ScalingService: 1st pass of the refactoring via signals instead of nested bindings for better efficienty and compatibility with old versions of Qt

Services/ScalingService.qml

@@ -1,17 +1,43 @@
 pragma Singleton
 
+import QtQuick
 import Quickshell
 import qs.Commons
 
 Singleton {
   id: root
 
+  // Cache for current scales - updated via signals
+  property var currentScales: ({})
+
+  // Signal emitted when scale changes
+  signal scaleChanged(string screenName, real scale)
+
+  Component.onCompleted: {
+    Logger.log("Scaling", "Service started")
+  }
+
+  Connections {
+    target: Settings
+    function onSettingsLoaded() {
+      // Initialize cache from Settings once they are loaded on startup
+      var monitors = Settings.data.ui.monitorsScaling || []
+      for (var i = 0; i < monitors.length; i++) {
+        if (monitors[i].name && monitors[i].scale !== undefined) {
+          currentScales[monitors[i].name] = monitors[i].scale
+          root.scaleChanged(monitors[i].name, monitors[i].scale)
+          Logger.log("Scaling", "Caching scaling for", monitors[i].name, ":", monitors[i].scale)
+        }
+      }
+    }
+  }
+
   // -------------------------------------------
   // Manual scaling via Settings
-  function scale(aScreen) {
+  function getScreenScale(aScreen) {
     try {
       if (aScreen !== undefined && aScreen.name !== undefined) {
-        return getMonitorScale(aScreen.name)
+        return getScreenScaleByName(aScreen.name)
       }
     } catch (e) {
 
@@ -21,15 +47,12 @@ Singleton {
   }
 
   // -------------------------------------------
-  function getMonitorScale(aScreenName) {
+  // Get scale from cache for better performance
+  function getScreenScaleByName(aScreenName) {
     try {
-      var monitors = Settings.data.ui.monitorsScaling
-      if (monitors !== undefined) {
-        for (var i = 0; i < monitors.length; i++) {
-          if (monitors[i].name !== undefined && monitors[i].name === aScreenName) {
-            return monitors[i].scale
-          }
-        }
+      var scale = currentScales[aScreenName]
+      if ((scale !== undefined) && (scale != null)) {
+        return scale
       }
     } catch (e) {
 
@@ -39,34 +62,69 @@ Singleton {
   }
 
   // -------------------------------------------
-  function setMonitorScale(aScreenName, scale) {
+  function setScreenScale(aScreen, scale) {
     try {
-      var monitors = Settings.data.ui.monitorsScaling
-      if (monitors !== undefined) {
-        for (var i = 0; i < monitors.length; i++) {
-          if (monitors[i].name !== undefined && monitors[i].name === aScreenName) {
-            monitors[i].scale = scale
-            return
-          }
-        }
+      if (aScreen !== undefined && aScreen.name !== undefined) {
+        return setScreenScaleByName(aScreen.name, scale)
       }
-      monitors.push({
-                      "name": aScreenName,
-                      "scale": scale
-                    })
     } catch (e) {
 
       //Logger.warn(e)
     }
   }
 
+  // -------------------------------------------
+  function setScreenScaleByName(aScreenName, scale) {
+    try {
+      // Check if scale actually changed
+      var oldScale = currentScales[aScreenName] || 1.0
+      if (oldScale === scale) {
+        return
+        // No change needed
+      }
+
+      // Update cache directly
+      currentScales[aScreenName] = scale
+
+      // Update Settings with immutable update for proper persistence
+      var monitors = Settings.data.ui.monitorsScaling || []
+      var found = false
+
+      var newMonitors = monitors.map(function (monitor) {
+        if (monitor.name === aScreenName) {
+          found = true
+          return {
+            "name": aScreenName,
+            "scale": scale
+          }
+        }
+        return monitor
+      })
+
+      if (!found) {
+        newMonitors.push({
+                           "name": aScreenName,
+                           "scale": scale
+                         })
+      }
+
+      // Use slice() to ensure Settings detects the change
+      Settings.data.ui.monitorsScaling = newMonitors.slice()
+
+      // Emit signal for components to react
+      root.scaleChanged(aScreenName, scale)
+
+      Logger.log("Scaling", "Scale changed for", aScreenName, "to", scale)
+    } catch (e) {
+      Logger.warn("Scaling", "Error setting scale:", e)
+    }
+  }
+
   // -------------------------------------------
   // Dynamic scaling based on resolution
-
   // Design reference resolution (for scale = 1.0)
   readonly property int designScreenWidth: 2560
   readonly property int designScreenHeight: 1440
-
   function dynamicScale(aScreen) {
     if (aScreen != null) {
       var ratioW = aScreen.width / designScreenWidth