%2C_by_Leonardo_da_Vinci%2C_from_C2RMF_retouched.jpg");
ScrollPane mapScroll = new ScrollPane(image);
Scene scene = new Scene(mapScroll, 400, 400);
mapScroll.addEventFilter(MouseEvent.MOUSE_PRESSED, e -> {
startX = e.getX();
startY = e.getY();
});
mapScroll.addEventFilter(MouseEvent.MOUSE_DRAGGED, e -> {
double endX = e.getX();
double endY = e.getY();
Bounds viewBounds = mapScroll.getViewportBounds();
double startEndX = startX - endX;
double startEndY = startY - endY;
Bounds contentBounds = mapScroll.getContent().getLayoutBounds();
double hChange = startEndX / (contentBounds.getWidth() - viewBounds.getWidth());
double vChange = startEndY / (contentBounds.getHeight() - viewBounds.getHeight());
mapScroll.setHvalue(mapScroll.getHvalue() + hChange);
mapScroll.setVvalue(mapScroll.getVvalue() + vChange);
startX = endX;
startY = endY;
});
primaryStage.setScene(scene);
primaryStage.show();
}