Multiple controller cards container
// If the view is A_MultipleViewContainer already, then you don't need to call InstallTo method.
A_MultipleViewContainer *centerView = [A_MultipleViewContainer A_InstallTo:self.view];
[centerView A_AddChild:[DemoLabelViewController createWithNumber:0]];
[centerView A_AddChild:[DemoLabelViewController createWithNumber:1]];
[centerView A_AddChild:[DemoLabelViewController createWithNumber:2]];
[centerView A_AddChild:[DemoLabelViewController createWithNumber:3]];
[centerView A_Display];