How to assign custom theme of Fiori Launchpad on EP to custom UI5 iview content ?

Hi All,

We created a custom theme by Theme Designer at  EP(based on SAP NetWeaver 7.5 SP1)  and assigned it to Fiori Launchpad. The result is below .

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and we added some custom sapui5 iviews inside the EP . When we navigate to them , custom ui5 apps are using their own themes  as expected .

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so my question is how I can assign the custom theme of Portal to Custom UI5 app ?

Thanks .