fix null pointer error

Author: TTangNingzhi

.idea/workspace.xml

@@ -23,15 +23,15 @@ dependencies {
 // Configure Gradle IntelliJ Plugin
 // Read more: https://plugins.jetbrains.com/docs/intellij/tools-gradle-intellij-plugin.html
 intellij {
-    version.set("2022.2")
-    type.set("IC") // use IntelliJ Community base, it supports all IDEs
-//    localPath.set( // Example paths for local development
-//        if (System.getProperty("os.name").lowercase().contains("windows")) {
-//            "D:/Program Files/JetBrains/IntelliJ IDEA 2024.3.4.1"
-//        } else {
-//            "/Applications/PyCharm.app/Contents"
-//        }
-//    )
+//    version.set("2022.2")
+//    type.set("IC") // use IntelliJ Community base, it supports all IDEs
+    localPath.set( // Example paths for local development
+        if (System.getProperty("os.name").lowercase().contains("windows")) {
+            "D:/Program Files/JetBrains/IntelliJ IDEA 2024.3.4.1"
+        } else {
+            "/Applications/PyCharm.app/Contents"
+        }
+    )
 }
 
 tasks {

build.gradle.kts

@@ -90,9 +90,9 @@ public void fileOpened(@NotNull FileEditorManager source, @NotNull VirtualFile f
                 editor = source.getSelectedTextEditor();
                 if (editor != null) {
                     editor.getScrollingModel().addVisibleAreaListener(visibleAreaListener);
+                    visibleArea = editor.getScrollingModel().getVisibleArea();
                 }
                 filePath = file.getPath();
-                visibleArea = editor.getScrollingModel().getVisibleArea();
             }
 
             @Override
@@ -101,9 +101,9 @@ public void selectionChanged(@NotNull FileEditorManagerEvent event) {
                 if (event.getNewFile() != null) {
                     if (editor != null) {
                         editor.getScrollingModel().addVisibleAreaListener(visibleAreaListener);
+                        visibleArea = editor.getScrollingModel().getVisibleArea();
                     }
                     filePath = event.getNewFile().getPath();
-                    visibleArea = editor.getScrollingModel().getVisibleArea();
                 }
             }
         });