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Start your free trialKeivan Norouzi
4,513 PointsWhy 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
2 Answers
Seth Kroger
56,413 PointsFrom 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 Ray
7,493 PointsThis 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 :).
Keivan Norouzi
4,513 PointsGood point, Thanks a lot :)
Keivan Norouzi
4,513 PointsKeivan Norouzi
4,513 PointsThank you so much. It helped a lot :)