JavaFX default focused button in Alert Dialog

こ雲淡風輕ζ 提交于 2019-12-04 00:13:31

I am not sure if the following is the way to usually do this, but you could change the default button by looking up the buttons and setting the default-behavior yourself:

public boolean showConfirmDialog(String title, String header, String content, AlertType alertType) {
    final Alert alert = new Alert(alertType);
    alert.setTitle(title);
    alert.setHeaderText(header);
    alert.setContentText(content);

    alert.getButtonTypes().clear();
    alert.getButtonTypes().addAll(ButtonType.YES, ButtonType.NO);

    //Deactivate Defaultbehavior for yes-Button:
    Button yesButton = (Button) alert.getDialogPane().lookupButton( ButtonType.YES );
    yesButton.setDefaultButton( false );

    //Activate Defaultbehavior for no-Button:
    Button noButton = (Button) alert.getDialogPane().lookupButton( ButtonType.NO );
    noButton.setDefaultButton( true );

    final Optional<ButtonType> result = alert.showAndWait();
    return result.get() == ButtonType.YES;
}
Sheepy

A simple function thanks to crusam:

private static Alert setDefaultButton ( Alert alert, ButtonType defBtn ) {
   DialogPane pane = alert.getDialogPane();
   for ( ButtonType t : alert.getButtonTypes() )
      ( (Button) pane.lookupButton(t) ).setDefaultButton( t == defBtn );
   return alert;
}

Usage:

final Alert alert = new Alert( 
         AlertType.CONFIRMATION, "You sure?", ButtonType.YES, ButtonType.NO );
if ( setDefaultButton( alert, ButtonType.NO ).showAndWait()
         .orElse( ButtonType.NO ) == ButtonType.YES ) {
   // User selected the non-default yes button
}
José Pereda

If you have a look at (private) ButtonBarSkin class, there is a method called doButtonOrderLayout() that performs the layout of the buttons, based in some default OS behavior.

Inside of it, you can read this:

/* now that all buttons have been placed, we need to ensure focus is set on the correct button. [...] If so, we request focus onto this default button. */

Since ButtonType.YES is the default button, it will be the one focused.

So @ymene answer is correct: you can change the default behavior and then the one focused will be NO.

Or you can just avoid using that method, by setting BUTTON_ORDER_NONE in the buttonOrderProperty(). Now the first button will have the focus, so you need to place first the NO button.

alert.getButtonTypes().setAll(ButtonType.NO, ButtonType.YES);

ButtonBar buttonBar=(ButtonBar)alert.getDialogPane().lookup(".button-bar");
buttonBar.setButtonOrder(ButtonBar.BUTTON_ORDER_NONE);

Note that YES will still have the default behavior: This means NO can be selected with the space bar (focused button), while YES will be selected if you press enter (default button).

Or you can change also the default behavior following @crusam answer.

易学教程内所有资源均来自网络或用户发布的内容,如有违反法律规定的内容欢迎反馈
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!