# Item View {#item-view} An Item view is a scrollable container that contains several items. It can have several layouts. There are a few built-in layouts that the application writer can use: |GRID |SPIRAL |DEPTH | |:----------------------:|:------------------------:|:-----------------------:| |||| The application writer can also create their own custom layout by inheriting from Dali::Toolkit::ItemLayout. ## Item Factory To create an item-view, the application writer has to provide an item-factory. An ItemFactory provides methods to create items and how many items there are among other things. ~~~{.cpp} class MyFactory : public Dali::Toolkit::ItemFactory { public: virtual unsigned int GetNumberOfItems() { // Should return the number of items return MY_ITEM_COUNT; } virtual Actor NewItem( unsigned int itemId ) { // We should create the actor here that represents our item based on the itemId given. // Here we'll create an ImageActor which uses the the itemId to parse the image in a particular directory. std::ostringstream imageName; imageName << "my-image-folder/" << itemId << ".png"; // If item was 10, then this would result in my-image-folder/10.png Dali::ResourceImage image = Dali::ResourceImage::New( imageName.str() ); // Create an Image Actor from the image and return return Dali::ImageActor::New( image ); } }; ~~~ These overridden methods in our factory will be called by the Item View. ## Creating an ItemView ~~~{.cpp} MyFactory factory; // Should store this as a member variable Dali::Toolkit::ItemView itemView = Dali::Toolkit::ItemView::New( factory ); // Pass in our factory itemView.SetParentOrigin( ParentOrigin::CENTER ); itemView.SetAnchorPoint( AnchorPoint::CENTER ); // Now create a layout Dali::Toolkit::ItemLayoutPtr spiralLayout = Dali::Toolkit::DefaultItemLayout::New( Dali::Toolkit::DefaultItemLayout::SPIRAL ); // ... and add the layout to the item view itemView.AddLayout( spiralLayout ); // More layouts can be created and added to the item-view // Activate the layout itemView.ActivateLayout( 0, // The layout ID matches the order in which layouts are added Dali::Stage::GetCurrent().GetSize(), // Use the stage's size as our item-view size 0 ); // We want the item-view to appear straight away // And add to the stage Dali::Stage::GetCurrent().Add( itemView ); ~~~ */