问题：
JavaFX8-在滚动窗格中拖动窗格
方宜
基于此注释https://stackoverflow.com/a/29530135/1387524，我添加了一个ScrollPane，以便在画布移到可见区域之外时使用滚动。
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.control.ScrollPane;
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;
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);
}
/**
* 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) {
gc.strokeLine( i, 0, i, h);
gc.strokeLine( 0, i, w, i);
}
getChildren().add( grid);
grid.toBack();
}
public double getScale() {
return myScale.get();
}
public void setScale( double scale) {
myScale.set(scale);
}
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);
Pane pane = new Pane(group);
ScrollPane scrollPane = new ScrollPane(pane);
// create scene which can be dragged and zoomed
Scene scene = new Scene(scrollPane, 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();
}
}
共有1个答案
夹谷承安
创建一个类ZoomableScrollPane，并将该窗格传递给ZoomandScrollApplication中的ZoomableScrollPane（窗格）。
图像：边有滚动条边有缩放功能
Pane pane = new Pane(group);
ZoomableScrollPane zs = new ZoomableScrollPane(pane);
// create scene which can be dragged and zoomed
Scene scene = new Scene(zs, 1024, 768);
/
import javafx.geometry.Bounds;
import javafx.geometry.Point2D;
import javafx.geometry.Pos;
import javafx.scene.Group;
import javafx.scene.Node;
import javafx.scene.control.ScrollPane;
import javafx.scene.layout.VBox;
public class ZoomableScrollPane extends ScrollPane {
private double scaleValue = 0.7;
private double zoomIntensity = 0.04;
private Node target;
private Node zoomNode;
public ZoomableScrollPane(Node target) {
super();
this.target = target;
this.zoomNode = new Group(target);
setContent(outerNode(zoomNode));
setPannable(true);
setHbarPolicy(ScrollPane.ScrollBarPolicy.AS_NEEDED);
setVbarPolicy(ScrollPane.ScrollBarPolicy.AS_NEEDED);
setFitToHeight(true); //center
setFitToWidth(true); //center
updateScale();
}
private Node outerNode(Node node) {
Node outerNode = centeredNode(node);
outerNode.setOnScroll(e -> {
e.consume();
onScroll(e.getTextDeltaY(), new Point2D(e.getX(), e.getY()));
});
return outerNode;
}
private Node centeredNode(Node node) {
VBox vBox = new VBox(node);
vBox.setAlignment(Pos.CENTER);
return vBox;
}
private void updateScale() {
target.setScaleX(scaleValue);
target.setScaleY(scaleValue);
}
private void onScroll(double wheelDelta, Point2D mousePoint) {
double zoomFactor = Math.exp(wheelDelta * zoomIntensity);
Bounds innerBounds = zoomNode.getLayoutBounds();
Bounds viewportBounds = getViewportBounds();
// calculate pixel offsets from [0, 1] range
double valX = this.getHvalue() * (innerBounds.getWidth() - viewportBounds.getWidth());
double valY = this.getVvalue() * (innerBounds.getHeight() - viewportBounds.getHeight());
scaleValue = scaleValue * zoomFactor;
updateScale();
this.layout(); // refresh ScrollPane scroll positions & target bounds
// convert target coordinates to zoomTarget coordinates
Point2D posInZoomTarget = target.parentToLocal(zoomNode.parentToLocal(mousePoint));
// calculate adjustment of scroll position (pixels)
Point2D adjustment = target.getLocalToParentTransform().deltaTransform(posInZoomTarget.multiply(zoomFactor - 1));
// convert back to [0, 1] range
// (too large/small values are automatically corrected by ScrollPane)
Bounds updatedInnerBounds = zoomNode.getBoundsInLocal();
this.setHvalue((valX + adjustment.getX()) / (updatedInnerBounds.getWidth() - viewportBounds.getWidth()));
this.setVvalue((valY + adjustment.getY()) / (updatedInnerBounds.getHeight() - viewportBounds.getHeight()));
}
}
类似资料：
-
我将cell factory用于listview，并带有如下复选框： 它很好，但不是所有情况下。案例：当我说超过10个条目时，滚动窗格就出现了。假设我有位于8或9索引的beanChoices要检查（您必须滚动才能查看它们）。 对于不可见的项（位于scrollpane下）不调用监听器。 在调试时，我发现向下滚动时调用监听器。 问题：当我在上面的情况下从beanChoices中得到选中的值时，它返回空
-
问题我如何可以嵌入这个应用程序到SPlitPane，在左边将是另一个面板。 不幸的是，代码导致了错误的坐标，
-
我希望能够向下滚动动态生成的电影列表。我尝试添加滚动窗格。 我在页面的开头有一个导航栏，中间有一个包含所有电影的jpanel。 您可以使用以下代码重新创建此示例： 我想做的是用我的鼠标滚轮向下滚动这个电影列表，而不看任何滚动条。它现在看起来应该和现在一模一样，但我希望能够向下滚动，看到所有的电影。 我不知道为什么它不起作用，这就是为什么我在这里问，希望有人能向我解释我做错了什么。
-
问题内容： 当内容的高度增加时，有什么方法可以自动向下滚动ScrollPane控件？例如，我在屏幕底部（在ScrollPane内部）有一个TitledPane，当我展开它时，我希望ScrollPane向下滚动，以便可以看到TitledPane的全部内容。 问题答案： 您可以结合使用和和来实现该行为 第一个是获取titlePane的坐标，第二个是设置scrollPane的垂直栏位置。请注意，它的范围
-
我试图将乘法VBox添加到scrollpane中的gridpane（在下面的codesnippet中称为refPane）。 它在一行中添加不超过ITEMS_PER_ROW的Vbox，并在下一行中继续。也不应该有更多的行，然后ITEMS_PER_COLUM可见。问题是，如果我添加更多的ITEMS_PER_ROW*ITEMS_PER_COLUMN到网格中，而不是obingbeingscrollable
-
有人能举一个简单的例子来说明如何设置EventHandler以在窗格（JavaFX）上拖动图像视图。对于拖动，我的意思是在图像上按下鼠标，拖动和图像应该跟随，然后释放鼠标，图像视图将停止在该位置。