Translucent Activity filling the entire screen

Question

I\'d like to have an activity (2) with translucent aspect over another activity (1), aligned at the top of the screen (4).

Answer 1

Finally, this theme worked to get a result like image number 4:

In my activity 2 layout, I could eihter set android:background="@android:color/transparent" or not set any value at all to make it work.

Thanks to MikeIsrael and Veer for their help.