Java 运行ArrayList时引发空指针异常<;复选框>;
我试图通过下面的代码获取选中的复选框,并以此为基础获取一些值。但当我运行它时,它会抛出一个nullpointerexception。请告诉我如何解决这个问题Java 运行ArrayList时引发空指针异常<;复选框>;,java,arraylist,javafx,Java,Arraylist,Javafx,我试图通过下面的代码获取选中的复选框,并以此为基础获取一些值。但当我运行它时,它会抛出一个nullpointerexception。请告诉我如何解决这个问题 public class GenController implements Initializable { @FXML private Button Generate; @FXML private CheckBox lows; private CheckBox caps; private
public class GenController implements Initializable {
@FXML
private Button Generate;
@FXML
private CheckBox lows;
private CheckBox caps;
private CheckBox numb;
private CheckBox sp;
private CheckBox mcp;
ArrayList<CheckBox> boxes = new ArrayList<CheckBox>();
ArrayList<CheckBox> selected;
public void buttonPressedGen(ActionEvent event) throws Exception {
for (int i = 0; i < boxes.size(); i++) {
if (boxes.get(i).isSelected()) {
System.out.println(boxes.get(i).getText());
}
}
}
@Override
public void initialize(URL location, ResourceBundle resources) {
// TODO Auto-generated method stub
boxes.add(lows);
boxes.add(caps);
boxes.add(numb);
boxes.add(sp);
boxes.add(mcp);
}
}
您需要注释每个
复选框
引用,以便FXMLLoader
注入它们:
@FXML
private CheckBox lows;
@FXML
private CheckBox caps;
@FXML
private CheckBox numb;
@FXML
private CheckBox sp;
@FXML
private CheckBox mcp;
如您所知,
caps
、numb
等都是null
请在代码中标记第54行。非常感谢您_D@checkmate请养成接受答案的习惯!事实证明,它对用户找到类似问题的答案很有用。我本来打算这样做,但它让我留下8分钟来接受:)
@FXML
private CheckBox lows;
@FXML
private CheckBox caps;
@FXML
private CheckBox numb;
@FXML
private CheckBox sp;
@FXML
private CheckBox mcp;