java - 安卓开发 : How do I integrate threads in this?

Question

所以我正在尝试通过从 youtube channel 检索 json 数据来制作一个 youtube 应用程序。问题是我很擅长编写单线程应用程序。但是当涉及到多线程时，我总是失去洞察力。

我还没有在学校学过，大多数教程都是垃圾，或者至少我发现了这一点。

所以我想做的是在我的“GetVideos”类中引入一个线程，这样它就不会在检索视频时减慢我的应用程序。我知道我必须使用处理程序和线程，但每次我尝试使用它们时，我的应用程序都会崩溃。你们能帮忙吗？

public class GetVideos { //class that retrieves JSON data based on youtube username

private String channelName;
private HttpClient client; //client that gets info
private VideoLibrary lib;


public GetVideos(String channelName) {
    this.channelName = channelName;
    client = new DefaultHttpClient();
    lib = new VideoLibrary();
    fillData();
}

private void fillData() {
    try {
        final String URL = "http://gdata.youtube.com/feeds/api/users/" + channelName + "/uploads?v=2&alt=jsonc";
        HttpGet get = new HttpGet(URL);
        HttpResponse response = client.execute(get);
        String jsonString = EntityUtils.toString(response.getEntity());
        JSONObject json = new JSONObject(jsonString);
        JSONArray jsonArray = json.getJSONObject("data").getJSONArray("items");
        for (int i = 0; i < jsonArray.length(); i++) {
            JSONObject items = jsonArray.getJSONObject(i);
            String title = items.getString("title");
            String thumbUrl = items.getJSONObject("thumbnail").getString("sqDefault");
            String url = items.getJSONObject("player").getString("default");
            lib.addVideo(new Video(title, url, thumbUrl));

        }

    } catch (JSONException e) {
        e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
    } catch (ClientProtocolException e) {
        e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
    } catch (IOException e) {
        e.printStackTrace();  
       }
   }

    public VideoLibrary getLib() {
         return lib;
    } 
 }

public class SxePhil extends Activity { //class that makes up the interactive end of
//the app, here the JSON data is put in a list 
private ListView list;
private GetVideos g;
private VideoLibrary videoLibrary;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.sxephil);
    list = (ListView) findViewById(R.id.sxephilList);
    g = new GetVideos("sxephil");
    videoLibrary = g.getLib();

    ArrayList<String> titles = new ArrayList<String>();
    for (int i = 0; i < 25; i++) {
        titles.add(videoLibrary.getVideos().get(i).getTitle());
    }


       ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.simplerow, titles);
        list.setAdapter(adapter);
   }  
}

基本上我尝试的是实现这里使用的线程:http://blog.blundell-apps.com/show-youtube-user-videos-in-a-listview/

在我的代码中，因为这个项目是建立在一个旧的 sdk 上的，所以我想可以说是对其进行现代化改造。看看GetYoutube***类和MainActivity类就是钱所在

Answer 1

您应该使用 AsyncTask甚至更好，Loader ，它们会自动为您处理胎面