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96 lines
2.5 KiB
Plaintext
96 lines
2.5 KiB
Plaintext
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/**
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* \class QgsMapLayerRegistry
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* \brief This class tracks map layers that are currently loaded an provides
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* a means to fetch a pointer to a map layer and delete it
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*/
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class QgsMapLayerRegistry : QObject
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{
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%TypeHeaderCode
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#include <qgsmaplayerregistry.h>
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%End
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public:
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//! Returns the instance pointer, creating the object on the first call
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static QgsMapLayerRegistry * instance();
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//! Return the number of registered layers.
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int count();
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~QgsMapLayerRegistry();
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//! Retrieve a pointer to a loaded plugin by id
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QgsMapLayer * mapLayer(QString theLayerId);
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//! Retrieve the mapLayers collection (mainly intended for use by projectio)
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QMap<QString,QgsMapLayer*> & mapLayers();
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/** Add a layer to the map of loaded layers
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@returns NULL if unable to add layer, otherwise pointer to newly added layer
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@note
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As a side-effect QgsProject is made dirty.
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Emits signal that layer has been added only if theEmitSignal is true (by default).
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Not emitting signal is useful when you want to use registry also for layers
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which won't be used in main map canvas but will be used in a special one
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*/
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QgsMapLayer * addMapLayer(QgsMapLayer * theMapLayer /Transfer/, bool theEmitSignal = TRUE);
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/** Remove a layer from qgis
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@note
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As a side-effect QgsProject is made dirty.
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Any canvases using that layer will need to remove it
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theEmitSignal - see addMapLayer()
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*/
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void removeMapLayer(QString theLayerId, bool theEmitSignal = TRUE);
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/** Remove all registered layers
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@note raises removedAll()
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As a side-effect QgsProject is made dirty.
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*/
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void removeAllMapLayers();
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signals:
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/** emitted when a layer is removed from the registry
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connected to main map canvas and overview map canvas remove()
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*/
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void layerWillBeRemoved(QString theLayerId);
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/** emitted when a layer is added to the registry
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connected to main map canvas and overview map canvas addLayer()
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*/
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void layerWasAdded(QgsMapLayer * theMapLayer);
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/** emitted when ALL layers are removed at once
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This could have been implemented by iteratively signalling
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layerWillBeRemoved() for each layer as it is removed. However, this
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generally causes a cascade of effects that are unnecessary if we're
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ultimately removing all layers. E.g., removing the legend item
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corresponding to the layer. Why bother doing that when you're just going
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to clear everything anyway?
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*/
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void removedAll();
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protected:
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//! protected constructor
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QgsMapLayerRegistry( QObject * parent = 0 );
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}; // class QgsMapLayerRegistry
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