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Android

Posted by dlpuxdzztg
dlpuxdzztg
8,243 Points

Having Trouble Adding Items to My Array

Hello.

So the scenario is I have a list of ListItem items that I'm displaying through a RecyclerView, I wan't them to be displayed as checkbox items (the only parameter they have is the parameter for the text of the checkbox.) When I try to add the item to the list however, I get an error:

AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                View view = getLayoutInflater().inflate(R.layout.dialog_fragment_layout, null);

                mConfirmTextView = (TextView) view.findViewById(R.id.confirmTextView);
                mCancelTextView = (TextView) view.findViewById(R.id.cancelTextView);
                mAssignmentEditText = (EditText) view.findViewById(R.id.assignmentEditText);

                builder.setView(view);
                final AlertDialog dialog = builder.create();
                dialog.show();

                mCancelTextView.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        dialog.dismiss();
                    }
                });

                mConfirmTextView.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        String item;
                        item = mAssignmentEditText.getText().toString();
                        mItems.add(item); //The error is here
                    }
                });

Here is the code for my ListAdapter:

public class ListAdapter extends RecyclerView.Adapter<ListAdapter.ViewHolder> {

    private ArrayList<ListItem> mList;
    private Context mContext;

    public ListAdapter(Context context, ArrayList<ListItem> items) {
        mContext = context;
        mList = items;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.list_item_main, parent, false);
        ViewHolder viewHolder = new ViewHolder(view);
        return viewHolder;
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        holder.bindHolder(mList.get(position));
    }

    @Override
    public int getItemCount() {
        return mList.size();
    }

    public class ViewHolder extends RecyclerView.ViewHolder {

        public CheckBox mCheckBox;

        public ViewHolder(View itemView) {
            super(itemView);

            mCheckBox = (CheckBox) itemView.findViewById(R.id.checkBox);
        }

        public void bindHolder(ListItem item) {
            mCheckBox.setText(item.getAssignment());
        }
    }
}

Thank you!

1 Answer

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

You're adding a String to the list in the dialog handler but your adapter has a list of ListItems, which I assume is a custom model class of yours. You have a type mismatch as a result. You need to create a new ListItem from your string to add.

dlpuxdzztg
dlpuxdzztg
8,243 Points

I'm a little lost, what do you mean by 'create a new ListItem from your string to add'?

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

I'm assuming your ListItem has a constructor with a String argument for "assignment". or you can use the default constructor and use setAssignment()

dlpuxdzztg
dlpuxdzztg
8,243 Points

It does have an empty constructor:

public class ListItem implements Parcelable {
    private String mAssignment;

    public ListItem() {}

    public String getAssignment() {
        return mAssignment;
    }

    public void setAssignment(String assignment) {
        mAssignment = assignment;
    }

    @Override
    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel dest, int flags) {
        dest.writeString(mAssignment);
    }

    protected ListItem(Parcel in) {
        mAssignment = in.readString();
    }

    public static final Creator<ListItem> CREATOR = new Creator<ListItem>() {
        @Override
        public ListItem createFromParcel(Parcel source) {
            return new ListItem(source);
        }

        @Override
        public ListItem[] newArray(int size) {
            return new ListItem[size];
        }
    };
}

But in order to use setAssignment(), I need to create a ListItem object in my MainActivity. Should I do just that?