| Java |
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| public class Main extends Application {
private double X=-2;
@FXML LineChart<Number,Number> lineChart;
@Override
public void start(Stage primaryStage) throws Exception{
Parent root = FXMLLoader.load(getClass().getResource("sample.fxml"));
primaryStage.setScene(new Scene(root, 460, 325));
XYChart.Series<Number,Number> series = new XYChart.Series();
while(X<3){
series.getData().add(new XYChart.Data<>(X,MathV.f(X)));
System.out.println(X +": "+MathV.f(X));
X+=0.5;
}
lineChart.
getData(). // NullPointerException
add(series);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
} |
|
| XML |
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| <?xml version="1.0" encoding="UTF-8"?>
<?import javafx.scene.chart.LineChart?>
<?import javafx.scene.chart.NumberAxis?>
<?import javafx.scene.control.Button?>
<?import javafx.scene.control.TextField?>
<?import javafx.scene.layout.AnchorPane?>
<AnchorPane id="AnchorPane" maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="325.0" prefWidth="460.0" xmlns="http://javafx.com/javafx/8.0.102" xmlns:fx="http://javafx.com/fxml/1" fx:controller="sample.Controller">
<children>
<Button fx:id="button" layoutX="85.0" layoutY="12.0" mnemonicParsing="false" onAction="#onClickMethod" prefHeight="52.0" prefWidth="93.0" text="Click Me!" />
<TextField fx:id="text" layoutX="19.0" layoutY="63.0" prefHeight="25.0" prefWidth="159.0" text="Введите точность" />
<TextField fx:id="textx1" layoutX="19.0" layoutY="13.0" prefHeight="25.0" prefWidth="66.0" text="x1 = " />
<TextField fx:id="textx2" layoutX="19.0" layoutY="38.0" prefHeight="25.0" prefWidth="66.0" text="x2 =" />
<LineChart fx:id="Chart" layoutX="5.0" layoutY="91.0" prefHeight="230.0" prefWidth="448.0" title="График функции">
<xAxis>
<NumberAxis side="BOTTOM" />
</xAxis>
<yAxis>
<NumberAxis side="LEFT" />
</yAxis>
</LineChart>
</children>
</AnchorPane> |
|
lineChart.getData().add(series); NullPointerException. Если @FXML LineChart<Number,Number> lineChart;
создать new LineChart то график не строиться но компилируется. Как исправить?
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