Best practise to refreshing adapter data with custom view

Question

I have the following custom view: |--------------------| | [ ] TextView | |--------------------|

This is just a simple CheckBox and a TextView. This View is shown multiple times (days in month), presented on the screen via a list (RecylverView).

For that I have a Fragment which will first read data from a database and then put this data into the list.

String[] data = getDataFromDB();
mRecycler.setAdapter(new MyAdapter(data));

Imagine that every other item has a checked CheckBox. So we have (for example with 4 Items) a list like this: |--------------------| | [ ] TextView | |--------------------| |--------------------| | [X] TextView | |--------------------| |--------------------| | [ ] TextView | |--------------------| |--------------------| | [X] TextView | |--------------------|

The user can now check or uncheck the CheckBox (well, it is a checkbox :)). On programmer side the dataArray from the database must be updated too. Because, if I don't do so and the user scroll, the specific list-item should be created with the old data. Yeah, that is the recycler thing is for :)

Anyway. When the user check/uncheck I need to updated the data. And here is my question: What is the best practice to do so?

One idea is to set an Interface in the adapter for each View, to be notified when something changes. Each CheckBox becomes a listener which will be called when the user clicks on a CheckBox. The listener received a notification (from the adapter) and it can update the data.

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {

    @Override
    public void onBindViewHolder(MyViewHolder myViewHolder, int position) {
        myViewHolder.myView.setModel(data.get(position));
        myViewHolder.myCheckBox.setOnCheckedChangeListener(new OnChanged) {
            // TODO: Update data and refresh list/adapter
        }
    }

}

Another idea is to put the list and the data in a custom View. The custom View implements the CheckedChanceListener and updates the database and list Adapter.

public class TimeTrackingCardView extends CardView {

    public void setListThings(String[] data, MyAdapter adapter) {
        myCheckBox.setOnCheckedChangeListener(new OnChanged) {
            // TODO: Update data and refresh list/adapter
        }
    }

}

Both ideas aren't very good. Any other ideas or patterns for refreshing Adapter data using custom Views?

Note: This is a very basic custom View. My app actually has multiple Views (4 Buttons with text changes, 1 CheckBox and a EditText) but with the same idea.

You say the ideas aren't very good. Can you please explain it why? — Blehi, Sep 08 '15 at 07:34

score 0 · Answer 1 · edited May 23 '17 at 12:22

0

Have a look at Why doesn't RecyclerView have onItemClickListener()? And how RecyclerView is different from Listview?. The OnClick Probelm is very similar to your Problem. This post helped me a lot.

edited May 23 '17 at 12:22

Community

1
1

answered Sep 07 '15 at 06:43

Bernd

928
10
8

I don't believe this addresses the issue. The question is about the best way to manage the data that backs the `Adapter` upon `CheckBox` changes. – Paul Burke Sep 07 '15 at 13:46
Yes, that is'n exactly the answer I've looked for. But that helps a little bit. – StefMa Sep 07 '15 at 17:56

Best practise to refreshing adapter data with custom view

1 Answers1