[qt6][ui] Limit useless calls to recentProjectFiles when opening dialogs

This prevents emitting signals that lead to countless updates when a
single one is necessary, thus causing some freezes in the interface.

Author: cbentejac

meshroom/ui/app.py

@@ -354,6 +354,7 @@ def _recentProjectFiles(self):
                 p = {"path": p, "thumbnail": thumbnail}
                 projects.append(p)
         settings.endArray()
+        settings.endGroup()
         return projects
 
     @Slot(str)
@@ -393,6 +394,7 @@ def addRecentProjectFile(self, projectFile):
             settings.setArrayIndex(i)
             settings.setValue("filepath", p)
         settings.endArray()
+        settings.endGroup()
         settings.sync()
 
         self.recentProjectFilesChanged.emit()

meshroom/ui/qml/main.qml

@@ -76,13 +76,19 @@ ApplicationWindow {
 
     function initFileDialogFolder(dialog, importImages = false) {
         let folder = ""
-        let projects = MeshroomApp.recentProjectFiles
+        let project = ""
+        try {
+            // The list of recent projects might be empty, hence the try/catch
+            project = MeshroomApp.recentProjectFiles[0]["path"]
+        } catch (error) {
+            console.info("The list of recent projects is currently empty.")
+        }
         let currentItem = mainStack.currentItem
 
         if (currentItem instanceof Homepage) {
             // From the homepage, take the folder from the most recent project (no prior check on its existence)
-            if (projects.length > 0 && Filepath.exists(projects[0]["path"])) {
-                folder = Filepath.stringToUrl(Filepath.dirname(projects[0]["path"]))
+            if (project != "" && Filepath.exists(project)) {
+                folder = Filepath.stringToUrl(Filepath.dirname(project))
             }
         } else {
 
@@ -97,8 +103,8 @@ ApplicationWindow {
             } else {
                 // If the currently opened project has not been saved, the dialog will open in the same
                 // folder as the most recent project if it exists; otherwise, it will not be set
-                if (projects.length > 0 && Filepath.exists(projects[0]["path"])) {
-                    folder = Filepath.stringToUrl(Filepath.dirname(projects[0]["path"]))
+                if (project != "" && Filepath.exists(project)) {
+                    folder = Filepath.stringToUrl(Filepath.dirname(project))
                 }
             }