DankMaterialShell/quickshell/Common/OSDManager.qml

pragma Singleton
pragma ComponentBehavior: Bound

import Quickshell
import QtQuick

Singleton {
    id: osdManager

    property var currentOSDsByScreen: ({})

    Timer {
        id: screensChangedDelayTimer
        interval: 3000 // 3 seconds
        repeat: false
        onTriggered: {
            const activeNames = {};
            for (let i = 0; i < Quickshell.screens.length; i++)
                activeNames[Quickshell.screens[i].name] = true;
            for (const screenName in osdManager.currentOSDsByScreen) {
                if (activeNames[screenName])
                    continue;
                osdManager.currentOSDsByScreen[screenName] = null;
            }
        }
    }
    Connections {
        target: Quickshell
        function onScreensChanged() {
            screensChangedDelayTimer.restart();
        }
    }

    function showOSD(osd) {
        if (!osd || !osd.screen)
            return;
        const screenName = osd.screen.name;
        const currentOSD = currentOSDsByScreen[screenName];

        if (currentOSD && currentOSD !== osd) {
            if (typeof currentOSD.hide === "function") {
                try {
                    currentOSD.hide();
                } catch (e) {
                    currentOSDsByScreen[screenName] = null;
                }
            } else {
                currentOSDsByScreen[screenName] = null;
            }
        }

        currentOSDsByScreen[screenName] = osd;
    }
}