include/wx/xtistrm.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/xtistrm.h
   3 // Purpose:     streaming runtime metadata information (extended class info)
   4 // Author:      Stefan Csomor
   5 // Modified by:
   6 // Created:     27/07/03
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 2003 Stefan Csomor
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_XTISTRMH__
  13 #define _WX_XTISTRMH__
  14
  15 #if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
  16 #pragma interface "xtistrm.h"
  17 #endif
  18
  19 #include "wx/wx.h"
  20
  21 #if wxUSE_EXTENDED_RTTI
  22
  23 const int wxInvalidObjectID = -2 ;
  24 const int wxNullObjectID = -1 ;
  25
  26 // Filer contains the interfaces for streaming objects in and out of XML,
  27 // rendering them either to objects in memory, or to code.  Note:  We
  28 // consider the process of generating code to be one of *depersisting* the
  29 // object from xml, *not* of persisting the object to code from an object
  30 // in memory.  This distincation can be confusing, and should be kept
  31 // in mind when looking at the property streamers and callback interfaces
  32 // listed below.
  33
  34 /*
  35 Main interfaces for streaming out objects.
  36 */
  37
  38 // ----------------------------------------------------------------------------
  39 // wxPersister
  40 //
  41 // This class will be asked during the streaming-out process about every single
  42 // property or object instance. It can veto streaming out by returning false
  43 // or modify the value before it is streamed-out.
  44 // ----------------------------------------------------------------------------
  45
  46 class wxWriter ;
  47 class wxReader ;
  48
  49 class wxPersister
  50 {
  51 public :
  52     // will be called before an object is written, may veto by returning false
  53     virtual bool BeforeWriteObject( wxWriter *WXUNUSED(writer) , const wxObject *WXUNUSED(object) , const wxClassInfo *WXUNUSED(classInfo) , wxxVariantArray &WXUNUSED(metadata)) { return true ; }
  54
  55     // will be called after this object has been written, may be needed for adjusting stacks
  56     virtual void AfterWriteObject( wxWriter *WXUNUSED(writer)  , const wxObject *WXUNUSED(object) , const wxClassInfo *WXUNUSED(classInfo) ) {}
  57
  58     // will be called before a property gets written, may change the value , eg replace a concrete wxSize by wxSize( -1 , -1 ) or veto
  59     // writing that property at all by returning false
  60     virtual bool BeforeWriteProperty( wxWriter *WXUNUSED(writer)  , const wxPropertyInfo *WXUNUSED(propInfo) , wxxVariant &WXUNUSED(value) )  { return true ; }
  61
  62     // will be called before a property gets written, may change the value , eg replace a concrete wxSize by wxSize( -1 , -1 ) or veto
  63     // writing that property at all by returning false
  64     virtual bool BeforeWriteProperty( wxWriter *WXUNUSED(writer)  , const wxPropertyInfo *WXUNUSED(propInfo) , wxxVariantArray &WXUNUSED(value) )  { return true ; }
  65
  66     // will be called after a property has been written out, may be needed for adjusting stacks
  67     virtual void AfterWriteProperty( wxWriter *WXUNUSED(writer)  , const wxPropertyInfo *WXUNUSED(propInfo) ) {}
  68
  69     // will be called before this delegate gets written
  70     virtual bool BeforeWriteDelegate( wxWriter *WXUNUSED(writer) , const wxObject *WXUNUSED(object),  const wxClassInfo* WXUNUSED(classInfo) , const wxPropertyInfo *WXUNUSED(propInfo) ,
  71         const wxObject *&WXUNUSED(eventSink) , const wxHandlerInfo* &WXUNUSED(handlerInfo) ) { return true ; }
  72
  73     virtual void AfterWriteDelegate( wxWriter *WXUNUSED(writer) , const wxObject *WXUNUSED(object),  const wxClassInfo* WXUNUSED(classInfo) , const wxPropertyInfo *WXUNUSED(propInfo) ,
  74         const wxObject *&WXUNUSED(eventSink) , const wxHandlerInfo* &WXUNUSED(handlerInfo) ) { }
  75 } ;
  76
  77 class wxWriter : public wxObject
  78 {
  79 public :
  80     wxWriter() ;
  81     ~wxWriter() ;
  82
  83     // with this call you start writing out a new top-level object
  84     void WriteObject(const wxObject *object, const wxClassInfo *classInfo , wxPersister *persister , const wxString &name , wxxVariantArray &WXUNUSED(metadata)) ;
  85
  86     //
  87     // Managing the object identity table a.k.a context
  88     //
  89     // these methods make sure that no object gets written twice, because sometimes multiple calls to the WriteObject will be
