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I am trying to place a few components inside a ScrollPane. These components should have the ability to be moved across this pane by mouse (click and drag). The ScrollPane itself is pannable and zoomable.
Now if I pick one of them and drag it to a new position the mouse is faster than the component if I have zoomed out. When zoomed in, the component gets moved faster than the mouse movement.
If not zoomed it works until I reach a certain position where the ScrollPane automatically pans.
It must have to do something with the determined coordinates of the nodes. Does anyone have an idea what I have to add to make it work correctly?
My controller class:
public class MainWindowController implements Initializable {
private final double SCALE_DELTA = 1.1;
private final StackPane zoomPane = new StackPane();
private Group group = new Group();
@FXML
private ScrollPane scrollPane;
@Override
public void initialize(URL url, ResourceBundle rb) {
Node node1 = new Node("Test");
Node node2 = new Node("Test2", 100, 200);
group.getChildren().addAll(node1, node2);
zoomPane.getChildren().add(group);
Group scrollContent = new Group(zoomPane);
scrollPane.setContent(scrollContent);
scrollPane.viewportBoundsProperty().addListener((ObservableValue<? extends Bounds> observable,
Bounds oldValue, Bounds newValue) -> {
zoomPane.setMinSize(newValue.getWidth(), newValue.getHeight());
});
zoomPane.setOnScroll(
(ScrollEvent event) -> {
event.consume();
if (event.getDeltaY() == 0) {
return;
}
double scaleFactor = (event.getDeltaY() > 0) ? SCALE_DELTA : 1 / SCALE_DELTA;
Point2D scrollOffset = figureScrollOffset(scrollContent, scrollPane);
group.setScaleX(group.getScaleX() * scaleFactor);
group.setScaleY(group.getScaleY() * scaleFactor);
repositionScroller(scrollContent, scrollPane, scaleFactor, scrollOffset);
}
);
group.getChildren()
.add(new Node("Test3", 500, 500));
}
private Point2D figureScrollOffset(javafx.scene.Node scrollContent, ScrollPane scroller) {
double extraWidth = scrollContent.getLayoutBounds().getWidth() - scroller.getViewportBounds().getWidth();
double hScrollProportion = (scroller.getHvalue() - scroller.getHmin()) / (scroller.getHmax() - scroller.getHmin());
double scrollXOffset = hScrollProportion * Math.max(0, extraWidth);
double extraHeight = scrollContent.getLayoutBounds().getHeight() - scroller.getViewportBounds().getHeight();
double vScrollProportion = (scroller.getVvalue() - scroller.getVmin()) / (scroller.getVmax() - scroller.getVmin());
double scrollYOffset = vScrollProportion * Math.max(0, extraHeight);
return new Point2D(scrollXOffset, scrollYOffset);
}
private void repositionScroller(javafx.scene.Node scrollContent, ScrollPane scroller, double scaleFactor, Point2D scrollOffset) {
double scrollXOffset = scrollOffset.getX();
double scrollYOffset = scrollOffset.getY();
double extraWidth = scrollContent.getLayoutBounds().getWidth() - scroller.getViewportBounds().getWidth();
if (extraWidth > 0) {
double halfWidth = scroller.getViewportBounds().getWidth() / 2;
double newScrollXOffset = (scaleFactor - 1) * halfWidth + scaleFactor * scrollXOffset;
scroller.setHvalue(scroller.getHmin() + newScrollXOffset * (scroller.getHmax() - scroller.getHmin()) / extraWidth);
} else {
scroller.setHvalue(scroller.getHmin());
}
double extraHeight = scrollContent.getLayoutBounds().getHeight() - scroller.getViewportBounds().getHeight();
if (extraHeight > 0) {
double halfHeight = scroller.getViewportBounds().getHeight() / 2;
double newScrollYOffset = (scaleFactor - 1) * halfHeight + scaleFactor * scrollYOffset;
scroller.setVvalue(scroller.getVmin() + newScrollYOffset * (scroller.getVmax() - scroller.getVmin()) / extraHeight);
} else {
scroller.setHvalue(scroller.getHmin());
}
}
}
The node class:
public class Node extends Parent {
private NodeStatus status = NodeStatus.OK;
private final Image okImage = new Image(getClass().getResourceAsStream("/images/MasterOK.png"));
private ImageView image = new ImageView(okImage);
private final Text label = new Text();
private final Font font = Font.font("Courier", 20);
double orgSceneX, orgSceneY;
double layoutX, layoutY;
public Node(String labelText) {
this(labelText, 0, 0);
}
