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Keivan Norouzi4,513 Points
Why don't we set the member variables right away where we have declared them first?
It is not clear for me that why setting the member variables have to be done inside the onCreate() method and not where we first create them as global variables? I'd appreciate it if someone explain it to me. Thanks
Seth Kroger56,412 Points
From the video, the member variables you're referring to are UI elements of the Activity. Those UI elements won't exist until the call to setContentView() at the start of onCreate(), so the findViewById() method would fail to return anything before them.
Doug Ray7,493 Points
This kind of logic is also true for other types of member variables not necessarily just what you will use in the on create method. For example you may want to declare String mData; but will not receive the actual data until after a certain point :).