How to compare Any type arraylist `var getVideoLis...

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[bhavin]

How to compare Any type arraylist
var getVideoList: ArrayList<Any> look at this my code https://paste.ofcode.org/PpCQuDjkAvtKpv7U29k7cD

[diesieben07]

I am not sure what your question is. I am guessing ActionHelp does not implement equals and hashCode, which means contains and friends will use object identity. You should either implement equals and hashCode or make it a data class, which will generate those for you based on the component values.

[bhavin]

@diesieben07 this is my ActionHelp class https://paste.ofcode.org/38JtXHaKMdDD3MFrrmfP6Xz
I don't understand by implement equals

[gildor]

also runnable code snippet is very helpful for anyone who wants to help you

[gildor]

https://play.kotlinlang.org

[diesieben07]

@bhavin Please actually clarify what your issue is.

[bhavin]

ok I have an ArrayList with data which I get from another activity so I want to add new data in same list so problem is I have already some data with same id and I don't want to add same data in arraylist . I can do that If I add type in arraylist like var getVideoList: ArrayList<ActionHelp> but instead I'm using (i need to use ) var getVideoList: ArrayList<Any> so I can't compare this list with ActionHelp class's data.

[diesieben07]

The generic type you specify doesn't matter, ArrayList<ActionHelp> and ArrayList<Any> will behave exactly the same in regards to equality of their items.
To me it sounds like you want a Map<ID, ActionHelp>

[bhavin]

I checked this https://stackoverflow.com/a/30022564/6333971 It's exactly like you said before @diesieben07 but I can't understand It😅 I am trying that right now

[bhavin]

hello guys @diesieben07 @gildor I don't know how to do using Map<ID, ActionHelp> but I did Like this which is working right now

ActionHelp Class : https://paste.ofcode.org/H8rg7Ly9vrTMVU4JXujcAc

Small code snippet : https://paste.ofcode.org/BUB9ij6YzWMmJ5aB4kZQ7F

please check It and suggest me better way 🙂

[diesieben07]

@bhavin I am really not sure what you are trying to achieve there. Your equals method will not do anything useful. It classifies everything that is not the same object as "equal". Moreover, if you override equals you must override hashCode in coordination, the two methods always go together.

[bhavin]

@diesieben07 What I'm trying to achieve is if Item is already in list than don't want to add it into list again

[diesieben07]

Yes. You can either implement equals and hashCode accordingly (so that the same item is regarded as equal) or you can use a Map if you don't want to do that.

[bhavin]

Yeah I get It but don't know how? that's problem😅 Thanks

[diesieben07]

equals needs to return true if you want the two objects (this and the parameter) to be equal.

[bhavin]

@diesieben07 You are saying to do like this https://dzone.com/articles/working-with-hashcode-and-equals-in-java Right?

[diesieben07]

Yes. Kotlin can do all that for you automatically if you use a data class

[bhavin]

yeah I read that but problem is I'm not using List < Student > studentsLst = new ArrayList < Student > (); I m use like this List < Any > studentsLst = new ArrayList < Any > (); so problem is when I try to do studentsLst.contain is not working

[diesieben07]

It is completely irrelevant whether you use List<Any> or List<Student>

[diesieben07]

equals and hashCode are virtual (non-static) methods, they will be dispatched at runtime.

[bhavin]

@diesieben07 Thanks and I did it using equals It's very simple and I wasted 2 hours .. sorry for waste your time and I'm thinking some time "kabhi kabhi to esa lagta he apun hi bhagvan hu" feel like dumb😅