【发布时间】：2015-03-24 08:39:49
【问题描述】：
我使用scene builder v2.0 创建了一个fxml 布局。我正在修改控制器文件中的图表，即 SampleController.java 文件。我能够使用 .setTitle 方法设置图表标题。我需要动态设置 xAxis (Start, End, Ticks) 和 yAxis 的范围。在 CSS 中，使用 lowerBound 和 upperBound 属性很容易设置。但这是一个永久的解决方案。请提供您宝贵的建议和解决方案。
Main.java：
package application;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Scene;
import javafx.scene.control.SplitPane;
import javafx.stage.Stage;
public class Main extends Application{
@Override
public void start(Stage primaryStage) {
try {
SplitPane root = (SplitPane)FXMLLoader.load(getClass().getResource("Sample.fxml"));
Scene scene = new Scene(root,800,400);
scene.getStylesheets().add(getClass().getResource("application.css").toExternalForm());
primaryStage.setScene(scene);
primaryStage.show();
} catch(Exception e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
launch(args);
}
}
Sample.fxml
<?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.control.*?>
<?import java.lang.*?>
<?import javafx.scene.chart.*?>
<?import javafx.scene.layout.*?>
<?import javafx.scene.layout.BorderPane?>
<SplitPane dividerPositions="0.7892976588628763" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="400.0" minWidth="800.0" prefHeight="400.0" prefWidth="800.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1" fx:controller="application.SampleController">
<items>
<AnchorPane minHeight="0.0" minWidth="0.0" prefHeight="160.0" prefWidth="100.0">
<children>
<LineChart fx:id="Ch" alternativeColumnFillVisible="true" layoutX="14.0" prefHeight="398.0" prefWidth="500.0">
<xAxis>
<NumberAxis side="BOTTOM" />
</xAxis>
<yAxis>
<NumberAxis layoutX="10.0" side="LEFT" />
</yAxis>
</LineChart>
</children></AnchorPane>
<AnchorPane minHeight="0.0" minWidth="0.0" prefHeight="160.0" prefWidth="100.0">
<children>
<Button fx:id="sine" layoutX="21.0" layoutY="101.0" mnemonicParsing="false" text="Sinusoidal" />
<Button fx:id="triangle" layoutX="21.0" layoutY="148.0" mnemonicParsing="false" prefHeight="25.0" prefWidth="70.0" text="Triangle" />
<Button fx:id="square" layoutX="21.0" layoutY="187.0" mnemonicParsing="false" prefHeight="25.0" prefWidth="70.0" text="Square" />
<Label layoutX="20.0" layoutY="40.0" prefHeight="17.0" prefWidth="83.0" text="Controls" />
</children></AnchorPane>
</items>
</SplitPane>
SampleController.java
package application;
import java.net.URL;
import java.util.ResourceBundle;
import javafx.animation.Animation;
import javafx.animation.KeyFrame;
import javafx.animation.Timeline;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.chart.Axis;
import javafx.scene.chart.LineChart;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart;
import javafx.scene.chart.XYChart.Series;
import javafx.scene.control.Button;
import javafx.util.Duration;
public class SampleController implements Initializable {
final NumberAxis xAxis = new NumberAxis(0,24,3);
final NumberAxis yAxis = new NumberAxis(0,1,0.1);
@FXML // fx:id="Ch"
private LineChart<Number, Number> Ch= new LineChart<>(xAxis, yAxis); // No use of using a constructor.
@FXML// fx:id="sine"
private Button sine; // Value injected by FXMLLoader
@FXML// fx:id="triangle"
private Button triangle; // Value injected by FXMLLoader
@FXML// fx:id="Square"
private Button square; // Value injected by FXMLLoader
@Override // This method is called by the FXMLLoader when initialization is complete
public void initialize(URL fxmlFileLocation, ResourceBundle resources) {
assert Ch != null : "fx:id=\"Ch\" was not injected: check your FXML file 'sample.fxml'.";
// initialize your logic here: all @FXML variables will have been injected
sine.setOnAction(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
System.out.println("Sinusoidal Signal Selected /n/n");
}
});
triangle.setOnAction(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
System.out.println("Triangle Signal Selected /n/n");
}
});
square.setOnAction(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
System.out.println("Square Signal Selected /n/n");
}
});
//Ch = new LineChart<>(xAxis, yAxis); // This sadly loads a new chart but is not visible
Ch.setTitle("PiScope Demo");
//Need to set xAxis range Dynamically
//Need to set yAxis range Dynamically
/*
* In CSS we can use lowerBound and upperBound Property.
* */
}
}
【问题讨论】：
-
你试过getXAxis 并调用 set tickUnit 和 bounds 方法吗？请注意，您可能必须将其转换为 ValueAxis。我也不知道你为什么要在控制器文件中重新创建轴和图表。
-
@brian 无法使用 getXAxis 方法设置 Axis。我正在做一个电子项目，需要动态更改轴以在正确的位置获得电压或频率。
-
好吧，我认为 james_d 有适合您的方法，但我的建议是没有 fx:id 作为轴，您仍然可以从图表中获得对轴的引用。获得参考后，您可以设置范围和刻度单位。