阻止JavaFX中的手風琴坍塌

Question

有沒有一種簡單的方法可以防止JavaFX 2.1中的手風琴完全崩潰？我手風琴有幾個條目，但如果用戶點擊活躍的手風琴條目，它會摺疊手風琴。

我大概可以使用鼠標點擊偵聽器來檢查檢查並採取相應的行動，但這種感覺應該比完成更簡單。

Answer 1

將偵聽器添加到當前展開的手風琴窗格中，並通過修改其可摺疊屬性來防止它被用戶摺疊。

這裏是一個示例應用程序：

import javafx.application.Application; 
import javafx.application.Platform; 
import javafx.beans.value.*; 
import javafx.scene.Scene; 
import javafx.scene.control.*; 
import javafx.scene.layout.*; 
import javafx.stage.Stage; 

public class AccordionSample extends Application { 
    public static void main(String[] args) { launch(args); } 
    @Override public void start(Stage primaryStage) { 
    // create some titled panes to go in an accordion. 
    TitledPane adminPane = new TitledPane("Animals", 
     VBoxBuilder.create().style("-fx-padding: 10").spacing(10).children(
     ButtonBuilder.create().text("Zebra").maxWidth(Double.MAX_VALUE).build(), 
     ButtonBuilder.create().text("Shrew").maxWidth(Double.MAX_VALUE).build() 
    ).build()    
    ); 
    TitledPane viewPane = new TitledPane("Vegetables", 
     VBoxBuilder.create().style("-fx-padding: 10").spacing(10).children(
     ButtonBuilder.create().text("Eggplant").maxWidth(Double.MAX_VALUE).build(), 
     ButtonBuilder.create().text("Carrot").maxWidth(Double.MAX_VALUE).build() 
    ).build()    
    ); 

    // create an accordion, ensuring the currently expanded pane can not be clicked on to collapse. 
    Accordion accordion = new Accordion(); 
    accordion.getPanes().addAll(adminPane, viewPane); 
    accordion.expandedPaneProperty().addListener(new ChangeListener<TitledPane>() { 
     @Override public void changed(ObservableValue<? extends TitledPane> property, final TitledPane oldPane, final TitledPane newPane) { 
     if (oldPane != null) oldPane.setCollapsible(true); 
     if (newPane != null) Platform.runLater(new Runnable() { @Override public void run() { 
      newPane.setCollapsible(false); 
     }}); 
     } 
    }); 
    for (TitledPane pane: accordion.getPanes()) pane.setAnimated(false); 
    accordion.setExpandedPane(accordion.getPanes().get(0)); 

    // layout the scene. 
    StackPane layout = new StackPane(); 
    layout.setStyle("-fx-padding: 10; -fx-background-color: cornsilk;"); 
    layout.getChildren().add(accordion); 
    primaryStage.setScene(new Scene(layout)); 
    primaryStage.show(); 
    } 
} 

Answer 2

這裏是確保手風琴將永遠不會完全崩潰另一種解決方案。與@jewelsea偉大的原始答案的區別很小 - 我不喜歡這樣一個事實，即默認向下的箭頭正從露天手風琴TitledPane的臉上消失，因爲它的「可摺疊」屬性被設置爲false。爲了讓我的界面更加「自然」，我玩了更多。

/* Make sure the accordion can never be completely collapsed */ 
    accordeon.expandedPaneProperty().addListener((ObservableValue<? extends TitledPane> observable, TitledPane oldPane, TitledPane newPane) -> { 
     Boolean expand = true; // This value will change to false if there's (at least) one pane that is in "expanded" state, so we don't have to expand anything manually 
     for(TitledPane pane: accordeon.getPanes()) { 
      if(pane.isExpanded()) { 
       expand = false; 
      } 
     } 
     /* Here we already know whether we need to expand the old pane again */ 
     if((expand == true) && (oldPane != null)) { 
      Platform.runLater(() -> { 
       accordeon.setExpandedPane(oldPane); 
      }); 
     } 
    });