Question

我正在开发这个应用程序，我在列表视图中有一个TextView和一个Checkbox。 ListView行的XMLS如下：

  <LinearLayout
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="8"
    android:orientation="vertical"
    android:id="@+id/linearLayout">

    <TextView
      android:text="Name"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:id="@+id/deliverNumberTextView"
      android:textSize="20dp"
      android:textColor="@android:color/black"
      android:padding="5dp" />

    <CheckBox
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_marginTop="10dp"
      android:id="@+id/listviewCheckbox"/>

  </LinearLayout>

我试图在ListView适配器中以编程方式选择TextView和Checkbox的值。以下是用于GetView（）覆盖的代码：

    public override View GetView (int position, View convertView, ViewGroup parent)
    {
        View row = convertView;

        if (row == null)
        {
            row = LayoutInflater.From (_context).Inflate (Resource.Layout.ListviewRow, null, false);
        }

        TextView deliverNumberTextView = (TextView) row.FindViewById (Resource.Id.deliverNumberTextView);

        CheckBox listviewCheckbox = (CheckBox)row.FindViewById(Resource.Id.listviewCheckbox);

        deliverNumberTextView.Text = _deliveries[position].DeliveryNumber;
        listviewCheckbox.Visibility = ViewStates.Visible;

        return row;
    }

问题是在执行此代码后，我获得了TextView的值，但是我无法更改Checkbox的可见性，因为“listviewCheckbox”为null。

感谢任何帮助。谢谢。

Answer 1

尝试这种方式::

public class ListAdapter: BaseAdapter
{

    // Make this variable global
     TextView deliverNumberTextView ;
     CheckBox listviewCheckbox

     public override View GetView (int position, View convertView, ViewGroup parent)
     { 
            View row = convertView;

            if (row == null)
            { 
                row = LayoutInflater.From (_context).Inflate (Resource.Layout.ListviewRow, null, false);
            } 

                deliverNumberTextView = (TextView) row.FindViewById (Resource.Id.deliverNumberTextView);

                listviewCheckbox = (CheckBox)row.FindViewById(Resource.Id.listviewCheckbox);

                deliverNumberTextView.Text = _deliveries[position].DeliveryNumber;
                listviewCheckbox.Visibility = ViewStates.Visible;

    return row;
    } 
}

无法从Listview内部选择Checkbox

1 个答案: