Android應用開發-小巫CSDN博客客戶端之獲取評論列表

Android應用開發-小巫CSDN博客客戶端之獲取評論列表
上一篇博客介紹了博文詳細內容的業務邏輯實現，本篇博客介紹小巫CSDN博客客戶端的最後一項功能，獲取評論列表，這個功能的實現跟前面獲取文章列表和文章詳細的內容不一樣，CSDN博客獲取評論是通過js來請求服務器加載評論列表的，返回數據為json數據，我們這裡要做的事情就是找到這樣的一個js文件，再找到請求url的拼接字符串，然後根據我們的需求，請求文章的評論列表獲取到當前文章的評論json數據，然後進行解析工作，最後展示到我們的界面當中。 如果沒有仔細分析html代碼的童鞋，可能發現不了這一點，小巫在開發這個客戶端的時候，一時也獲取不到評論列表，後來通過與CSDN技術的交流之後，我再仔細查看才找到了關於博客的請求方式，這裡使用jsoup無法模擬javascript的加載，所以只能通過自己查看js代碼，找到請求的url，下面筆者會告訴大家怎麼來做這件事。
小巫這裡找一篇有評論的博文，比如以下這篇： http://blog.csdn.net/wwj_748/article/details/39726051
vcq9o6xGMTKy6b+01LS0+sLro6y78tXfsum/tNSqy9i2qM67tb3GwMLbxNrI3aOsyOfPwsv5yr6jujxpbWcgc3JjPQ=="/uploadfile/Collfiles/20141011/2014101108342887.jpg" alt="\" />


這時我們點擊進去查看相應的js文件，去看看能不能找到我們想要的東西：
哎呀，很不小心就被我發現了我想要的東西：

從上面我們可以分析出，獲取文章的評論列表需要請求類似以下的地址："http://blog.csdn.net/wwj_748/comment/list/39726051?page=1，剛開始小巫並不知道這樣的請求地址，是通過以上的方式才得知的。我們請求一篇文章需要知道對應文章的filename和pageIndex,然後以下面這種形式拼接：

/**
	 * 返回博文評論列表鏈接
	 * 
	 * @param filename
	 *            文件名
	 * @param pageIndex
	 *            頁數
	 * @return
	 */
	public static String getCommentListURL(String filename, String pageIndex) {
		return "http://blog.csdn.net/wwj_748/comment/list/" + filename
				+ "?page=" + pageIndex;
	}

到了這一步基本上解決了最麻煩的事情，下面是業務邏輯的實現：/BlogClient/src/com/xiaowu/blogclient/BlogCommentActivity.java

package com.xiaowu.blogclient;

import java.util.List;

import me.maxwin.view.IXListViewLoadMore;
import me.maxwin.view.IXListViewRefreshListener;
import me.maxwin.view.XListView;
import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;

import com.xiaowu.blogclient.adapter.CommentAdapter;
import com.xiaowu.blogclient.model.Comment;
import com.xiaowu.blogclient.model.Page;
import com.xiaowu.blogclient.util.Constants;
import com.xiaowu.blogclient.util.DateUtil;
import com.xiaowu.blogclient.util.HttpUtil;
import com.xiaowu.blogclient.util.JsoupUtil;
import com.xiaowu.blogclient.util.URLUtil;

/**
 * 2014/8/13
 * 
 * 博客評論列表
 * 
 * @author wwj_748
 * 
 */
public class BlogCommentActivity extends Activity implements
		IXListViewRefreshListener, IXListViewLoadMore {

	private XListView listView;
	private CommentAdapter adapter;

	private ProgressBar progressBar;
	private ImageView reLoadImageView;

	private ImageView backBtn;
	private TextView commentTV;

	public static String commentCount = "";
	private Page page;
	private String filename;
	private int pageIndex = 1;
	private int pageSize = 20;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		requestWindowFeature(Window.FEATURE_NO_TITLE);
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_comment);

		init();
		initComponent();

		listView.setRefreshTime(DateUtil.getDate()); // 設置刷新時間
		listView.startRefresh(); // 開始刷新
	}

	// 初始化
	private void init() {
		filename = getIntent().getExtras().getString("filename"); // 獲得文件名
		page = new Page();
		adapter = new CommentAdapter(this);
	}

