How can viewport shading functionality be used to preview render result in Blender 2.80? I could make a glass cube in Blender 2.79b in Cycles Render. Also, I could use the Viewport Shading feature in Blender 2.79b to see my desired result. 

But in Blender 2.8, it didn't seem to do anything like that. When I tried the same process in creating a simple glass cube in 2.8, it didn't seem to have the desired result. I mean, I tried using 2.8's Viewport Shading part and set it to Cycles in 2.8, but it doesn't seem to do anything. 

2.8 is a little new to me. Does anyone understand my situation here? If so, how did you guys overcome this?

I just feel like 2.8 is not well-developed yet and that I should probably use 2.79b at this moment for now.
Switch to Cycles, Add a glass shader, press Z and set the viewport to rendered: