Javafx 2圖表縮放

Question

當我選擇圖表區域時，我的縮放會得到一個「小開關」。在例子中，如果從tick 3選擇到tick 6，我可以得到下限：3.67和上限6.74。

如何解決？

任何幫助真的很感激。

package testjavafxzoom; 

import javafx.application.Application; 
import javafx.beans.property.SimpleDoubleProperty; 
import javafx.event.EventHandler; 
import javafx.scene.chart.CategoryAxis; 
import javafx.scene.chart.NumberAxis; 
import javafx.scene.chart.XYChart; 
import javafx.stage.Stage; 
import javafx.scene.Scene; 
import javafx.scene.chart.LineChart; 
import javafx.scene.input.MouseEvent; 
import javafx.scene.layout.BorderPane; 
import javafx.scene.paint.Color; 
import javafx.scene.shape.LineTo; 
import javafx.scene.shape.MoveTo; 
import javafx.scene.shape.Path; 
import javafx.scene.shape.Rectangle; 

public class Zoom01 extends Application { 

Path path;//Add path for freehand 
BorderPane pane; 
Rectangle rect; 
SimpleDoubleProperty rectinitX = new SimpleDoubleProperty(); 
SimpleDoubleProperty rectinitY = new SimpleDoubleProperty(); 
SimpleDoubleProperty rectX = new SimpleDoubleProperty(); 
SimpleDoubleProperty rectY = new SimpleDoubleProperty(); 

@Override 
public void start(Stage stage) { 

    System.out.println("Java Version    : " + com.sun.javafx.runtime.VersionInfo.getVersion()); 
    System.out.println("Java getHudsonBuildNumber: " + com.sun.javafx.runtime.VersionInfo.getHudsonBuildNumber()); 
    System.out.println("Java getReleaseMilestone : " + com.sun.javafx.runtime.VersionInfo.getReleaseMilestone()); 
    System.out.println("Java getRuntimeVersion : " + com.sun.javafx.runtime.VersionInfo.getRuntimeVersion()); 

    stage.setTitle("Lines plot"); 

    //final CategoryAxis xAxis = new CategoryAxis(); 
    final NumberAxis xAxis = new NumberAxis(1, 12, 1); 
    final NumberAxis yAxis = new NumberAxis(0.53000, 0.53910, 0.0005); 

    yAxis.setTickLabelFormatter(new NumberAxis.DefaultFormatter(yAxis) { 

     @Override 
     public String toString(Number object) { 
      return String.format("%7.5f", object); 
     } 
    }); 


    //final LineChart<String, Number> lineChart = new LineChart<String, Number>(xAxis, yAxis); 
    final LineChart<Number, Number> lineChart = new LineChart<Number, Number>(xAxis, yAxis); 

    //lineChart.setTitle("Stock quotes"); 
    lineChart.setCreateSymbols(false); 
    lineChart.setAlternativeRowFillVisible(false); 
    lineChart.setAnimated(true); 

    XYChart.Series series1 = new XYChart.Series(); 
    //series1.setName("Stock 1"); 
    series1.getData().add(new XYChart.Data(1, 0.53185)); 
    series1.getData().add(new XYChart.Data(2, 0.532235)); 
    series1.getData().add(new XYChart.Data(3, 0.53234)); 
    series1.getData().add(new XYChart.Data(4, 0.538765)); 
    series1.getData().add(new XYChart.Data(5, 0.53442)); 
    series1.getData().add(new XYChart.Data(6, 0.534658)); 
    series1.getData().add(new XYChart.Data(7, 0.53023)); 
    series1.getData().add(new XYChart.Data(8, 0.53001)); 
    series1.getData().add(new XYChart.Data(9, 0.53589)); 
    series1.getData().add(new XYChart.Data(10, 0.53476)); 
    series1.getData().add(new XYChart.Data(11, 0.530123)); 
    series1.getData().add(new XYChart.Data(12, 0.53035)); 


    pane = new BorderPane(); 
    pane.setCenter(lineChart); 
    //Scene scene = new Scene(lineChart, 800, 600); 
    Scene scene = new Scene(pane, 800, 600); 
    lineChart.getData().addAll(series1); 

    stage.setScene(scene);   

    path = new Path(); 
    path.setStrokeWidth(1); 
    path.setStroke(Color.BLACK); 

    scene.setOnMouseClicked(mouseHandler); 
    scene.setOnMouseDragged(mouseHandler); 
    scene.setOnMouseEntered(mouseHandler); 
    scene.setOnMouseExited(mouseHandler); 
    scene.setOnMouseMoved(mouseHandler); 
    scene.setOnMousePressed(mouseHandler); 
    scene.setOnMouseReleased(mouseHandler); 

