ListViewWindow

ListViewWindow wraps a ListView inside a Window for modal popup behavior (centered floating selector). In SINGLE mode, tapping an item selects and closes the window; in MULTIPLE, the “Confirm” button closes it.

Most methods simply delegate to the internal ListView (configuration and selection query). Use getPanel() if you want the embedded ListView without the popup.

🟡 · Package: dev.crossfly.ui · Extends: Window · Style: WindowStyle (via selectionWindowStyle())

When to use

A modal choice that interrupts the flow (actions menu, item selector, options confirmation).
You want automatic centering and screen-relative sizing without building the Window by hand.

When NOT to use

A list embedded in a screen (not modal) → use ListView directly (or getPanel()).
Thousands of items → use VirtualListView inside your own Window.

Appearance

Centered window occupying a fraction of the screen (widthRatio/heightRatio, default 0.5/0.5), containing the ListView (header + scrollable items + button in MULTIPLE). The background darkens according to the WindowStyle/Skin.

Complete example (copy, paste and run)

package com.exemplo;

import dev.crossfly.ui.*;
import dev.crossfly.ui.layout.*;

/** Runnable main screen. Point the launcher (classname) and run: gradlew :lwjgl3:run */
public class MainWindow extends Window
{
   @Override
   public void onShow() throws Exception
   {
      super.onShow();
      setLayout(new VerticalLayout());

      // The ListViewWindow is a Window (popup): opens with show(), doesn't enter the layout.
      Button abrir = new Button("Escolher vibração");
      abrir.onAction(e -> {
         ListViewWindow pm = new ListViewWindow("Vibrar",
            new String[]{"Curto", "Longo", "Padrão"}, ListViewWindow.ItemType.SINGLE);
         pm.onConfirm(c -> System.out.println("idx = " + pm.getSelectedIndex()));
         pm.show();
      });

      add(.9f, abrir);   // the button that opens the popup enters the layout
   }
}

The snippets below show only the core (what goes inside onShow()). To run them, place them in the MainWindow skeleton above.

Basic usage

// Menu popup (SINGLE): tapping closes and reports the index
ListViewWindow pm = new ListViewWindow("Vibrar", new String[]{"Curto", "Longo", "Padrão"},
      ListViewWindow.ItemType.SINGLE);
pm.onConfirm(c -> System.out.println("idx = " + pm.getSelectedIndex()));
pm.show();

Constructors

Constructor	Description
`ListViewWindow(String[] items, ItemType itemType)`	Popup without title
`ListViewWindow(String title, String[] items, ItemType itemType)`	Popup with title in the header

ListViewWindow.ItemType is its own enum (SINGLE, MULTIPLE) that internally converts to ListView.ItemType.

Properties and customization

Property / method	Type	Default	What it does
`size(float widthRatio, float heightRatio)`	`ListViewWindow`	`0.5, 0.5`	Popup size as a fraction of the screen
`getPanel()`	`ListView`	—	Access to the internal `ListView`
`ItemFactory(ItemFactory)`	`ListViewWindow`	`null`	Custom row factory (note the capital initial)
`computeIdealHeight(int)`	`int`	—	Delegates to `panel.computeIdealHeight`
`title/confirmText/itemStyle/confirmButtonStyle/headerStyle`	`ListViewWindow`	theme	Fluent delegations to the `ListView`

Selection queries (delegated)

getSelectedCount(), getSelectedIndex(), getSelectedText(), getSelectedIndices(), getSelectedTexts(), isSelected(int), getSelectionState().

Callbacks and events

Callback	When it fires
`onConfirm(Component.Action)`	`SINGLE`: on tapping an item (and closes). `MULTIPLE`: on tapping “Confirm” (and closes)

States

Like any Window: use show() to display and hide() to close. The internal ListView already points its closeAction to this::hide, so the selection closes the popup automatically.

Button abrir = new Button("Lista de imagens");
abrir.onAction(e -> {
   ListViewWindow w = new ListViewWindow("Imagens", labels, ListViewWindow.ItemType.SINGLE);
   w.ItemFactory((text, index) -> {
      Image img = new Image(paths[index]);
      ImageView iv = new ImageView(img, UIConstants.ImageSize.RATIO);
      Component row = new Component().style(Styles.component()
         .pressable().ingap(Gap.ofFont(.3f)).autoHeight(Relative.ofFont(3f)));
      row.setLayout(new GridLayout(Position.START, Position.CENTER));
      row.add(.22f, .78f, iv, new Label(text));
      return row;
   });
   w.show();
});

Multi-selection with custom size

ListViewWindow w = new ListViewWindow("Tópicos",
      new String[]{"Java", "Kotlin", "Dart"}, ListViewWindow.ItemType.MULTIPLE)
   .size(.7f, .6f)
   .confirmText("OK");
w.onConfirm(c -> System.out.println(w.getSelectedCount() + " marcados"));
w.show();

Best practices

Adjust size(...) to the content — many items call for a larger heightRatio; few, smaller.
To embed the same list without a popup, call getPanel() and add the returned ListView to your layout.

Common mistakes

Confusing ItemFactory(...) (method, capital I) with the ListView’s itemFactory(...) — here the fluent method starts with a capital by the class’s convention.
Using the wrong enum — in ListViewWindow pass ListViewWindow.ItemType, not ListView.ItemType.