JavaFX Dialog (3)

除了Alert類別之外，另外尚有ChoiceDialog與TextInputDialog類別，皆繼承自Dialog類別，分別在對話盒中顯示選項方塊 (Choice Box) 與文字欄位 (Text Field)，此外亦可以Dialog類別自訂對話盒。

以下範例示範以TextInputDialog建立文字欄位之對話盒，較之前以getDialogPane()的setContent()或setExpandableContent()方法將自訂物件置於對話盒的方式為簡單：

TextInputDialog dialog = new TextInputDialog();
dialog.setTitle("Text Input Dialog");
dialog.setHeaderText(null);
dialog.setContentText("Username:");

dialog.showAndWait().ifPresent(result -> {
  System.out.println("Username: " + result);
});     
...

【執行結果】

以下範例並加入setHeaderText()方法設定標題文字：

TextInputDialog dialog = new TextInputDialog();
dialog.setTitle("Text Input Dialog");
dialog.setHeaderText("示範以setHeaderText()方法設定標題文字。");
dialog.setContentText("Username:");

dialog.showAndWait().ifPresent(result -> {
  System.out.println("Username: " + result);
});     
...

【執行結果】

以下範例示範以ChoiceDialog建立選項方塊之對話盒，並示範將作業系統的所有字型置於選項方塊之中：

// 取得作業系統的所有字型
List<String> fonts = Font.getFamilies();

// 以字型建立選項方塊對話盒
ChoiceDialog<String> dialog = 
  new ChoiceDialog<>(fonts.get(0), fonts);
dialog.setTitle("Choice Dialog");
dialog.setHeaderText(null);
dialog.setContentText("Fonts:");

dialog.showAndWait().ifPresent(result -> {
  System.out.println("Font: " + result);
});     
...

【執行結果】

除此之外，亦可以Dialog類別自訂對話盒，請參考以下範例，分別加入文字欄位、修改對話盒圖示與按鈕類型組合：

Dialog<Pair<String, String>> dialog = new Dialog<>();
dialog.setTitle("Custom Dialog");
dialog.setHeaderText(null);
dialog.setGraphic(new ImageView(
  new Image(getClass().getResourceAsStream("images/info.png"))));

// 自訂按鈕類型組合
ButtonType button1 = new ButtonType("OK", ButtonData.OK_DONE);
ButtonType button2 = new ButtonType("Cancel", ButtonData.CANCEL_CLOSE);

dialog.getDialogPane().getButtonTypes().addAll(button1, button2);

Label label1 = new Label("Username:");
Label label2 = new Label("Password:");

final TextField textfield = new TextField();
textfield.setText("");
textfield.setTooltip(new Tooltip("Username"));

final PasswordField passwordfield = new PasswordField();
passwordfield.setText("Athena");
passwordfield.setPrefColumnCount(15);
passwordfield.setPromptText("Please enter your password.");
passwordfield.setTooltip(new Tooltip("Password"));

GridPane gridpane = new GridPane();
gridpane.setAlignment(Pos.CENTER);
gridpane.setHgap(10);
gridpane.setVgap(10);
gridpane.setPadding(new Insets(5, 5, 5, 5));

gridpane.add(label1, 0, 0);
gridpane.add(label2, 0, 1);

gridpane.add(textfield, 1, 0);
gridpane.add(passwordfield, 1, 1);

Button btnOK = (Button) dialog.getDialogPane().lookupButton(button1);
btnOK.setDisable(true);

textfield.textProperty().addListener(
  (observable, oldValue, newValue) -> {
  
  btnOK.setDisable(newValue.trim().isEmpty());
});

// 將自訂物件置於對話盒中
dialog.getDialogPane().setContent(gridpane);

dialog.setResultConverter(buttontype -> {
  if (buttontype == button1) {
    return new Pair<>(textfield.getText(), passwordfield.getText());
  }
  return null;
});

dialog.showAndWait().ifPresent(result -> {
  System.out.println("Username: " + result.getKey());
  System.out.println("Password: " + result.getValue());
});
...

【執行結果】

【參考資料】

[1] Java Official Web Site：http://www.oracle.com/technetwork/java/index.html
[2] JavaFX：http://www.oracle.com/technetwork/java/javafx
[3] JavaFX 8.0 API Specification.
[4] Java Platform, Standard Edition 8 API Specification.

© Chia-Hui Huang