This is not working with fragments. about blog-android-clean-coding-approach

[suvansh-dev]

yes thanks it worked.

[suvansh-dev]

Thanks but it worked without adding a listener in ViewHolder as i said.

[grasmussen-phunware]

Hi @suvansh-dev 👋 ,

It is hard to tell with only having the one fragment class pasted here to see what issue might exist.

With the provided issue, I would not call this an open issue with the code in this repo, as it has been modified separately and it could be another issue.

Do you have a fork of this repo, with your commits, and that you could reference here in this conversation? Providing that public fork information would allow for me to look at the implementation to see where I can help.

Are there any binding errors printed out to LogCat?

With MVVM, where the View component can also include Activities and Fragments, whether the code is in an Activity or Fragment, it really does not matter.

Could double check through the implementation to see if anything else was changed?

Best,

Gregory

[suvansh-dev]

Hi @grasmussen-phunware ,
Here is the forked project https://github.com/suvansh-dev/blog-android-clean-coding-approach , I have set the recycler view background to black to check whether recycler view is visible or not and the background turned out to be black of the fragment but still the items are not visible plus there is no error which i am receiving in the logcat, its like the problem is with the setup()

[suvansh-dev]

@grasmussen-phunware This worked by this way:

FragmentBlankBinding binding = DataBindingUtil.inflate(inflater, R.layout.fragment_blank, container, false);

       RecyclerView recyclerView = binding.getRoot().findViewById(R.id.data_recycler_view);
       recyclerView.setLayoutManager(new LinearLayoutManager(recyclerView.getContext()));
       recyclerView.addItemDecoration(new DividerItemDecoration(recyclerView.getContext(), VERTICAL));

       dataViewModel = new DataViewModel();
       binding.setViewModel(dataViewModel);

       binding.executePendingBindings();
      
       recyclerView.setAdapter(dataViewModel.getAdapter());
       dataViewModel.setUp();
       
       return binding.getRoot();

But i don't know the reason why this need to be done and why the above code is working in activity but not in fragment.

[grasmussen-phunware]

Hi @suvansh-dev,

I see the issue with the original code, which creates a MyFragmentViewModel object twice and doesn't reuse the object reference. The class level scoped object reference, dataViewModel, should be set to a new instance of MyFragmentViewModel in method onCreate. Then, in method onViewCreated, the object instance should not be set again. It should be reused.

This will get you back on track.

I've attached a screenshot of the fragment in a working state from the forked repo as well as a screenshot of the project running with those changes on a Pixel 2 this morning.

Best,

Gregory

I'm closing this issue, as it's not an issue with the project and the guidance will get the developer back on track.

[grasmussen-phunware]

You're welcome @suvansh-dev .

[suvansh-dev]

Hi, Where can we attach a click listener for RecyclerView items(for textview) as you have specified setUp(..) method for adding listeners but what we actually do is specifying up a method name in onClick attribute of xml and then use that method in the ViewModel class. So how does setUp(...) is useful in this case?

[grasmussen-phunware]

Hi @suvansh-dev,

With future questions, please open up a new issue and label it with the question label. Doing so will help keep issues relevant as well as helping others to better find what they are looking for when searching the issues.

When approaching making an MVVM implementation your own or creating your own, I recommend looking at it in terms of:

1. the functional requirements
2. how changes/additions adhere to the project's architecture (MVVM)
3. keeping in mind best practices, programming principles, and more

To answer your question, you don't need to use method setUp(). It's just a possibility for listeners in general. One could simply add a click listener in a ViewHolder, and the click listener would then call a function on the corresponding ViewModel. Doing this does follow the MVVM Architecture pattern, where views can call on viewmodel's functions, which essentially provide commands for the View.

Best,

Gregory