如何从 RecyclerView 适配器（Kotlin）评估片段中的变量（更改值）以进行条件处理？

Question

I'm new to all of this and was making good progress but I have hit a brick wall with working out how to do the next thing. I am using Kotlin and have a Fragment with an associated Recyclerview Adapter. I would like to set OnClick (On or Off) against items in a row depending upon a value in the Fragment which could change at any time.

My adapter works fine to show and update the array of data and also to implement OnClick.

I have tried sending a data element via a constructor which changed in the fragment but always showed as the initial setting in the adapter. The same with trying to call a method.

Many other questions touch on the issue but only show snippets of code, and it seems that I'm not advanced enough to get them working successfully in my code.

Could anyone please provide a pointer to a working set of Kotlin code that includes parsing a variable from fragment to adapter - perhaps in Git or a tutorial. I'm sure that if I can study a working program I can move forward. Thank you.

Answer 1

It would have been better if you had included your Adapter and Fragment code in the question, that would have helped us in understanding how you have setup everything and what data model are you passing to adapter.

But looking at your question, one solution that comes to my mind is to add an enabled boolean in your data model that is displayed in the ViewHolder. Using this you can set view.clickable = model.enabled . Now whenever your "value in the Fragment" changes you can update this list and let the adapter rebind items.

Note that the above solution is when you want to selectively enable/disable clicks on individual items. If you want to do this for all items at once, it's better to create a variable in adapter that you can change from the Fragment, and inside the clickListener you can check the value of that adapter variable. If it's false, just return out of the click listener. Something like,

view.setOnClickListener {
    if(adapterValue) {
        // handle Click
    }
}

If this approach doesn't help, I would ask you to add more context in your question and show what you have done so far.