  90     // made without wanting to have duplicate objects written, the object identity table will be reset manually
  91
  92     virtual void ClearObjectContext() ;
  93
  94     // gets the object Id for a passed in object in the context
  95     int GetObjectID(const wxObject *obj) ;
  96
  97     // returns true if this object has already been written in this context
  98     bool IsObjectKnown( const wxObject *obj ) ;
  99
 100     //
 101     // streaming callbacks
 102     //
 103     // these callbacks really write out the values in the stream format
 104
 105     // begins writing out a new toplevel entry which has the indicated unique name
 106     virtual void DoBeginWriteTopLevelEntry( const wxString &name ) = 0 ;
 107
 108     // ends writing out a new toplevel entry which has the indicated unique name
 109     virtual void DoEndWriteTopLevelEntry( const wxString &name ) = 0 ;
 110
 111     // start of writing an object having the passed in ID
 112     virtual void DoBeginWriteObject(const wxObject *object, const wxClassInfo *classInfo, int objectID , wxxVariantArray &metadata ) = 0 ;
 113
 114     // end of writing an toplevel object name param is used for unique identification within the container
 115     virtual void DoEndWriteObject(const wxObject *object, const wxClassInfo *classInfo, int objectID ) = 0 ;
 116
 117     // writes a simple property in the stream format
 118     virtual void DoWriteSimpleType( wxxVariant &value ) = 0 ;
 119
 120     // start of writing a complex property into the stream (
 121     virtual void DoBeginWriteProperty( const wxPropertyInfo *propInfo ) = 0 ;
 122
 123     // end of writing a complex property into the stream
 124     virtual void DoEndWriteProperty( const wxPropertyInfo *propInfo ) = 0;
 125
 126     virtual void DoBeginWriteElement() = 0 ;
 127     virtual void DoEndWriteElement() = 0 ;
 128     // insert an object reference to an already written object
 129     virtual void DoWriteRepeatedObject( int objectID ) = 0 ;
 130
 131     // insert a null reference
 132     virtual void DoWriteNullObject() = 0 ;
 133
 134     // writes a delegate in the stream format
 135     virtual void DoWriteDelegate( const wxObject *object,  const wxClassInfo* classInfo , const wxPropertyInfo *propInfo ,
 136         const wxObject *eventSink , int sinkObjectID , const wxClassInfo* eventSinkClassInfo , const wxHandlerInfo* handlerIndo ) = 0;
 137 private :
 138
 139     struct wxWriterInternal ;
 140     wxWriterInternal* m_data ;
 141
 142     struct wxWriterInternalPropertiesData ;
 143
 144     void WriteAllProperties( const wxObject * obj , const wxClassInfo* ci , wxPersister *persister, wxWriterInternalPropertiesData * data ) ;
 145     void WriteOneProperty( const wxObject *obj , const wxClassInfo* ci , const wxPropertyInfo* pi , wxPersister *persister , wxWriterInternalPropertiesData *data ) ;
 146     void WriteObject(const wxObject *object, const wxClassInfo *classInfo , wxPersister *persister , bool isEmbedded, wxxVariantArray &metadata ) ;
 147     void FindConnectEntry(const wxEvtHandler * evSource,const wxDelegateTypeInfo* dti, const wxObject* &sink , const wxHandlerInfo *&handler) ;
 148 } ;
 149
 150
 151 /*
 152 Streaming callbacks for depersisting XML to code, or running objects
 153 */
 154
 155 class wxDepersister ;
 156
 157 /*
 158 wxReader handles streaming in a class from a arbitrary format. While walking through
 159 it issues calls out to interfaces to depersist the guts from the underlying storage format.
 160 */
 161
 162 class wxReader : public wxObject
 163 {
 164 public :
 165     wxReader() ;
 166     ~wxReader() ;
 167
 168     // the only thing wxReader knows about is the class info by object ID
 169     wxClassInfo *GetObjectClassInfo(int objectID) ;
 170     bool HasObjectClassInfo( int objectID ) ;
 171     void SetObjectClassInfo(int objectID, wxClassInfo* classInfo);
 172
 173     // Reads the component the reader is pointed at from the underlying format.
 174     // The return value is the root object ID, which can
 175     // then be used to ask the depersister about that object
 176     virtual int ReadObject( const wxString &name , wxDepersister *depersist ) = 0 ;
 177
 178 private :
 179     struct wxReaderInternal;
 180     wxReaderInternal *m_data;
 181 } ;
 182
 183 // This abstract class matches the allocate-init/create model of creation of objects.
