ここからチュートリアルを採用して、JSONを介してYouTubeチャンネルから動画を取得しました。すべてが正常に機能していますが、ビデオがバックグラウンドスレッドに読み込まれている間に、ProgressDialogを追加したいと思いました。バックグラウンドスレッドがAsyncTaskによって処理される場合、ProgressDialogを追加する方法は知っていますが、この場合の方法がわかりません。
コードの重要な部分は次のとおりです。
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_video);
listView = (VideosListView) findViewById(R.id.videosListView);
listView.setOnVideoClickListener(this);
getUserYouTubeFeed((VideosListView) findViewById(R.id.videosListView));
}
// This is the XML onClick listener to retreive a users video feed
public void getUserYouTubeFeed(View v){
// We start a new task that does its work on its own thread
// We pass in a handler that will be called when the task has finished
// We also pass in the name of the user we are searching YouTube for
new GetYouTubeUserVideosTask(responseHandler, "videoslusofona").run();
}
// This is the handler that receives the response when the YouTube task has finished
Handler responseHandler = new Handler() {
public void handleMessage(Message msg) {
populateListWithVideos(msg);
};
};
そのため、開いているビデオを一覧表示するアクティビティがあり、その上にandroid:onClick=getUserYouTubeFeed、ユーザーが必要に応じて更新できるように、XMLレイアウトのボタンがあります。ProgressDialogは、アクティビティの開始時とユーザーが更新ボタンを押したときにアクティブになる場所に配置するという考え方です。
ProgressDialogをどこに置くべきかについて教えていただければ幸いです。
前もって感謝します。
編集：
Pratik Sharmaによって提案された変更を加えたアクティビティ全体のコード：
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import com.example.igestao.youtube.GetYouTubeUserVideosTask;
import com.example.igestao.R;
import com.example.igestao.youtube.Library;
import com.example.igestao.youtube.Video;
import com.example.igestao.youtube.VideoClickListener;
import com.example.igestao.youtube.VideosListView;
/**
* The Activity can retrieve Videos for a specific username from YouTube</br>
* It then displays them into a list including the Thumbnail preview and the title</br>
* There is a reference to each video on YouTube as well but this isn't used in this tutorial</br>
* </br>
* <b>Note<b/> orientation change isn't covered in this tutorial, you will want to override
* onSaveInstanceState() and onRestoreInstanceState() when you come to this
* </br>
* @author paul.blundell
*/
public class MainVideoActivity extends Activity implements VideoClickListener {
// A reference to our list that will hold the video details
private VideosListView listView;
ProgressDialog dialog = new ProgressDialog(MainVideoActivity.this);
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_video);
listView = (VideosListView) findViewById(R.id.videosListView);
listView.setOnVideoClickListener(this);
getUserYouTubeFeed((VideosListView) findViewById(R.id.videosListView));
}
// This is the XML onClick listener to retreive a users video feed
public void getUserYouTubeFeed(View v){
// We start a new task that does its work on its own thread
// We pass in a handler that will be called when the task has finished
// We also pass in the name of the user we are searching YouTube for
new VideosLoad().execute();
}
// This is the handler that receives the response when the YouTube task has finished
Handler responseHandler = new Handler() {
public void handleMessage(Message msg) {
if (dialog.isShowing()){
dialog.dismiss();
}
populateListWithVideos(msg);
};
};
/**
* This method retrieves the Library of videos from the task and passes them to our ListView
* @param msg
*/
private void populateListWithVideos(Message msg) {
// Retreive the videos are task found from the data bundle sent back
Library lib = (Library) msg.getData().get(GetYouTubeUserVideosTask.LIBRARY);
// Because we have created a custom ListView we don't have to worry about setting the adapter in the activity
// we can just call our custom method with the list of items we want to display
listView.setVideos(lib.getVideos());
}
@Override
protected void onStop() {
// Make sure we null our handler when the activity has stopped
// because who cares if we get a callback once the activity has stopped? not me!
responseHandler = null;
super.onStop();
}
@Override
public void onVideoClicked(Video video) {
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setData(Uri.parse(video.getUrl()));
startActivity(intent);
}
private class VideosLoad extends AsyncTask<Void, Void, String>{
@Override
protected String doInBackground(Void... arg0){
new GetYouTubeUserVideosTask(responseHandler, "videoslusofona").run();
return "Executed";
}
@Override
protected void onPreExecute() {
dialog.setMessage("Carregando Videos");
dialog.show();
}
}
}