如何选中单选按钮以及如何仅控制在列表视图中选择的一个单选按钮

Question

I trying to add my data to a list view. I am using adapter on this. Inside the list view have radio button and some field.

class StocktakeEditViewAdaptor : BaseAdapter<Model.FileRecord>
{
private Dictionary<int, bool> checkDictionary = new Dictionary<int, bool>();



public override View GetView(int position, View convertView, ViewGroup parent)
    {
        var item = items[position];
        View view = convertView;

        //if (view == null)
        {
            view = context.LayoutInflater.Inflate(Resource.Layout.StockTakeEditDetailList, null);
            view.DuplicateParentStateEnabled = true;


            createdview.Add(view);
            RadioButton lblradio = view.FindViewById<RadioButton>(Resource.Id.lblradio);
            lblradio.Tag = item.FileRecord_ID + ":" + item.ST_filename + ":" + item.ST_BinLoc;
lblradio.Checked = checkDictionary[position];   //add position here
            lblradio.SetOnCheckedChangeListener(null);
            lblradio.SetOnCheckedChangeListener(new CheckedChangeListener(this.context));

            view.FindViewById<TextView>(Resource.Id.txtLineNo).Text = item.FileRecord_ID.ToString();  //my field in adapter.
            view.FindViewById<TextView>(Resource.Id.txtbinloc).Text = item.ST_BinLoc.ToString();
            view.FindViewById<TextView>(Resource.Id.txtBarcodett).Text = item.ST_Barcode.ToString();
            view.FindViewById<TextView>(Resource.Id.txtQtytt).Text = item.ST_Qty.ToString();


            if (!view.HasOnClickListeners)
                view.Click += View_LongClick;
            view.RefreshDrawableState();
        }
        return view;
    }

        public void OnCheckedChanged(CompoundButton buttonView, bool isChecked)
        {
            for (int i = 0; i < checkDictionary.Count(); i++)
            {
                if (i == (int)buttonView.Tag)
                {
                    checkDictionary[i] = true;   //error on here
                }
                else
                {
                    checkDictionary[i] = false;  //error on here
                }
            }

        }

I able to show my record in list view.But the radio button can select multiple. I do not want select multiple record.

Answer 1

You could create a collection to store the check status of the radiobutton, and then load the collection when it is loaded in getView . like this :

class YourAdapter : BaseAdapter,CompoundButton.IOnCheckedChangeListener
    {
        private Dictionary<int, bool> checkDictionary = new Dictionary<int, bool>();
        int[] item;  //raplace your own data
        public MyAdapter(int[] value) //raplace your own data
        {
            item = value;
            for (int i = 0; i < item.Length; i++)
            {
                checkDictionary.Add(i,false);
            }
        }



public override View GetView(int position, View convertView, ViewGroup parent)
    {
       var item = items[position];
       View view = convertView;

    //if (view == null)
      {
        view = context.LayoutInflater.Inflate(Resource.Layout.StockTakeEditDetailList, null);
        view.DuplicateParentStateEnabled = true;


        createdview.Add(view);
        RadioButton lblradio = view.FindViewById<RadioButton>(Resource.Id.lblradio);

        lblradio.Tag = position;
        lblradio.Checked = checkDictionary[position];
        lblradio.SetOnCheckedChangeListener(this);

        view.FindViewById<TextView>(Resource.Id.txtLineNo).Text = item.FileRecord_ID.ToString();  //my field in adapter.
        view.FindViewById<TextView>(Resource.Id.txtbinloc).Text = item.ST_BinLoc.ToString();
        view.FindViewById<TextView>(Resource.Id.txtBarcodett).Text = item.ST_Barcode.ToString();
        view.FindViewById<TextView>(Resource.Id.txtQtytt).Text = item.ST_Qty.ToString();


        if (!view.HasOnClickListeners)
            view.Click += View_LongClick;
        view.RefreshDrawableState();
      }
        return view;
    }
public void OnCheckedChanged(CompoundButton buttonView, bool isChecked)
    {
        for (int i = 0; i < checkDictionary.Count; i++)
         {
           if (i == (int) buttonView.Tag)
            {
                checkDictionary[i] = true;
            }
           else
            {
                checkDictionary[i] = false;
            }
         }
            NotifyDataSetChanged();

      }
   }

Answer 2

The reason you can select multiple radio button is that they do not belong to the same Radio button group.

A quote from the official document of Android Radiobutton .

To create each radio button option, create a RadioButton in your layout. However, because radio buttons are mutually exclusive, you must group them together inside a RadioGroup. By grouping them together, the system ensures that only one radio button can be selected at a time.

How to do this?

RadioGroup is just like a view group for Radiobuttons so you can use it just like one

XML:

<?xml version="1.0" encoding="utf-8"?>
<RadioGroup xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<RadioButton android:id="@+id/radio_pirates"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/pirates"
    android:onClick="onRadioButtonClicked"/>
<RadioButton android:id="@+id/radio_ninjas"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/ninjas"
    android:onClick="onRadioButtonClicked"/>
</RadioGroup>

C#:

RadioGroup rg = new RadioGroup(this); //create the RadioGroup
rg.Orientation = Orientation.Horizontal;//or Orientation.VERTICAL
RadioButton rb = new RadioButton(this);// create the radiobutton
rg.AddView(rb);// add to radio group