无法在 xamarin android 上将 CustomAdapter 表达式转换为类型 System.Collections.Generic.List<string>

Question

string[] items = new string[] { "Alternative Rock","Classical", "Country"}

for (int i = 0; i <= items.Count(); i++) {
    mAdapter.addItem (items [i].ToString ());
    if (i == 0) {
     mAdapter.addSectionHeaderItem ("Music");
    } else if(i==13) {
     mAdapter.addSectionHeaderItem ("Audio");
    }
   }
   lst.Adapter = new CustomAdapter (Activity, mAdapter);

public class CustomAdapter : BaseAdapter{

 private  const int TYPE_ITEM = 0;
 private const int TYPE_SEPARATOR = 1;

 private List<string> mData;
 private TreeSet sectionHeader;

 private LayoutInflater mInflater;

 public CustomAdapter(Context context, List<string> mData) {
  mInflater = (LayoutInflater) context
   .GetSystemService(Context.LayoutInflaterService);
  this.mData=mData;
 }

 public void addItem( string item) {
  mData.Add(item);
  NotifyDataSetChanged();
 }

 public void addSectionHeaderItem(string item) {
  mData.Add(item);
  sectionHeader.Add(mData.Count - 1);
  NotifyDataSetChanged();
 }

 public int getItemViewType(int position) {
  return sectionHeader.Contains(position) ? TYPE_SEPARATOR : TYPE_ITEM;
 }


 public int getViewTypeCount {
  get{ return 2; }
 }


 public override int Count {
  get {return mData.Count;}
 }


 public override Java.Lang.Object GetItem(int position) {
  return null;
 }
  
 public override long GetItemId(int position) {
  return position;
 } 

 public View GetView(int position, View convertView, ViewGroup parent) {
  ViewHolder holder = null;
  int rowType = getItemViewType(position);

  if (convertView == null) {
   holder = new ViewHolder();
   switch (rowType) {
   case TYPE_ITEM:
    convertView = mInflater.Inflate(Resource.Layout.textViewItemsSeparator, parent);
    holder.textView = (TextView) convertView.FindViewById(Resource.Id.textviewHeaderItems);
    break;
   case TYPE_SEPARATOR:
    convertView = mInflater.Inflate(Resource.Layout.textViewHeaderItems, parent);
    holder.textView = (TextView) convertView.FindViewById(Resource.Id.textviewItemsSeparator);
    break;
   }
   convertView.Tag=holder;
  } else {
   holder = (ViewHolder)convertView.Tag as ViewHolder;
  }
  holder.textView.Text=mData[position];

  return convertView;
 }

 public  class ViewHolder:Java.Lang.Object {
  public TextView textView;
 }

无法将 CustomAdapter 表达式转换为类型 System.Collections.Generic.List on xamarin android at

CustomAdapter : BaseAdapter and new CustomAdapter (Activity, mAdapter); Blockquote

在这个例子中，我们将展示如何创建带有 header 部分的 ListView。这涉及以下步骤

更新我的 post.

Answer 1

您的 CustomAdapter 构造函数的签名指定了两个参数，一个上下文和一个 List<string>

public CustomAdapter(Context context, List<String> mData) {

但是，当您创建它时，您传递的是 mAdapter 作为第二个参数，而不是 List<string>。

lst.Adapter = new CustomAdapter (Activity, mAdapter);

无法在 xamarin android 上将 CustomAdapter 表达式转换为类型 System.Collections.Generic.List<string>

cannot convert CustomAdapter expression to type System.Collections.Generic.List<string> on xamarin android

xamarin.android

xamarin