    //root.getChildren().add(lineChart); 
    pane.getChildren().add(path); 

    rect = new Rectangle(); 
    rect.setFill(Color.web("blue", 0.1)); 
    rect.setStroke(Color.BLUE); 
    rect.setStrokeDashOffset(50); 

    rect.widthProperty().bind(rectX.subtract(rectinitX)); 
    rect.heightProperty().bind(rectY.subtract(rectinitY)); 
    pane.getChildren().add(rect); 

    stage.show(); 
} 
EventHandler<MouseEvent> mouseHandler = new EventHandler<MouseEvent>() { 

    @Override 
    public void handle(MouseEvent mouseEvent) { 

     if (mouseEvent.getEventType() == MouseEvent.MOUSE_PRESSED) { 
      rect.setX(mouseEvent.getX()); 
      rect.setY(mouseEvent.getY()); 
      rectinitX.set(mouseEvent.getX()); 
      rectinitY.set(mouseEvent.getY()); 
     } else if (mouseEvent.getEventType() == MouseEvent.MOUSE_DRAGGED) { 
      rectX.set(mouseEvent.getX()); 
      rectY.set(mouseEvent.getY()); 
     } else if (mouseEvent.getEventType() == MouseEvent.MOUSE_RELEASED) { 

      System.out.println("Zoom bounds : [" + rectinitX.get()+", "+rectinitY.get()+"] ["+ rectX.get()+", "+rectY.get()+"]");     
      System.out.println("TODO: Determine bound ranges according these zoom coordinates.\n"); 

      // TODO: Determine bound ranges according this zoom coordinates. 
      //LineChart<String, Number> lineChart = (LineChart<String, Number>) pane.getCenter(); 
      LineChart<Number, Number> lineChart = (LineChart<Number, Number>) pane.getCenter(); 

      // Zoom in Y-axis by changing bound range. 
      NumberAxis yAxis = (NumberAxis) lineChart.getYAxis(); 
      yAxis.setLowerBound(0.532); 
      yAxis.setUpperBound(0.538); 

      // Zoom in X-axis by removing first and last data values. 
      // Note: Maybe better if categoryaxis is replaced by numberaxis then setting the 
      // LowerBound and UpperBound will be avaliable. 
      /* 
      XYChart.Series series1 = lineChart.getData().get(0); 
      if (!series1.getData().isEmpty()) { 
       series1.getData().remove(0); 
       series1.getData().remove(series1.getData().size() - 1); 
      } 
      */ 

      NumberAxis xAxis = (NumberAxis) lineChart.getXAxis(); 
      System.out.println("(a) xAxis.getLowerBound() "+xAxis.getLowerBound()+" "+xAxis.getUpperBound()); 
      double Tgap = xAxis.getWidth()/(xAxis.getUpperBound() - xAxis.getLowerBound()); 
      double newXlower, newXupper; 
      newXlower = (rectinitX.get()/Tgap)+xAxis.getLowerBound(); 

      newXupper = (rectX.get()/Tgap)+xAxis.getLowerBound(); 
      if (newXupper > xAxis.getUpperBound()) 
       newXupper = xAxis.getUpperBound(); 

      xAxis.setLowerBound(newXlower); 
      xAxis.setUpperBound(newXupper); 

      System.out.println("(b) xAxis.getLowerBound() "+xAxis.getLowerBound()+" "+xAxis.getUpperBound()); 

      // Hide the rectangle 
      rectX.set(0); 
      rectY.set(0); 
     } 
    } 
    }; 

    public static void main(String[] args) { 
    launch(args); 
    } 
    } 

Answer 1

將鼠標事件附加到場景。所以mouseEvent.getX()給你相對於場景的座標。但是你的公式使用它們作爲相對於xAxis節點的座標。您需要考慮場景中的xAxis位置。

介紹下一個方法：

// summ layout shift against parent until we ascend to scene 
private static double getSceneShift(Node node) { 
    double shift = 0; 
    do { 
     shift += node.getLayoutX(); 
     node = node.getParent(); 
    } while (node != null); 
    return shift; 
} 

，並相應地改變你的計算：

 double xAxisShift = getSceneShift(xAxis); 
     newXlower = ((rectinitX.get() - xAxisShift)/Tgap) + xAxis.getLowerBound(); 
     newXupper = ((rectX.get() - xAxisShift)/Tgap) + xAxis.getLowerBound();