为开发人员准备的文档,涵盖QGIS的多种功能实现和代码。

Similarlytovectorlayers,rasterlayerscanbeloadedusingtheaddRasterLayerfunctionoftheQgisInterface:

Thiscreatesanewlayerandaddsittothemaplayerregistry(makingitappearinthelayerlist)inonestep.

RasterlayerscanalsobecreatedfromaWCSservice.

detailedURIsettingscanbefoundinproviderdocumentation

AlternativelyyoucanloadarasterlayerfromWMSserver.Howevercurrentlyit’snotpossibletoaccessGetCa-

pabilitiesresponsefromAPI—youhaveto

knowwhatlayersyouwant

3.3MapLayerRegistry

Ifyouwouldliketousetheopenedlayersforrendering,donotforgettoaddthemtomaplayerregistry.Themap

layerregistrytakesownershipoflayersandtheycanbelateraccessedfromanypartoftheapplicationby

their

uniqueID.Whenthelayerisremovedfrommaplayerregistry,itgetsdeleted,too.

Addingalayertotheregistry

Layersaredestroyedautomaticallyonexit,howeverifyouwanttodeletethelayer

explicitly,use

Foralistofloadedlayersandlayerids,use

TODO:Moreaboutmaplayerregistry?