java - Can I create a single class which can be the parent for every type of Activity? -

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i wish have single class of activity classes extend. have listactivities, activities, mapactivities, tabactivities, etc in app.

i have many of these different activities in app, ~12 activities. want each of them have methods in parent class.

right now, have created 4 parent activity classes extended activity depending on type(listactivity, activity, mapactivity, tabactivity)

i creating lot of redundant code - each of 4 parent activities has identical code, in exception class activity extends.

here example may clarify problem is:

  • i have activity: menuscreen extends baselistactivity
  • baselistactivity extends listactivity

  • baselistactivity contains methods , fields want activities have access to

  • i have activity: homescreen extends baseactivity

  • baseactivity extends activity
  • baseactivity contains same methods , fields in other base[<type>]activity classes(such baselistactivity)

these methods/fields copy-pasted base[<type>]activity, , seems awfully redundant me.

can create master activity class types of activity classes can use parent? if not, stuck copy , pasting code , feeling gross/dirty it?

can create master activity class types of activity classes can use parent?

no, sorry.

if not, stuck copy , pasting code , feeling gross/dirty it?

first, not need listactivity or tabactivity. not need listactivity listview; not need tabactivity tabhost. knocks things down 2 base classes: activity , mapactivity. unfortunately, do need extend mapactivity use mapview.

for that, can use composition minimize redundancy. rather "methods , fields want activities have access to" being implemented on activity, implement them on other object, , have baseactivity , basemapactivity hold onto instance of object. still need amount of duplicate code (e.g., lifecycle methods onstop()), more stuff can located in single class.


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