public Node(String labelText, double x, double y) {
label.setText(labelText);
label.setFont(font);
label.setLayoutX(okImage.getWidth() + 10);
label.setLayoutY(okImage.getHeight() / 2 + 10);
getChildren().add(image);
getChildren().add(label);
setLayoutX(x);
setLayoutY(y);
setCursor(Cursor.MOVE);
setOnMousePressed(new EventHandler<MouseEvent>() {
@Override
public void handle(MouseEvent t) {
orgSceneX = t.getSceneX();
orgSceneY = t.getSceneY();
layoutX = getLayoutX();
layoutY = getLayoutY();
}
});
setOnMouseDragged(new EventHandler<MouseEvent>() {
@Override
public void handle(MouseEvent t) {
setLayoutX(layoutX + t.getSceneX() - orgSceneX);
setLayoutY(layoutY + t.getSceneY() - orgSceneY);
}
});
}
public NodeStatus getStatus() {
return status;
}
public void setStatus(NodeStatus status) {
this.status = status;
}
}
class Delta {
double x, y;
}
and the fxml:
<?xml version="1.0" encoding="UTF-8"?>
<?import java.lang.*?>
<?import java.util.*?>
<?import javafx.scene.*?>
<?import javafx.scene.control.*?>
<?import javafx.scene.layout.*?>
<?import nodes.*?>
<AnchorPane id="AnchorPane" prefHeight="600.0" prefWidth="800.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="cqsmonitor.MainWindowController">
<children>
<Pane layoutX="666.0" layoutY="14.0" prefHeight="572.0" prefWidth="114.0" AnchorPane.bottomAnchor="14.0" AnchorPane.rightAnchor="14.0" AnchorPane.topAnchor="14.0">
<children>
<TextField layoutY="30.0" prefHeight="25.0" prefWidth="114.0" />
<Label layoutY="12.0" text="Search:" />
<ChoiceBox layoutY="90.0" prefHeight="25.0" prefWidth="114.0" />
<Label layoutY="73.0" text="View:" />
</children>
</Pane>
<ScrollPane fx:id="scrollPane" layoutX="14.0" layoutY="14.0" pannable="true" prefHeight="571.0" prefWidth="644.0" AnchorPane.bottomAnchor="15.0" AnchorPane.leftAnchor="14.0" AnchorPane.rightAnchor="142.0" AnchorPane.topAnchor="14.0">
</ScrollPane>
</children>
</AnchorPane>
330
Since nobody answered yet, here's some code. I don't want to dig into yours and re-invent the wheel.
You can move nodes by dragging with the left mouse button, scale the pane with the mouse wheel, pan the pane with the right mouse button. No ScrollPane needed. However, if you want ScrollBars, you can always add them if you prefer them.
The code:
import javafx.application.Application;
import javafx.beans.property.DoubleProperty;
import javafx.beans.property.SimpleDoubleProperty;
import javafx.event.EventHandler;
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.input.MouseEvent;
import javafx.scene.input.ScrollEvent;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Circle;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;
/**
* The canvas which holds all of the nodes of the application.
*/
class PannableCanvas extends Pane {
DoubleProperty myScale = new SimpleDoubleProperty(1.0);
public PannableCanvas() {
setPrefSize(600, 600);
setStyle("-fx-background-color: lightgrey; -fx-border-color: blue;");
// add scale transform
scaleXProperty().bind(myScale);
scaleYProperty().bind(myScale);
// logging
addEventFilter(MouseEvent.MOUSE_PRESSED, event -> {
System.out.println(
"canvas event: " + ( ((event.getSceneX() - getBoundsInParent().getMinX()) / getScale()) + ", scale: " + getScale())
);
System.out.println( "canvas bounds: " + getBoundsInParent());
});
}
/**
* Add a grid to the canvas, send it to back
*/
public void addGrid() {
double w = getBoundsInLocal().getWidth();
double h = getBoundsInLocal().getHeight();
// add grid
Canvas grid = new Canvas(w, h);
// don't catch mouse events
grid.setMouseTransparent(true);
GraphicsContext gc = grid.getGraphicsContext2D();
gc.setStroke(Color.GRAY);
gc.setLineWidth(1);
// draw grid lines
double offset = 50;
for( double i=offset; i < w; i+=offset) {
// vertical
gc.strokeLine( i, 0, i, h);
// horizontal
gc.strokeLine( 0, i, w, i);
}
getChildren().add( grid);
grid.toBack();
}
public double getScale() {
return myScale.get();
}
/**
* Set x/y scale
* @param myScale
*/
public void setScale( double scale) {
myScale.set(scale);
}
/**
* Set x/y pivot points
* @param x
* @param y
*/
public void setPivot( double x, double y) {
setTranslateX(getTranslateX()-x);
setTranslateY(getTranslateY()-y);
}
}
/**
* Mouse drag context used for scene and nodes.