 184 // At runtime, these will create actual instances, and manipulate them.
 185 // When generating code, these will just create statements of C++
 186 // code to create the objects.
 187
 188 class wxDepersister
 189 {
 190 public :
 191     // allocate the new object on the heap, that object will have the passed in ID
 192     virtual void AllocateObject(int objectID, wxClassInfo *classInfo, wxxVariantArray &metadata) = 0;
 193
 194     // initialize the already allocated object having the ID objectID with the Create method
 195     // creation parameters which are objects are having their Ids passed in objectIDValues
 196     // having objectId <> wxInvalidObjectID
 197
 198     virtual void CreateObject(int objectID,
 199         const wxClassInfo *classInfo,
 200         int paramCount,
 201         wxxVariant *VariantValues ,
 202         int *objectIDValues ,
 203         const wxClassInfo **objectClassInfos ,
 204         wxxVariantArray &metadata) = 0;
 205
 206     // destroy the heap-allocated object having the ID objectID, this may be used if an object
 207     // is embedded in another object and set via value semantics, so the intermediate
 208     // object can be destroyed after safely
 209     virtual void DestroyObject(int objectID, wxClassInfo *classInfo) = 0;
 210
 211     // set the corresponding property
 212     virtual void SetProperty(int objectID,
 213         const wxClassInfo *classInfo,
 214         const wxPropertyInfo* propertyInfo ,
 215         const wxxVariant &VariantValue) = 0;
 216
 217     // sets the corresponding property (value is an object)
 218     virtual void SetPropertyAsObject(int objectID,
 219         const wxClassInfo *classInfo,
 220         const wxPropertyInfo* propertyInfo ,
 221         int valueObjectId) = 0;
 222
 223     // adds an element to a property collection
 224     virtual void AddToPropertyCollection( int objectID ,
 225         const wxClassInfo *classInfo,
 226         const wxPropertyInfo* propertyInfo ,
 227         const wxxVariant &VariantValue) = 0;
 228
 229     // sets the corresponding property (value is an object)
 230     virtual void AddToPropertyCollectionAsObject(int objectID,
 231         const wxClassInfo *classInfo,
 232         const wxPropertyInfo* propertyInfo ,
 233         int valueObjectId) = 0;
 234
 235     // sets the corresponding event handler
 236     virtual void SetConnect(int EventSourceObjectID,
 237         const wxClassInfo *EventSourceClassInfo,
 238         const wxDelegateTypeInfo *delegateInfo ,
 239         const wxClassInfo *EventSinkClassInfo ,
 240         const wxHandlerInfo* handlerInfo ,
 241         int EventSinkObjectID ) = 0;
 242 };
 243
 244 /*
 245 wxRuntimeDepersister implements the callbacks that will depersist
 246 an object into a running memory image, as opposed to writing
 247 C++ initialization code to bring the object to life.
 248 */
 249 class wxRuntimeDepersister : public wxDepersister
 250 {
 251     struct wxRuntimeDepersisterInternal ;
 252     wxRuntimeDepersisterInternal * m_data ;
 253 public :
 254     wxRuntimeDepersister() ;
 255     ~wxRuntimeDepersister() ;
 256
 257     // returns the object having the corresponding ID fully constructed
 258     wxObject *GetObject(int objectID) ;
 259
 260     // allocate the new object on the heap, that object will have the passed in ID
 261     virtual void AllocateObject(int objectID, wxClassInfo *classInfo ,
 262         wxxVariantArray &metadata) ;
 263
 264     // initialize the already allocated object having the ID objectID with the Create method
 265     // creation parameters which are objects are having their Ids passed in objectIDValues
 266     // having objectId <> wxInvalidObjectID
 267
 268     virtual void CreateObject(int objectID,
 269         const wxClassInfo *classInfo,
 270         int paramCount,
 271         wxxVariant *VariantValues ,
 272         int *objectIDValues,
 273         const wxClassInfo **objectClassInfos ,
 274         wxxVariantArray &metadata
 275         ) ;
 276
 277     // destroy the heap-allocated object having the ID objectID, this may be used if an object
 278     // is embedded in another object and set via value semantics, so the intermediate
 279     // object can be destroyed after safely
 280     virtual void DestroyObject(int objectID, wxClassInfo *classInfo) ;
 281
 282     // set the corresponding property
