Android一个Adapter的写法

public class NewsListAdapter extends BaseAdapter {

    private Context mContext;
    private LinkedList<NewsModel> newsList;

    public NewsListAdapter(Context mContext, LinkedList<NewsModel> newsList) {
        this.mContext = mContext;
        this.newsList = newsList == null ? new LinkedList<NewsModel>() : new LinkedList<>(newsList);
    }

    @Override
    public int getCount() {
        return newsList != null ? newsList.size() : 0;
    }

    @Override
    public Object getItem(int position) {
        return position >= newsList.size() ? null : newsList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        if (convertView == null) {
            convertView = LayoutInflater.from(mContext).inflate(R.layout.newslist_item, parent, false);
        }

        TextView newsTitleView = (TextView) convertView.findViewById(R.id.titleView);
        TextView newsAuthorView = (TextView) convertView.findViewById(R.id.authorView);
        TextView newsDateView = (TextView) convertView.findViewById(R.id.dateView);

        final NewsModel mNewsModel = newsList.get(position);
        newsTitleView.setText(mNewsModel.getTitle());
        newsAuthorView.setText("发布人：" + mNewsModel.getAuthor());
        newsDateView.setText("发布日期：" + new SimpleDateFormat("yyyy.MM.dd HH:mm:ss").format(mNewsModel.getDate()));

        return convertView;
    }

    public void updateData(LinkedList<NewsModel> dataList) {
        this.newsList = dataList;
        this.notifyDataSetChanged();
    }
}

package android.widget;

import android.database.DataSetObserver;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListAdapter;
import android.widget.SpinnerAdapter;

public abstract class BaseAdapter implements ListAdapter, SpinnerAdapter {
    public BaseAdapter() {
        throw new RuntimeException("Stub!");
    }

    public boolean hasStableIds() {
        throw new RuntimeException("Stub!");
    }

    public void registerDataSetObserver(DataSetObserver observer) {
        throw new RuntimeException("Stub!");
    }

    public void unregisterDataSetObserver(DataSetObserver observer) {
        throw new RuntimeException("Stub!");
    }

    public void notifyDataSetChanged() {
        throw new RuntimeException("Stub!");
    }

    public void notifyDataSetInvalidated() {
        throw new RuntimeException("Stub!");
    }

    public boolean areAllItemsEnabled() {
        throw new RuntimeException("Stub!");
    }

    public boolean isEnabled(int position) {
        throw new RuntimeException("Stub!");
    }

    public View getDropDownView(int position, View convertView, ViewGroup parent) {
        throw new RuntimeException("Stub!");
    }

    public int getItemViewType(int position) {
        throw new RuntimeException("Stub!");
    }

    public int getViewTypeCount() {
        throw new RuntimeException("Stub!");
    }

    public boolean isEmpty() {
        throw new RuntimeException("Stub!");
    }
}

package android.widget;

import android.widget.Adapter;

public interface ListAdapter extends Adapter {
    boolean areAllItemsEnabled();

    boolean isEnabled(int var1);
}

package android.widget;

import android.database.DataSetObserver;
import android.view.View;
import android.view.ViewGroup;

public interface Adapter {
    int IGNORE_ITEM_VIEW_TYPE = -1;
    int NO_SELECTION = -2147483648;

    void registerDataSetObserver(DataSetObserver var1);

    void unregisterDataSetObserver(DataSetObserver var1);

    int getCount();

    Object getItem(int var1);

    long getItemId(int var1);

    boolean hasStableIds();

    View getView(int var1, View var2, ViewGroup var3);

    int getItemViewType(int var1);

    int getViewTypeCount();

    boolean isEmpty();
}

package android.widget;

import android.view.View;
import android.view.ViewGroup;
import android.widget.Adapter;

public interface SpinnerAdapter extends Adapter {
    View getDropDownView(int var1, View var2, ViewGroup var3);
}