anchor.diff:        }
       }
   
  -    final _Attribute package = manifest.firstAttribute('package');
  +    final _Attribute? package = manifest.firstAttribute('package');
       // "io.flutter.examples.hello_world" (Raw: "io.flutter.examples.hello_world")
  -    final String packageName = package.value.substring(1, package.value.indexOf('" '));
  +    final String? packageName = package?.value?.substring(1, package.value?.indexOf('" '));
   
       if (launchActivity == null) {
         logger.printError('Error running $packageName. Default activity not found');
         return null;
       }
   
  -    final _Attribute nameAttribute = launchActivity.firstAttribute('android:name');
  +    final _Attribute? nameAttribute = launchActivity.firstAttribute('android:name');
       // "io.flutter.examples.hello_world.MainActivity" (Raw: "io.flutter.examples.hello_world.MainActivity")
  -    final String activityName = nameAttribute
  -        .value.substring(1, nameAttribute.value.indexOf('" '));
  +    final String? activityName = nameAttribute?.value?.substring(1, nameAttribute.value?.indexOf('" '));
   
       // Example format: (type 0x10)0x1
  -    final _Attribute versionCodeAttr = manifest.firstAttribute('android:versionCode');
  +    final _Attribute? versionCodeAttr = manifest.firstAttribute('android:versionCode');
       if (versionCodeAttr == null) {
         logger.printError('Error running $packageName. Manifest versionCode not found');
         return null;
       }
  -    if (!versionCodeAttr.value.startsWith('(type 0x10)')) {
  +    if (versionCodeAttr.value?.startsWith('(type 0x10)') != true) {
         logger.printError('Error running $packageName. Manifest versionCode invalid');
         return null;
       }
  -    final int versionCode = int.tryParse(versionCodeAttr.value.substring(11));
  +    final int? versionCode = versionCodeAttr.value == null ? null : int.tryParse(versionCodeAttr.value!.substring(11));
       if (versionCode == null) {
         logger.printError('Error running $packageName. Manifest versionCode invalid');
         return null;
  
positive.code:     return false;
    }
  
    static ApkManifestData parseFromXmlDump(String data, Logger logger) {
      if (data == null || data.trim().isEmpty) {
        return null;
      }
  
negative.code: /// An application package created from an already built Android APK.
  class AndroidApk extends ApplicationPackage {
    AndroidApk({
      required String id,
      required this.file,
      required this.versionCode,
      required this.launchActivity,
    }) : assert(file != null),
         assert(launchActivity != null),
         super(id: id);
  