slint/internal/compiler/widgets/qt/listview.slint

// Copyright © SixtyFPS GmbH <info@slint.dev>
// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-1.1 OR LicenseRef-Slint-commercial

import { ScrollView  } from "std-widgets-impl.slint";

export component ListView inherits ScrollView {
    @children
}

component StandardListViewBase inherits ListView {
    in property <[StandardListViewItem]> model;
    in-out property <int> current-item: -1;

    callback current-item-changed(/* current-item */ int);
    callback item-pointer-event(/* item-index */int,  /* event */ PointerEvent, /* absolute mouse position */ Point);

    public function set-current-item(index: int) {
        if(index < 0 || index >= model.length) {
            return;
        }

        root.current-item = index;
        root.current-item-changed(current-item);

        if(current-item-y < 0) {
            self.viewport-y += 0 - current-item-y;
        }

        if(current-item-y + item-height > self.visible-height) {
            self.viewport-y -= current-item-y + item-height - self.visible-height;
        }
    }

    private property <length> item-height: self.viewport-height / self.model.length;
    private property <length> current-item-y: self.viewport-y + current-item * item-height;

    for item[i] in root.model : NativeStandardListViewItem {
        item: item;
        index: i;
        is-selected: root.current-item == i;
        has-hover: i-touch-area.has-hover;

        i-touch-area := TouchArea {
            clicked => {
                set-current-item(i);
            }

            pointer-event(pe) => {
                root.item-pointer-event(i, pe, {
                    x: self.absolute-position.x + self.mouse-x - root.absolute-position.x,
                    y: self.absolute-position.y + self.mouse-y - root.absolute-position.y,
                });
            }
        }
    }
}

export component StandardListView inherits StandardListViewBase {
    FocusScope {
        key-pressed(event) => {
            if (event.text == Key.UpArrow) {
                root.set-current-item(root.current-item - 1);
                return accept;
            } else if (event.text == Key.DownArrow) {
                root.set-current-item(root.current-item + 1);
                return accept;
            }
            reject
        }
    }
}