私はアンドロイド開発には新しく、私はjsonデータで遊んでいます。私は構文解析を機能させることができた。私はProgressDialogを表示したい、私はAsyncTaskを使う必要があることを読んでいる。しかし、何らかの理由で、doInBackground()内に同じ作業コードを入れると、すぐに力を得ることができます。ここでバックグラウンドでAsyncTaskを使用してJSONを解析しようとすると強制終了します
は、ソースコードである:
01-08 12:33:48.225: ERROR/AndroidRuntime(815): FATAL EXCEPTION: AsyncTask #1
01-08 12:33:48.225: ERROR/AndroidRuntime(815): java.lang.RuntimeException: An error occured while executing doInBackground()
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.os.AsyncTask$3.done(AsyncTask.java:200)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:274)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at java.util.concurrent.FutureTask.setException(FutureTask.java:125)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:308)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at java.util.concurrent.FutureTask.run(FutureTask.java:138)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1088)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:581)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at java.lang.Thread.run(Thread.java:1019)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): Caused by: android.view.ViewRoot$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.view.ViewRoot.checkThread(ViewRoot.java:2932)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.view.ViewRoot.requestLayout(ViewRoot.java:629)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.view.View.requestLayout(View.java:8267)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.view.View.requestLayout(View.java:8267)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.view.View.requestLayout(View.java:8267)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.view.View.requestLayout(View.java:8267)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.view.View.requestLayout(View.java:8267)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.widget.TextView.checkForRelayout(TextView.java:5521)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.widget.TextView.setText(TextView.java:2724)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.widget.TextView.setText(TextView.java:2592)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.widget.TextView.setText(TextView.java:2567)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at net.ajzele.demo.andy1.HomeActivity$BackgroundAsyncTask.doInBackground(HomeActivity.java:52)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at net.ajzele.demo.andy1.HomeActivity$BackgroundAsyncTask.doInBackground(HomeActivity.java:1)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at android.os.AsyncTask$2.call(AsyncTask.java:185)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:306)
01-08 12:33:48.225: ERROR/AndroidRuntime(815): ... 4 more
01-08 12:33:51.605: ERROR/WindowManager(815): Activity net.ajzele.demo.andy1.HomeActivity has leaked window [email protected] that was originally added here
01-08 12:33:51.605: ERROR/WindowManager(815): android.view.WindowLeaked: Activity net.ajzele.demo.andy1.HomeActivity has leaked window [email protected] that was originally added here
01-08 12:33:51.605: ERROR/WindowManager(815): at android.view.ViewRoot.<init>(ViewRoot.java:258)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:148)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.view.Window$LocalWindowManager.addView(Window.java:424)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.app.Dialog.show(Dialog.java:241)
01-08 12:33:51.605: ERROR/WindowManager(815): at net.ajzele.demo.andy1.HomeActivity$BackgroundAsyncTask.onPreExecute(HomeActivity.java:33)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.os.AsyncTask.execute(AsyncTask.java:391)
01-08 12:33:51.605: ERROR/WindowManager(815): at net.ajzele.demo.andy1.HomeActivity.onCreate(HomeActivity.java:72)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1586)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1638)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.app.ActivityThread.access$1500(ActivityThread.java:117)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:928)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.os.Handler.dispatchMessage(Handler.java:99)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.os.Looper.loop(Looper.java:123)
01-08 12:33:51.605: ERROR/WindowManager(815): at android.app.ActivityThread.main(ActivityThread.java:3647)
01-08 12:33:51.605: ERROR/WindowManager(815): at java.lang.reflect.Method.invokeNative(Native Method)
01-08 12:33:51.605: ERROR/WindowManager(815): at java.lang.reflect.Method.invoke(Method.java:507)
01-08 12:33:51.605: ERROR/WindowManager(815): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
01-08 12:33:51.605: ERROR/WindowManager(815): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
01-08 12:33:51.605: ERROR/WindowManager(815): at dalvik.system.NativeStart.main(Native Method)
任意のヒント:ここで
public class HomeActivity extends Activity {
public class BackgroundAsyncTask extends AsyncTask<Void, Integer, Void> {
ProgressDialog dialog = new ProgressDialog (HomeActivity.this);
@Override
protected void onPreExecute() {
dialog.setMessage("Loading...please wait");
dialog.setIndeterminate(true);
dialog.setCancelable(false);
dialog.show();
}
protected void onPostExecute() {
dialog.dismiss();
}
@Override
protected Void doInBackground(Void... params) {
try {
URL json = new URL("http://www.corps-marchia.de/jsontest.php");
URLConnection tc = json.openConnection();
BufferedReader in = new BufferedReader(new InputStreamReader(tc.getInputStream()));
String line;
while ((line = in.readLine()) != null) {
JSONArray ja = new JSONArray(line);
JSONObject jo = (JSONObject) ja.get(0);
TextView txtView = (TextView)findViewById(R.id.TextView01);
txtView.setText(jo.getString("text"));
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
new BackgroundAsyncTask().execute();
}
}
は、エラーログのですか?私は、おかげで事前
ありがとう!その魅力のように働く!私はあなたが背景からUIの変更を行うことができなかったとは考えていませんでした。 dialog.dismiss()はonPostExecute()から動作していませんが、何らかの理由がありますか?進行状況ダイアログもUIとしてカウントされますか? – robs
ダイアログが不明です。おそらく[showDialog](http://developer.android.com/reference/android/app/Activity.html#showDialog(int))を[onCreateDialog](http://developer.android.com)と組み合わせて試してみてください。 /reference/android/app/Activity.html#onCreateDialog(int))。ダイアログのHersの[記事](http://developer.android.com/guide/topics/ui/dialogs.html) –
[documentation](http://developer.android.com/reference/android/app/Dialog.html#dismiss%28%29)は、「dismiss」はどのスレッドからも安全に呼び出すことができると述べています。確かに何が間違っている。 –