JAVAFX缩放,在ScrollPane中滚动
作者：互联网
我有JAVAFX应用程序的缩放和缩放,如下所述：
Scale at pivot point in an already scaled node
我需要实现的是将图像放在右侧窗格中,并将图像保留在左侧,如下图所示.
题
如何将此应用程序嵌入到SPlitPane中,左侧将是另一个面板.
SplitPane splitPane = new SplitPane();
splitPane.getItems().add(new Label("Left Panel"));
splitPane.getItems().add(group);
Scene scene = new Scene(splitPane, 1024, 768);
不幸的是,代码导致坐标错误,
解决方法:
要在ScrollPane内部进行缩放,您需要调整滚动位置.如果没有使用ScrollPane,这比仅添加转换要复杂得多.
基本上,您需要在缩放节点之前检查当前滚动位置,并且在缩放之后修改滚动位置以防止枢轴点因缩放比例因子而改变其位置.
下面的示例允许您在网格中“围绕”移动圆圈,并在不单击圆圈(可平移的ScrollPane)时在网格中移动,此外还允许您在按住CTRL键的同时移动鼠标滚轮时调整缩放.
import java.net.MalformedURLException;
import javafx.application.Application;
import javafx.geometry.Bounds;
import javafx.geometry.Point2D;
import javafx.geometry.Pos;
import javafx.scene.Group;
import javafx.scene.Node;
import javafx.scene.Scene;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.control.Label;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.SplitPane;
import javafx.scene.layout.Pane;
import javafx.scene.layout.Region;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
import javafx.stage.Stage;
public class PivotZoom extends Application {
public static Region createContent() {
double width = 1000;
double height = 1000;
Canvas canvas = new Canvas(width, height);
GraphicsContext gc = canvas.getGraphicsContext2D();
gc.setFill(Color.LIGHTGREY);
gc.fillRect(0, 0, width, height);
gc.setStroke(Color.BLUE);
gc.beginPath();
for (int i = 50; i < width; i += 50) {
gc.moveTo(i, 0);
gc.lineTo(i, height);
}
for (int i = 50; i < height; i += 50) {
gc.moveTo(0, i);
gc.lineTo(width, i);
}
gc.stroke();
Pane content = new Pane(
new Circle(50, 50, 20),
new Circle(120, 90, 20, Color.RED),
new Circle(200, 70, 20, Color.GREEN)
);
StackPane result = new StackPane(canvas, content);
result.setAlignment(Pos.TOP_LEFT);
class DragData {
double startX;
double startY;
double startLayoutX;
double startLayoutY;
Node dragTarget;
}
DragData dragData = new DragData();
content.setOnMousePressed(evt -> {
if (evt.getTarget() != content) {
// initiate drag gesture, if a child of content receives the
// event to prevent ScrollPane from panning.
evt.consume();
evt.setDragDetect(true);
}
});
content.setOnDragDetected(evt -> {
Node n = (Node) evt.getTarget();
if (n != content) {
// set start paremeters
while (n.getParent() != content) {
n = n.getParent();
}
dragData.startX = evt.getX();
dragData.startY = evt.getY();
dragData.startLayoutX = n.getLayoutX();
dragData.startLayoutY = n.getLayoutY();
dragData.dragTarget = n;
n.startFullDrag();
evt.consume();
}
});
// stop dragging when mouse is released
content.setOnMouseReleased(evt -> dragData.dragTarget = null);
content.setOnMouseDragged(evt -> {
if (dragData.dragTarget != null) {
// move dragged node
dragData.dragTarget.setLayoutX(evt.getX() + dragData.startLayoutX - dragData.startX);
dragData.dragTarget.setLayoutY(evt.getY() + dragData.startLayoutY - dragData.startY);
Point2D p = new Point2D(evt.getX(), evt.getY());
evt.consume();
}
});
return result;
}
@Override
public void start(Stage primaryStage) throws MalformedURLException {
Region zoomTarget = createContent();
zoomTarget.setPrefSize(1000, 1000);
zoomTarget.setOnDragDetected(evt -> {
Node target = (Node) evt.getTarget();
while (target != zoomTarget && target != null) {
target = target.getParent();
}
if (target != null) {
target.startFullDrag();
}
});
Group group = new Group(zoomTarget);
// stackpane for centering the content, in case the ScrollPane viewport
// is larget than zoomTarget
StackPane content = new StackPane(group);
group.layoutBoundsProperty().addListener((observable, oldBounds, newBounds) -> {
// keep it at least as large as the content
content.setMinWidth(newBounds.getWidth());
content.setMinHeight(newBounds.getHeight());
});
ScrollPane scrollPane = new ScrollPane(content);
scrollPane.setPannable(true);
scrollPane.viewportBoundsProperty().addListener((observable, oldBounds, newBounds) -> {
// use vieport size, if not too small for zoomTarget
content.setPrefSize(newBounds.getWidth(), newBounds.getHeight());
});
content.setOnScroll(evt -> {
if (evt.isControlDown()) {
evt.consume();
final double zoomFactor = evt.getDeltaY() > 0 ? 1.2 : 1 / 1.2;
Bounds groupBounds = group.getLayoutBounds();
final Bounds viewportBounds = scrollPane.getViewportBounds();
// calculate pixel offsets from [0, 1] range
double valX = scrollPane.getHvalue() * (groupBounds.getWidth() - viewportBounds.getWidth());
double valY = scrollPane.getVvalue() * (groupBounds.getHeight() - viewportBounds.getHeight());
// convert content coordinates to zoomTarget coordinates
Point2D posInZoomTarget = zoomTarget.parentToLocal(group.parentToLocal(new Point2D(evt.getX(), evt.getY())));
// calculate adjustment of scroll position (pixels)
Point2D adjustment = zoomTarget.getLocalToParentTransform().deltaTransform(posInZoomTarget.multiply(zoomFactor - 1));
// do the resizing
zoomTarget.setScaleX(zoomFactor * zoomTarget.getScaleX());
zoomTarget.setScaleY(zoomFactor * zoomTarget.getScaleY());
// refresh ScrollPane scroll positions & content bounds
scrollPane.layout();
// convert back to [0, 1] range
// (too large/small values are automatically corrected by ScrollPane)
groupBounds = group.getLayoutBounds();
scrollPane.setHvalue((valX + adjustment.getX()) / (groupBounds.getWidth() - viewportBounds.getWidth()));
scrollPane.setVvalue((valY + adjustment.getY()) / (groupBounds.getHeight() - viewportBounds.getHeight()));
}
});
StackPane left = new StackPane(new Label("Left Menu"));
SplitPane root = new SplitPane(left, scrollPane);
Scene scene = new Scene(root, 800, 600);
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
标签：java,javafx,zooming,scrollpane 来源： https://codeday.me/bug/20190608/1199564.html