如何自定义xtext生成的Eclipse编辑器

Question

在我当前的项目中，我试图在我的编辑器中提供大纲视图。我在xtext中编写了以下语法：

Model:
    (vocSpec=VocSpec );


VocSpec:
    structKeyword = 'structs' ':' (structs+=Struct)+
    resourceKeyword = 'resources:'  
     sensorKeyword ='sensors' ':'
    periodicSensorKeyword ='periodicSensors' ':' (periodicSensors+=PeriodicSensors)*
    eventDrivenSensorKeyword ='eventDrivenSensors' ':' (eventSensors+=EventSensors)*
    requestBasedSensorKeyword ='requestBasedSensors' ':' (requestSensors+=RequestSensors)*
    tagKeyword ='tags' ':' (tags+=Tags)*
    actuatorsKeyword ='actuators' ':' (actuators+=Actuator)*
    storageKeyword ='storages' ':' (storageService+=StorageService)* 
    ;

Struct:
    name=ID (fields+=Field)+;

Field:
    name=ID ':' type+=Type ';'
;

/* Periodic Sensor Definition */
PeriodicSensors:
    sensorName=EntityName
    (generateInfo+=Generate)+
    'sample' 'period' INT 'for' INT ';'
;

/* Event Driven Sensor Definition */
EventSensors:
    sensorName=EntityName
    (generateInfo+=Generate)+
    'onCondition' (eventConditions+=EventConditions) ';';

/* Request Based Sensor Definition */
RequestSensors:
    sensorName=EntityName
    ((DataAccess+=DataAccess))*;

/* Tag Definition */
Tags:
    sensorName=EntityName
    (generateInfo+=Generate)+;

EventConditions:
    name=ID ('>' | '<' | '=')* (intValue=INT) (nameUnit=Unit) (',' eventConditions+=EventConditions)?
;

OPERATOR:
    opt='>' | opt='<' | opt='=';

EntityName:
    (name=ID);

Generate:
    'generate' sourceName=SourceName ':' type=Type ';';

SourceName:
    name=ID;

Actuator:
    actuatorName=EntityName ((actions+=Action))*;

Action:
    'action' actionName=ActionName '(' (parameters+=Parameters)* ')' ';';

ActionName:
    name=ID;

Parameters:
    parameterName=ParameterName ':' type=Type;

ParameterName:
    name=ID;

/*  Storage Service Definition  */
StorageService:
    storageServiceName=EntityName
    ((dataAccesses+=DataAccess))*;

DataAccess:
    'generate' sourceName=SourceName ':' dataAccessType=Type
    'accessed-by' dataItem=ID ':' type=Type ';'
    ((actions+=Action))*;

/* Type Definition */
Type:
    (primitiveDataType=PrimitiveDataType);

Unit:
    name='PPM' | name='miliseconds' | name='seconds' | name='minutes' | name='ppm';

PrimitiveDataType:
    INTEGER='Integer' | BOOLEAN='boolean' | STRING='String' | LONG='long' | DOUBLE='double' | structDef=[Struct];

通过上述语法，我编写了以下规范：

此处Sensors 类型 Resource，periodicSensors 类型 Sensors。 Tags类型为Resource，actuators类型为resources。  因此，如果我将其转换为大纲视图，则大纲视图应如下所示：

但是，使用上面的语法，我在xtext生成的编辑器中得到以下大纲视图。如何在xtext编辑器中获得所需的大纲视图。我想我必须修改我的xtext语法，如上所述？ /其他的事情。请建议