LEADTOOLS Vector C++ Class Library Help > Classes and Member Functions > LVectorLayer > LVectorLayer Class Members > LVectorLayer::LVectorLayer |
#include "ltwrappr.h"
LVectorLayer::LVectorLayer(pLayer, pVector=NULL)
LVectorLayer::LVectorLayer(pVector)
LVectorLayer::LVectorLayer(pLayerDesc=NULL, pVector=NULL)
pVECTORLAYER pLayer; |
/* pointer to a VECTORLAYER structure */ |
LVectorBase * pVector; |
/* pointer to an LVectorBase object */ |
pVECTORLAYERDESC pLayer; |
/* pointer to a VECTORLAYER structure */ |
Constructs and initializes the different member variables of the LVectorLayer object.
Parameter |
Description |
pLayer |
Pointer to a VECTORLAYER structure that contains information used to create and initialize the new vector layer. |
pVector |
Pointer to an LVectorBase object. The newly created vector layer will be associated with this LVectorBase object. |
pLayerDesc |
Pointer to a VECTORLAYERDESC structure that contains information used to create and initialize the new vector layer. |
Returns
None
Comments
LVectorLayer::LVectorLayer(pLayer, pVector=NULL) is a constructor for the LVectorLayer object. It takes a valid pVECTORLAYER pointer and creates an LVectorLayer object. This constructor should mainly be used with the LVectorBase::EnumLayers function, which returns a valid pVECTORLAYER pointer in its LVectorBase::EnumLayersCallBack member function.
LVectorLayer::LVectorLayer(pVector) creates a valid LVectorLayer object that is associated with the specified LVectorBase object.
LVectorLayer::LVectorLayer(pLayerDesc=NULL, pVector=NULL) creates an LVectorLayer object based on the information provided in pLayerDesc and associates the newly created LVectorLayer object with the specified LVectorBase object.
To use the LVectorLayer::LVectorLayer(pLayerDesc=NULL, pVector=NULL) constructor, optionally declare a variable of type VECTORLAYERDESC, fill the structure and pass its address to this constructor. To associate the newly created vector layer with an LVectorBase object, pass a valid pointer to an LVectorBase object as the second parameter. If the second parameter is NULL, then the LVectorLayer object is not yet associated with an LVectorBase object. The following functions automatically associate an LVectorLayer object with an LVectorBase object: LVectorBase::AddLayer, LVectorBase::GetLayerByName, LVectorBase::GetLayerByIndex, LVectorBase::SetActiveLayer, and LVectorBase::GetActiveLayer. The LVectorLayer::SetVector also associates an LVectorLayer object with an LVectorBase object.
Required DLLs and Libraries
LVKRN For a listing of the exact DLLs and Libraries needed, based on the toolkit version, refer to Files To Be Included With Your Application. |
See Also
Example
This is an example for LVectorLayer::LVectorLayer(pVector):
// This example enumerates through all layers in a vector. #ifdef LMyVectorBase4 class LMyVectorBase4: public LVectorBase { public: L_INT m_nLayerCount ; public: LMyVectorBase4() {m_nLayerCount=0;}; virtual ~LMyVectorBase4(){}; virtual L_INT EnumLayersCallBack(pVECTORHANDLE pVector, pVECTORLAYER pLayer); }; #endif // #ifdef LMyVectorBase4 L_INT LVectorLayer__LVectorLayerExample_1(HWND hWnd, LMyVectorBase4 *pMyVector) { UNREFERENCED_PARAMETER(hWnd); L_INT nRet; LMyVectorBase4 MyVector; L_TCHAR szMsg[100]; pMyVector->m_nLayerCount=0; nRet = pMyVector->EnumLayers(); if(nRet != SUCCESS) return nRet; wsprintf(szMsg, TEXT("Total Layers[%d]"), pMyVector->m_nLayerCount); MessageBox(NULL, szMsg, TEXT(""), MB_OK); return SUCCESS; } // This is an example for LVectorLayer::LVectorLayer(pVector): //Example95 L_INT LVectorLayer__LVectorLayerExample_2(HWND hWnd, LVectorBase *pVector) { UNREFERENCED_PARAMETER(hWnd); LVectorLayer VectorLayer(pVector); //Assoicate the LVectorLayer with an LVectorBase //Note that most functions that use an LVectorLayer do this automatically VectorLayer.SetVector(pVector); //...Do something with the vector layer //...LVectorLayer destructor is called when VectorLayer goes out of scope. return SUCCESS; } // This is an example for LVectorLayer::LVectorLayer(pLayerDesc=NULL, pVector=NULL): // This example will add a new layer to a vector handle. L_INT LVectorLayer__LVectorLayerExample_3(HWND hWnd, LVectorBase *pVector) { UNREFERENCED_PARAMETER(hWnd); L_INT nRet; LVectorLayer VectorLayer; VECTORLAYERDESC LayerDesc; nRet = VectorLayer.GetLayerDesc(&LayerDesc); if(nRet != SUCCESS) return nRet; lstrcpy(LayerDesc.szName, TEXT("Terry's New Layer")); nRet = VectorLayer.SetLayerDesc(&LayerDesc); if(nRet != SUCCESS) return nRet; nRet = pVector->AddLayer(&VectorLayer, VECTOR_FLAGS_RENAME_DUPLICATES); if(nRet != SUCCESS) { MessageBox( NULL, TEXT("Could not add layer!"), TEXT(""), MB_OK ); return nRet; } //...LVectorLayer destructor is called when VectorLayer goes out of scope. return SUCCESS; } // This is also an example for LVectorLayer::LVectorLayer(pLayerDesc=NULL, pVector=NULL): // This example demonstrates the use of the LVectorLayer constructor L_INT LVectorLayer__LVectorLayerExample_4(HWND hWnd, LVectorBase *pVector) { UNREFERENCED_PARAMETER(hWnd); L_INT nRet; VECTORLAYERDESC LayerDesc; LayerDesc.bLocked = FALSE; LayerDesc.bVisible = TRUE; LayerDesc.dwTag = 1; LayerDesc.nSize = sizeof(VECTORLAYERDESC); lstrcpy(LayerDesc.szName, TEXT("My New Layer")); LVectorLayer VectorLayer(&LayerDesc); nRet = pVector->AddLayer (&VectorLayer, VECTOR_FLAGS_RENAME_DUPLICATES); if(nRet != SUCCESS) { MessageBox( NULL, TEXT("Could not add layer!"), TEXT(""), MB_OK ); return nRet; } //...LVectorLayer destructor is called when VectorLayer goes out of scope. return SUCCESS; }