Android ViewGroup to ViewHolder

Question

I am building a simple Todolist-Android App using Retrofit2. I got an Adapter-Class to build up a Recyclerview with the Todos of a list. This works without problems (here goes the code):

public class TodolistAdapter extends RecyclerView.Adapter<TodolistAdapter.TodoViewHolder> {
private ArrayList<Todolist> todoData;

public static class TodoViewHolder extends RecyclerView.ViewHolder {

    public TextView todoView;

    public TodoViewHolder(TextView textView) {
        super(textView);
        todoView = textView;
    }
}
    public TodolistAdapter(ArrayList<Todolist> dataset) {
        todoData = dataset;
    }
    @Override
    public TodolistAdapter.TodoViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        // create a new view
        TextView v = (TextView) LayoutInflater.from(parent.getContext())
                .inflate(R.layout.todolist_text_view, parent, false);

        TodoViewHolder vh = new TodoViewHolder(v);
        return vh;
    }

// Replace the contents of a view (invoked by the layout manager)
@Override
public void onBindViewHolder(final TodoViewHolder holder, final int position) {
    // - get element from your dataset at this position
    // - replace the contents of the view with that element
    holder.todoView.setText(todoData.get(position).getList_name());
    holder.todoView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            String listID = todoData.get(position).getList_id();
            Intent intent = new Intent(holder.todoView.getContext(), TodoActivity.class);
            intent.putExtra("list_id", listID);
            holder.todoView.getContext().startActivity(intent);
        }
    });
}

// Return the size of your dataset (invoked by the layout manager)
@Override
public int getItemCount() {
    return todoData.size();
}

}

What I get is a List with the Todos as TextViews. Now I want to add a Checkbox at the left of the TextViews to check/uncheck a single todo.

But I don't know how to hand over the TextView and the Checkbox to the ViewHolder. Do I have to create a Viewgroup inside the corresponding xml and hand it over in the ViewHolder's constructor? How could a possible xml look like? I'm a bit stuck over here because I'm new to the Android View world.

Answer 1

For adding CheckBox to left of textview you have to add checkbox in your R.layout.todolist_text_view layout & initialize it as same as you initialize textview.

Below code for checkbox :

<android.support.v7.widget.AppCompatCheckBox
            android:id="@+id/chkboxId"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/some_text"
            />

Answer 2

You need markup, for example, with Constraint Layout, which will include both TextView and CheckBox.

Answer 3

You need to change the todolist_text_view.xml layout to as include a checkbox.

Then change the onCreateViewHolder as follows:-

 @Override
public TodolistAdapter.TodoViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    // create a new view
    View v = LayoutInflater.from(parent.getContext())
            .inflate(R.layout.todolist_text_view, parent, false);

    TodoViewHolder vh = new TodoViewHolder(v);
    return vh;
}

Now change the TodoViewHolderas below :-

public static class TodoViewHolder extends RecyclerView.ViewHolder {

public TextView todoView;
public Checkbox checkbox;

public TodoViewHolder(View view) {
    super(textView);
     todoView = view.findViewById(R.id.textViewId);
     checkbox = view.findViewById(R.id.checkboxId);        
}
}

Refer this for complete understanding on how these methods work together.

Create List with RecyclerView