How styles in ui binder gets reflected in deployed application

Question

I have seen some stylesheets are injected in hosted html page which has href value null. Are those coming from styles declared in ui.xml file? How the styles declared in ui.xml files get reflected in gwt?

Answer 1

<ui:style> in UiBinder are internally known as implicit CssResource: <ui:style>, <ui:image> and <ui:data> generate implicit resources in an implicit ClientBundle. UiBinder automatically calls ensureInjected() on the implicit CssResources (generated by <ui:style>)