 283     virtual void SetProperty(int objectID,
 284         const wxClassInfo *classInfo,
 285         const wxPropertyInfo* propertyInfo ,
 286         const wxxVariant &variantValue);
 287
 288     // sets the corresponding property (value is an object)
 289     virtual void SetPropertyAsObject(int objectId,
 290         const wxClassInfo *classInfo,
 291         const wxPropertyInfo* propertyInfo ,
 292         int valueObjectId) ;
 293
 294     // adds an element to a property collection
 295     virtual void AddToPropertyCollection( int objectID ,
 296         const wxClassInfo *classInfo,
 297         const wxPropertyInfo* propertyInfo ,
 298         const wxxVariant &VariantValue) ;
 299
 300     // sets the corresponding property (value is an object)
 301     virtual void AddToPropertyCollectionAsObject(int objectID,
 302         const wxClassInfo *classInfo,
 303         const wxPropertyInfo* propertyInfo ,
 304         int valueObjectId) ;
 305
 306     // sets the corresponding event handler
 307     virtual void SetConnect(int eventSourceObjectID,
 308         const wxClassInfo *eventSourceClassInfo,
 309         const wxDelegateTypeInfo *delegateInfo ,
 310         const wxClassInfo *eventSinkClassInfo ,
 311         const wxHandlerInfo* handlerInfo ,
 312         int eventSinkObjectID ) ;
 313 };
 314
 315 /*
 316 wxDepersisterCode implements the callbacks that will depersist
 317 an object into a C++ initialization function.
 318 */
 319
 320 class wxTextOutputStream ;
 321
 322 class wxCodeDepersister : public wxDepersister
 323 {
 324 private :
 325     struct wxCodeDepersisterInternal ;
 326     wxCodeDepersisterInternal * m_data ;
 327     wxTextOutputStream *m_fp;
 328     wxString ValueAsCode( const wxxVariant &param ) ;
 329 public:
 330     wxCodeDepersister(wxTextOutputStream *out) ;
 331     ~wxCodeDepersister() ;
 332
 333     // allocate the new object on the heap, that object will have the passed in ID
 334     virtual void AllocateObject(int objectID, wxClassInfo *classInfo ,
 335         wxxVariantArray &metadata) ;
 336
 337     // initialize the already allocated object having the ID objectID with the Create method
 338     // creation parameters which are objects are having their Ids passed in objectIDValues
 339     // having objectId <> wxInvalidObjectID
 340
 341     virtual void CreateObject(int objectID,
 342         const wxClassInfo *classInfo,
 343         int paramCount,
 344         wxxVariant *variantValues ,
 345         int *objectIDValues,
 346         const wxClassInfo **objectClassInfos ,
 347         wxxVariantArray &metadata
 348         ) ;
 349
 350     // destroy the heap-allocated object having the ID objectID, this may be used if an object
 351     // is embedded in another object and set via value semantics, so the intermediate
 352     // object can be destroyed after safely
 353     virtual void DestroyObject(int objectID, wxClassInfo *classInfo) ;
 354
 355     // set the corresponding property
 356     virtual void SetProperty(int objectID,
 357         const wxClassInfo *classInfo,
 358         const wxPropertyInfo* propertyInfo ,
 359         const wxxVariant &variantValue);
 360
 361     // sets the corresponding property (value is an object)
 362     virtual void SetPropertyAsObject(int objectId,
 363         const wxClassInfo *classInfo,
 364         const wxPropertyInfo* propertyInfo ,
 365         int valueObjectId) ;
 366
 367     // adds an element to a property collection
 368     virtual void AddToPropertyCollection( int objectID ,
 369         const wxClassInfo *classInfo,
 370         const wxPropertyInfo* propertyInfo ,
 371         const wxxVariant &VariantValue) ;
 372
 373     // sets the corresponding property (value is an object)
 374     virtual void AddToPropertyCollectionAsObject(int objectID,
 375         const wxClassInfo *classInfo,
 376         const wxPropertyInfo* propertyInfo ,
 377         int valueObjectId) ;
 378
 379     // sets the corresponding event handler
 380     virtual void SetConnect(int eventSourceObjectID,
 381         const wxClassInfo *eventSourceClassInfo,
 382         const wxDelegateTypeInfo *delegateInfo ,
 383         const wxClassInfo *eventSinkClassInfo ,
 384         const wxHandlerInfo* handlerInfo ,
 385         int eventSinkObjectID ) ;
 386 };
 387
 388 #endif // wxUSE_EXTENDED_RTTI
 389
 390 #endif