*/
class DragContext {
double mouseAnchorX;
double mouseAnchorY;
double translateAnchorX;
double translateAnchorY;
}
/**
* Listeners for making the nodes draggable via left mouse button. Considers if parent is zoomed.
*/
class NodeGestures {
private DragContext nodeDragContext = new DragContext();
PannableCanvas canvas;
public NodeGestures( PannableCanvas canvas) {
this.canvas = canvas;
}
public EventHandler<MouseEvent> getOnMousePressedEventHandler() {
return onMousePressedEventHandler;
}
public EventHandler<MouseEvent> getOnMouseDraggedEventHandler() {
return onMouseDraggedEventHandler;
}
private EventHandler<MouseEvent> onMousePressedEventHandler = new EventHandler<MouseEvent>() {
public void handle(MouseEvent event) {
// left mouse button => dragging
if( !event.isPrimaryButtonDown())
return;
nodeDragContext.mouseAnchorX = event.getSceneX();
nodeDragContext.mouseAnchorY = event.getSceneY();
Node node = (Node) event.getSource();
nodeDragContext.translateAnchorX = node.getTranslateX();
nodeDragContext.translateAnchorY = node.getTranslateY();
}
};
private EventHandler<MouseEvent> onMouseDraggedEventHandler = new EventHandler<MouseEvent>() {
public void handle(MouseEvent event) {
// left mouse button => dragging
if( !event.isPrimaryButtonDown())
return;
double scale = canvas.getScale();
Node node = (Node) event.getSource();
node.setTranslateX(nodeDragContext.translateAnchorX + (( event.getSceneX() - nodeDragContext.mouseAnchorX) / scale));
node.setTranslateY(nodeDragContext.translateAnchorY + (( event.getSceneY() - nodeDragContext.mouseAnchorY) / scale));
event.consume();
}
};
}
/**
* Listeners for making the scene's canvas draggable and zoomable
*/
class SceneGestures {
private static final double MAX_SCALE = 10.0d;
private static final double MIN_SCALE = .1d;
private DragContext sceneDragContext = new DragContext();
PannableCanvas canvas;
public SceneGestures( PannableCanvas canvas) {
this.canvas = canvas;
}
public EventHandler<MouseEvent> getOnMousePressedEventHandler() {
return onMousePressedEventHandler;
}
public EventHandler<MouseEvent> getOnMouseDraggedEventHandler() {
return onMouseDraggedEventHandler;
}
public EventHandler<ScrollEvent> getOnScrollEventHandler() {
return onScrollEventHandler;
}
private EventHandler<MouseEvent> onMousePressedEventHandler = new EventHandler<MouseEvent>() {
public void handle(MouseEvent event) {
// right mouse button => panning
if( !event.isSecondaryButtonDown())
return;
sceneDragContext.mouseAnchorX = event.getSceneX();
sceneDragContext.mouseAnchorY = event.getSceneY();
sceneDragContext.translateAnchorX = canvas.getTranslateX();
sceneDragContext.translateAnchorY = canvas.getTranslateY();
}
};
private EventHandler<MouseEvent> onMouseDraggedEventHandler = new EventHandler<MouseEvent>() {
public void handle(MouseEvent event) {
// right mouse button => panning
if( !event.isSecondaryButtonDown())
return;
canvas.setTranslateX(sceneDragContext.translateAnchorX + event.getSceneX() - sceneDragContext.mouseAnchorX);
canvas.setTranslateY(sceneDragContext.translateAnchorY + event.getSceneY() - sceneDragContext.mouseAnchorY);
event.consume();
}
};
/**
* Mouse wheel handler: zoom to pivot point
*/
private EventHandler<ScrollEvent> onScrollEventHandler = new EventHandler<ScrollEvent>() {
@Override
public void handle(ScrollEvent event) {
double delta = 1.2;
double scale = canvas.getScale(); // currently we only use Y, same value is used for X
double oldScale = scale;
if (event.getDeltaY() < 0)
scale /= delta;
else
scale *= delta;
scale = clamp( scale, MIN_SCALE, MAX_SCALE);
double f = (scale / oldScale)-1;
double dx = (event.getSceneX() - (canvas.getBoundsInParent().getWidth()/2 + canvas.getBoundsInParent().getMinX()));
double dy = (event.getSceneY() - (canvas.getBoundsInParent().getHeight()/2 + canvas.getBoundsInParent().getMinY()));
canvas.setScale( scale);
// note: pivot value must be untransformed, i. e. without scaling
canvas.setPivot(f*dx, f*dy);
event.consume();
}
};
public static double clamp( double value, double min, double max) {
if( Double.compare(value, min) < 0)
return min;
if( Double.compare(value, max) > 0)
return max;
return value;
}
}
/**
* An application with a zoomable and pannable canvas.
