android - 如何创建带有部分标题的 Android ListView xamarin android？我有 17 个错误

Question

在此示例中，我们将展示如何创建带有节标题的 ListView。这涉及以下步骤

为您的列表标题和列表行创建两个自定义布局为 ListView 创建自定义适配器在您的 Activity 中实例化 ListView

我有 17 个错误。我想用节头 xamarin android 创建 ListView 。 http://javatechig.com/android/listview-with-section-header-in-android

我从java转换成C#

>  - `public class CustomAdapter:BaseAdapter`->does not implement abstract member `android.widget.baseAdapter.getitem(int)`
>  - `Android.Widget.BaseAdapter.NotifyDataSetChanged ()`-> An object reference is requered to access non-static member .....
>  - `return mData.GetRange(position)`;-> no overload for method 'getrange'take 1 arguments
>  - `convertView = mInflater.Inflate(Resource.Layout.textViewHeaderItems, false)`;-> the
> best overloaded method match for ..... has some invalid arguments
>  - `convertView.SetTag(holder);`-> no overload for method ... tkae 2 arguments
>  - `holder.textView.SetText(mData.get(position))`; type system.collection.generic.list<string> does not contain a defintion
> for 'get'and no extension method 'get'of type
> `system.Colleciton.Generic.List<string>` could be found. Are you
> missing an assembly

public class CustomAdapter:BaseAdapter
		{
			private  const int TYPE_ITEM = 0;
			private  const int TYPE_SEPARATOR = 1;

			private List<String> mData = new List<String>();
			private TreeSet sectionHeader = new TreeSet();

			private LayoutInflater mInflater;

			public CustomAdapter(Context context) {
				mInflater = (LayoutInflater) context
					.GetSystemService(Context.LayoutInflaterService);
			}

			public void addItem(String item) {
				mData.Add(item);
				Android.Widget.BaseAdapter.NotifyDataSetChanged ();
			}

			public void addSectionHeaderItem(String item) {
				mData.Add(item);
				sectionHeader.Add(mData.Count - 1);
				Android.Widget.BaseAdapter.NotifyDataSetChanged ();
			}

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

	
			public int getViewTypeCount() {
				return 2;
			}

	
			public int getCount() {
				return mData.Count;
			}

		
			public String getItem(int position) {
				return mData.GetRange(position);
			}

		
			public 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.textViewHeaderItems, false);
						holder.textView = (TextView) convertView.FindViewById(Resource.Id.textviewHeaderItems);
						break;
					case TYPE_SEPARATOR:
						convertView = mInflater.Inflate(Resource.Layout.textViewItemsSeparator, false);
						holder.textView = (TextView) convertView.FindViewById(Resource.Id.textviewItemsSeparator);
						break;
					}
					convertView.SetTag(holder);
				} else {
					holder = (ViewHolder) convertView.GetTag();
				}
				holder.textView.SetText(mData.get(position));

				return convertView;
			}

			public class ViewHolder {
				public TextView textView;
			}
		}

Answer 1

您应该使用 Xamarin 开发站点上的“搜索”功能来解决以下问题:

• https://developer.xamarin.com

注意:对于此类问题，Google 或 Bing 也是您最好的 friend 。

Android.Content.Context.LayoutInflaterService

Use with Context.GetSystemService(String) to retrieve a LayoutInflater for inflating layout resources in this context.

https://developer.xamarin.com/api/field/Android.Content.Context.LayoutInflaterService/

Android.Widget.BaseAdapter.NotifyDataSetChanged

Notifies the attached observers that the underlying data has been changed and any View reflecting the data set should refresh itself.

https://developer.xamarin.com/api/member/Android.Widget.BaseAdapter.NotifyDataSetChanged/

Java.Util.TreeSet

TreeSet is an implementation of SortedSet.

https://developer.xamarin.com/api/type/Java.Util.TreeSet/