	// 初始化組件
	private void initComponent() {
		progressBar = (ProgressBar) findViewById(R.id.newsContentPro);
		reLoadImageView = (ImageView) findViewById(R.id.reLoadImage);
		reLoadImageView.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				System.out.println("click");
				reLoadImageView.setVisibility(View.INVISIBLE);
				progressBar.setVisibility(View.VISIBLE);
				new MainTask().execute(Constants.DEF_TASK_TYPE.REFRESH);
			}
		});

		backBtn = (ImageView) findViewById(R.id.backBtn);
		backBtn.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				finish();
			}
		});
		commentTV = (TextView) findViewById(R.id.comment);

		listView = (XListView) findViewById(R.id.listview);
		listView.setAdapter(adapter);
		listView.setPullRefreshEnable(this);
		listView.setPullLoadEnable(this);
		listView.setOnItemClickListener(new OnItemClickListener() {

			@Override
			public void onItemClick(AdapterView parent, View view,
					int position, long id) {

			}
		});

	}

	@Override
	public void finish() {
		super.finish();
		// 退出動畫
		overridePendingTransition(R.anim.push_no, R.anim.push_right_out);
	}

	private class MainTask extends AsyncTask {

		@Override
		protected Integer doInBackground(String... params) {
			// 獲得返回json字符串
			String temp = HttpUtil.httpGet(URLUtil.getCommentListURL(filename,
					page.getCurrentPage()));
			if (temp == null) {
				return Constants.DEF_RESULT_CODE.ERROR;
			}
			// 獲得評論列表
			List list = JsoupUtil.getBlogCommentList(temp,
					Integer.valueOf(page.getCurrentPage()), pageSize);
			if (list.size() == 0) {
				return Constants.DEF_RESULT_CODE.NO_DATA;
			}

			if (params[0].equals(Constants.DEF_TASK_TYPE.LOAD)) {
				adapter.addList(list);
				return Constants.DEF_RESULT_CODE.LOAD;
			} else {
				adapter.setList(list);
				return Constants.DEF_RESULT_CODE.REFRESH;
			}
		}

		@Override
		protected void onPostExecute(Integer result) {
			if (result == Constants.DEF_RESULT_CODE.ERROR) {
				Toast.makeText(getApplicationContext(), "網絡信號不佳",
						Toast.LENGTH_SHORT).show();
				listView.stopRefresh(DateUtil.getDate());
				listView.stopLoadMore();
				reLoadImageView.setVisibility(View.VISIBLE);
			} else if (result == Constants.DEF_RESULT_CODE.NO_DATA) {
				Toast.makeText(getApplicationContext(), "無更多評論",
						Toast.LENGTH_SHORT).show();
				listView.stopLoadMore();
				listView.stopRefresh(DateUtil.getDate());
				commentTV.setText("共有評論：" + commentCount);
			} else if (result == Constants.DEF_RESULT_CODE.LOAD) {
				page.addPage();
				pageIndex++;
				adapter.notifyDataSetChanged();
				listView.stopLoadMore();
			} else if (result == Constants.DEF_RESULT_CODE.REFRESH) {
				adapter.notifyDataSetChanged();
				listView.stopRefresh(DateUtil.getDate());
				page.setPage(2);
				commentTV.setText("共有評論：" + commentCount); // 顯示評論數
			}
			progressBar.setVisibility(View.INVISIBLE);
			super.onPostExecute(result);
		}
	}

	// 加載更多
	@Override
	public void onLoadMore() {
		new MainTask().execute(Constants.DEF_TASK_TYPE.LOAD);
	}

	// 刷新評論
	@Override
	public void onRefresh() {
		page.setPage(1);
		new MainTask().execute(Constants.DEF_TASK_TYPE.REFRESH);
	}
}

/BlogClient/src/com/xiaowu/blogclient/adapter/CommentAdapter.java

package com.xiaowu.blogclient.adapter;

import java.util.ArrayList;
import java.util.List;

import android.content.Context;
import android.graphics.Bitmap;
import android.text.Html;
import android.text.SpannableStringBuilder;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;
import com.nostra13.universalimageloader.core.assist.ImageScaleType;
import com.nostra13.universalimageloader.core.display.FadeInBitmapDisplayer;
import com.xiaowu.blogclient.R;
import com.xiaowu.blogclient.model.Comment;
import com.xiaowu.blogclient.util.Constants;

