javafx - WizardPane：禁用屏幕上的“上一个”按钮

Question

如何禁用 ControlsFX 屏幕上的“上一个”按钮WizardPane？我正在尝试使用这种方法prev.setDisable(true)，但我所拥有的是NullPointerException.

public class MainApp extends Application {
    Wizard wizard = new Wizard();

    WizardPane1 page1 = new WizardPane1();

    WizardPane page2 = new WizardPane();

    WizardPane page3 = new WizardPane() {
        @Override
        public void onEnteringPage(Wizard wizard) {
            Node prev = lookupButton(ButtonType.PREVIOUS);
            prev.setDisable(true);
        }
    };

    page1.setContent(page1.getInit());

    wizard.setFlow(new LinearFlow(page1, page2, page3));
    wizard.showAndWait();

}

public class WizardPane1 extends WizardPane {
      public void initWizard() {}
}

Answer 1

这将禁用该按钮。

@Override 
public void onEnteringPage( Wizard wizard ) { 
     for ( ButtonType type : getButtonTypes() ) {
         if ( type.getButtonData().equals(ButtonBar.ButtonData.BACK_PREVIOUS) ){
             System.out.println("Found Back button");
             previous_button = (Button) lookupButton( type );
             break;
         }
     }

     Platform.runLater(new Runnable() {
         @Override 
         public void run() {        
          previous_button.setDisable(true); 
         }
    });       
}

Answer 2

我没有尝试，但是根据 的源代码，它添加了自己的“上一个”按钮，并且要查找它，您可能需要首先使用以下方法查找Wizard完全相同的引用：ButtonTypeButtonData

WizardPane page3 = new WizardPane()
{
    @Override
    public void onEnteringPage( Wizard wizard )
    {
        for ( ButtonType type : getButtonTypes() )
        {
            if ( type.getButtonData().equals(ButtonBar.ButtonData.BACK_PREVIOUS) )
            {
                Node prev = lookupButton( type );
                prev.setDisable( true );
                break;
            }
        }
    }
};

Answer 3

这是解决方案，它有效:)）

@Override
public void onEnteringPage(Wizard wizard) {

    ObservableList<ButtonType> list = getButtonTypes();

    for (ButtonType type : list) {
        if (type.getButtonData().equals(ButtonBar.ButtonData.BACK_PREVIOUS)) {
            Node prev = lookupButton(type);
            prev.visibleProperty().setValue(Boolean.FALSE);

        }
    }
}