Yet another change

Author: ifilot

gui/packaging/config/config.xml.template

@@ -7,6 +7,7 @@
     <StartMenuDir>{{ publisher }}</StartMenuDir>
 
     <!-- Fixed install location (no version folder) -->
+    <ControlScript>installscript.qs</ControlScript>
     <TargetDir>@ApplicationsDir@/{{ publisher }}/{{ progfolder }}</TargetDir>
     <RemoveTargetDir>true</RemoveTargetDir>
 

gui/packaging/config/installscript.qs

@@ -0,0 +1,18 @@
+function Controller() {}
+
+Controller.prototype.TargetDirectoryPageCallback = function() {
+    var page = gui.pageWidgetByObjectName("TargetDirectoryPage");
+
+    // Override the default validation function
+    page.targetDirectoryLineEdit().textChanged.connect(function(dir) {
+        // Always allow the user to continue
+        page.completeChanged();
+    });
+
+    page.isComplete = function() {
+        var dir = page.targetDirectoryLineEdit().text;
+
+        // If the directory exists and has an existing installation, we still allow it
+        return true;
+    };
+};