以下のコードを使用して JSON データを解析しようとしています。Web サイトには API キーが必要です。これは今のところ、strings.xml に文字列として保存されています。
public class JSONParser {
static InputStream is = null;
static JSONArray jarray = null;
static String json = "";
// constructor
public JSONParser() {
}
public JSONArray getJSONFromUrl(String url) {
// Making HTTP request
try {
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
try {
JSONObject jObj = new JSONObject(json);
jarray = jObj.getJSONArray("systems");
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
return jarray;
}
}
主な活動。
public class MainActivity extends ListActivity {
private Context context;
private static String url = "https://api.company.com/api/systems";
private static final String TAG_SYSTEM = "systems";
private static final String TAG_SYSTEM_ID = "system_id";
ArrayList<HashMap<String, String>> jsonlist = new ArrayList<HashMap<String, String>>();
ListView lv ;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new ProgressTask(MainActivity.this).execute();
}
private class ProgressTask extends AsyncTask<String, Void, Boolean> {
private ProgressDialog dialog;
private ListActivity activity;
// private List<Message> messages;
public ProgressTask(ListActivity activity) {
this.activity = activity;
context = activity;
dialog = new ProgressDialog(context);
}
/** progress dialog to show user that the backup is processing. */
private Context context;
protected void onPreExecute() {
this.dialog.setMessage("Progress start");
this.dialog.show();
}
@Override
protected void onPostExecute(final Boolean success) {
if (dialog.isShowing()) {
dialog.dismiss();
}
ListAdapter adapter = new SimpleAdapter(context, jsonlist,
R.layout.list_item, new String[] { TAG_SYSTEM, TAG_SYSTEM_ID
}, new int[] {
R.id.vehicleType, R.id.vehicleColor });
setListAdapter(adapter);
// selecting single ListView item
lv = getListView();
}
protected Boolean doInBackground(final String... args) {
JSONParser jParser = new JSONParser();
//Using APIKEY from strings.xml
String apikey = getString(R.string.apikey);
// getting JSON string from URL
JSONArray json = jParser.getJSONFromUrl(url + "&key=" + apikey);
for (int i = 0; i < json.length(); i++) {
try {
JSONObject c = json.getJSONObject(i);
String vcolor = c.getString(TAG_SYSTEM_ID);
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(TAG_SYSTEM_ID, vcolor);
jsonlist.add(map);
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return null;
}
}
}
これが私の現在のLogCatです
04-30 15:39:53.775: E/JSON Parser(9814): Error parsing data org.json.JSONException: Value <!DOCTYPE of type java.lang.String cannot be converted to JSONObject
04-30 15:39:53.780: E/AndroidRuntime(9814): FATAL EXCEPTION: AsyncTask #1
04-30 15:39:53.780: E/AndroidRuntime(9814): java.lang.RuntimeException: An error occured while executing doInBackground()
04-30 15:39:53.780: E/AndroidRuntime(9814): at android.os.AsyncTask$3.done(AsyncTask.java:299)
04-30 15:39:53.780: E/AndroidRuntime(9814): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
04-30 15:39:53.780: E/AndroidRuntime(9814): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
04-30 15:39:53.780: E/AndroidRuntime(9814): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
04-30 15:39:53.780: E/AndroidRuntime(9814): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
04-30 15:39:53.780: E/AndroidRuntime(9814): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
04-30 15:39:53.780: E/AndroidRuntime(9814): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
04-30 15:39:53.780: E/AndroidRuntime(9814): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
04-30 15:39:53.780: E/AndroidRuntime(9814): at java.lang.Thread.run(Thread.java:856)
04-30 15:39:53.780: E/AndroidRuntime(9814): Caused by: java.lang.NullPointerException
04-30 15:39:53.780: E/AndroidRuntime(9814): at com.jitesh.androidjsonparser.MainActivity$ProgressTask.doInBackground(MainActivity.java:102)
04-30 15:39:53.780: E/AndroidRuntime(9814): at com.jitesh.androidjsonparser.MainActivity$ProgressTask.doInBackground(MainActivity.java:1)
04-30 15:39:53.780: E/AndroidRuntime(9814): at android.os.AsyncTask$2.call(AsyncTask.java:287)
04-30 15:39:53.780: E/AndroidRuntime(9814): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
04-30 15:39:53.780: E/AndroidRuntime(9814): ... 5 more
04-30 15:40:03.035: E/WindowManager(9814): Activity com.jitesh.androidjsonparser.MainActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@4257ae80 that was originally added here
04-30 15:40:03.035: E/WindowManager(9814): android.view.WindowLeaked: Activity com.jitesh.androidjsonparser.MainActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@4257ae80 that was originally added here
04-30 15:40:03.035: E/WindowManager(9814): at android.view.ViewRootImpl.<init>(ViewRootImpl.java:402)
04-30 15:40:03.035: E/WindowManager(9814): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:311)
04-30 15:40:03.035: E/WindowManager(9814): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:224)
04-30 15:40:03.035: E/WindowManager(9814): at android.view.WindowManagerImpl$CompatModeWrapper.addView(WindowManagerImpl.java:149)
04-30 15:40:03.035: E/WindowManager(9814): at android.view.Window$LocalWindowManager.addView(Window.java:554)
04-30 15:40:03.035: E/WindowManager(9814): at android.app.Dialog.show(Dialog.java:277)
04-30 15:40:03.035: E/WindowManager(9814): at com.jitesh.androidjsonparser.MainActivity$ProgressTask.onPreExecute(MainActivity.java:69)
04-30 15:40:03.035: E/WindowManager(9814): at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
04-30 15:40:03.035: E/WindowManager(9814): at android.os.AsyncTask.execute(AsyncTask.java:534)
04-30 15:40:03.035: E/WindowManager(9814): at com.jitesh.androidjsonparser.MainActivity.onCreate(MainActivity.java:47)
04-30 15:40:03.035: E/WindowManager(9814): at android.app.Activity.performCreate(Activity.java:5206)
04-30 15:40:03.035: E/WindowManager(9814): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1083)
04-30 15:40:03.035: E/WindowManager(9814): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2064)
04-30 15:40:03.035: E/WindowManager(9814): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2125)
04-30 15:40:03.035: E/WindowManager(9814): at android.app.ActivityThread.access$600(ActivityThread.java:140)
04-30 15:40:03.035: E/WindowManager(9814): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1227)
04-30 15:40:03.035: E/WindowManager(9814): at android.os.Handler.dispatchMessage(Handler.java:99)
04-30 15:40:03.035: E/WindowManager(9814): at android.os.Looper.loop(Looper.java:137)
04-30 15:40:03.035: E/WindowManager(9814): at android.app.ActivityThread.main(ActivityThread.java:4898)
04-30 15:40:03.035: E/WindowManager(9814): at java.lang.reflect.Method.invokeNative(Native Method)
04-30 15:40:03.035: E/WindowManager(9814): at java.lang.reflect.Method.invoke(Method.java:511)
04-30 15:40:03.035: E/WindowManager(9814): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006)
04-30 15:40:03.035: E/WindowManager(9814): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773)
04-30 15:40:03.035: E/WindowManager(9814): at dalvik.system.NativeStart.main(Native Method)
誰かがこれらの問題を解決するのを手伝ってくれませんか。時間をかけて読んで助けていただければ、事前に感謝します。