/**
 * 評論列表適配器
 * 
 * @author wwj_748
 * 
 */
public class CommentAdapter extends BaseAdapter {
	private ViewHolder holder;
	private LayoutInflater layoutInflater;
	private Context context;
	private List list;

	private SpannableStringBuilder htmlSpannable;

	private ImageLoader imageLoader = ImageLoader.getInstance();
	private DisplayImageOptions options;
	
	private String replyText;

	public CommentAdapter(Context c) {
		super();
		layoutInflater = (LayoutInflater) LayoutInflater.from(c);
		list = new ArrayList();

		imageLoader.init(ImageLoaderConfiguration.createDefault(c));
		options = new DisplayImageOptions.Builder()
				.showStubImage(R.drawable.csdn)
				.showImageForEmptyUri(R.drawable.csdn)
				.showImageOnFail(R.drawable.csdn)
				.cacheInMemory().cacheOnDisc()
				.imageScaleType(ImageScaleType.EXACTLY)
				.bitmapConfig(Bitmap.Config.RGB_565)
				.displayer(new FadeInBitmapDisplayer(300)).build();
	}

	public void setList(List list) {
		this.list = list;
	}

	public void addList(List list) {
		this.list.addAll(list);
	}

	public void clearList() {
		this.list.clear();
	}

	public List getList() {
		return list;
	}

	public void removeItem(int position) {
		if (list.size() > 0) {
			list.remove(position);
		}
	}

	@Override
	public int getCount() {
		return list.size();
	}

	@Override
	public Object getItem(int position) {
		return list.get(position);
	}

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

	@Override
	public View getView(int position, View convertView, ViewGroup parent) {
		Comment item = list.get(position); // 獲取評論項
		if (null == convertView) {
			holder = new ViewHolder();
			switch (item.getType()) {
			case Constants.DEF_COMMENT_TYPE.PARENT: // 父項
				convertView = layoutInflater.inflate(R.layout.comment_item,
						null);
				holder.name = (TextView) convertView.findViewById(R.id.name);
				holder.content = (TextView) convertView
						.findViewById(R.id.content);
				holder.date = (TextView) convertView.findViewById(R.id.date);
				holder.reply = (TextView) convertView
						.findViewById(R.id.replyCount);
				holder.userface = (ImageView) convertView.findViewById(R.id.userface);
				
				break;
			case Constants.DEF_COMMENT_TYPE.CHILD: // 子項
				convertView = layoutInflater.inflate(
						R.layout.comment_child_item, null);
				holder.name = (TextView) convertView.findViewById(R.id.name);
				holder.content = (TextView) convertView
						.findViewById(R.id.content);
				holder.date = (TextView) convertView.findViewById(R.id.date);
				break;
			}
			convertView.setTag(holder);
		} else {
			holder = (ViewHolder) convertView.getTag();
		}

		if (null != item) {
			switch (item.getType()) {
			case Constants.DEF_COMMENT_TYPE.PARENT: // 主題項
				holder.name.setText(item.getUsername()); 
				holder.content.setText(Html.fromHtml(item.getContent())); // 顯示評論內容
				holder.date.setText(item.getPostTime());
//				holder.reply.setText(item.getReplyCount());
				imageLoader.displayImage(item.getUserface(), holder.userface, options);// 顯示頭像
				break;
			case Constants.DEF_COMMENT_TYPE.CHILD: // 回復項
				holder.name.setText(item.getUsername());
				replyText = item.getContent().replace("[reply]", "【");
				replyText = replyText.replace("[/reply]", "】");
				holder.content.setText(Html.fromHtml(replyText));
				holder.date.setText(item.getPostTime());
				break;
			default:
				break;
			}
		}
		return convertView;
	}

	@Override
	public int getViewTypeCount() {
		return 2;
	}

	@Override
	public int getItemViewType(int position) {
		switch (list.get(position).getType()) {
		case Constants.DEF_COMMENT_TYPE.PARENT: // 父節點
			return 0;
		case Constants.DEF_COMMENT_TYPE.CHILD: // 子節點
			return 1;
		}
		return 1;
	}

	@Override
	public boolean isEnabled(int position) {
		return true;
	}

	private class ViewHolder {
		TextView id;
		TextView date;
		TextView name;
		TextView content;
		ImageView userface;
		TextView reply;
	}
}

最終效果圖如下： 源碼查看： http://download.csdn.net/detail/wwj_748/7912513