*/
public class ZoomAndScrollApplication extends Application {
public static void main(String[] args) {
launch(args);
}
@Override
public void start(Stage stage) {
Group group = new Group();
// create canvas
PannableCanvas canvas = new PannableCanvas();
// we don't want the canvas on the top/left in this example => just
// translate it a bit
canvas.setTranslateX(100);
canvas.setTranslateY(100);
// create sample nodes which can be dragged
NodeGestures nodeGestures = new NodeGestures( canvas);
Label label1 = new Label("Draggable node 1");
label1.setTranslateX(10);
label1.setTranslateY(10);
label1.addEventFilter( MouseEvent.MOUSE_PRESSED, nodeGestures.getOnMousePressedEventHandler());
label1.addEventFilter( MouseEvent.MOUSE_DRAGGED, nodeGestures.getOnMouseDraggedEventHandler());
Label label2 = new Label("Draggable node 2");
label2.setTranslateX(100);
label2.setTranslateY(100);
label2.addEventFilter( MouseEvent.MOUSE_PRESSED, nodeGestures.getOnMousePressedEventHandler());
label2.addEventFilter( MouseEvent.MOUSE_DRAGGED, nodeGestures.getOnMouseDraggedEventHandler());
Label label3 = new Label("Draggable node 3");
label3.setTranslateX(200);
label3.setTranslateY(200);
label3.addEventFilter( MouseEvent.MOUSE_PRESSED, nodeGestures.getOnMousePressedEventHandler());
label3.addEventFilter( MouseEvent.MOUSE_DRAGGED, nodeGestures.getOnMouseDraggedEventHandler());
Circle circle1 = new Circle( 300, 300, 50);
circle1.setStroke(Color.ORANGE);
circle1.setFill(Color.ORANGE.deriveColor(1, 1, 1, 0.5));
circle1.addEventFilter( MouseEvent.MOUSE_PRESSED, nodeGestures.getOnMousePressedEventHandler());
circle1.addEventFilter( MouseEvent.MOUSE_DRAGGED, nodeGestures.getOnMouseDraggedEventHandler());
Rectangle rect1 = new Rectangle(100,100);
rect1.setTranslateX(450);
rect1.setTranslateY(450);
rect1.setStroke(Color.BLUE);
rect1.setFill(Color.BLUE.deriveColor(1, 1, 1, 0.5));
rect1.addEventFilter( MouseEvent.MOUSE_PRESSED, nodeGestures.getOnMousePressedEventHandler());
rect1.addEventFilter( MouseEvent.MOUSE_DRAGGED, nodeGestures.getOnMouseDraggedEventHandler());
canvas.getChildren().addAll(label1, label2, label3, circle1, rect1);
group.getChildren().add(canvas);
// create scene which can be dragged and zoomed
Scene scene = new Scene(group, 1024, 768);
SceneGestures sceneGestures = new SceneGestures(canvas);
scene.addEventFilter( MouseEvent.MOUSE_PRESSED, sceneGestures.getOnMousePressedEventHandler());
scene.addEventFilter( MouseEvent.MOUSE_DRAGGED, sceneGestures.getOnMouseDraggedEventHandler());
scene.addEventFilter( ScrollEvent.ANY, sceneGestures.getOnScrollEventHandler());
stage.setScene(scene);
stage.show();
canvas.addGrid();
}
}
Let me know if this doesn't help you at all, then I'll delete the post. I'm not interested in the bounty.
96
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