我正在尝试用json创建列表视图。
这是Logcat Stacktrace
1215-1239/com.skripsi.mazdamobil E/AndroidRuntime﹕ FATAL EXCEPTION: AsyncTask #1
java.lang.RuntimeException: An error occured while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:299)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
at java.util.concurrent.FutureTask.run(FutureTask.java:239)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
at java.lang.Thread.run(Thread.java:841)
Caused by: java.lang.NullPointerException
at com.skripsi.mazdamobil.Data_Tipsntrick$DownloadList.doInBackground(Data_Tipsntrick.java:186)
at com.skripsi.mazdamobil.Data_Tipsntrick$DownloadList.doInBackground(Data_Tipsntrick.java:164)
at android.os.AsyncTask$2.call(AsyncTask.java:287)
at java.util.concurrent.FutureTask.run(FutureTask.java:234)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
at java.lang.Thread.run(Thread.java:841)
Data_Tipsntrick.java:164
private class DownloadList extends AsyncTask<Void,Void,Void> <- line 164
{
protected void onPreExecute()
{
super.onPreExecute();
pDialog = new ProgressDialog(Data_Tipsntrick.this);
pDialog.setMessage("Tunggu Sebentar...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
Data_Tipsntrick.java:186
protected Void doInBackground(Void... unused)
{
String url_param;
url_param="fungsi.php?pl="+filepl+"&kategori="+filekategori;
JSONParser jParser = new JSONParser();
JSONObject json = jParser.getJSONFromUrl(url+url_param);
Log.d("log", "url:" + url + url_param);
try
{
JSONArray result = json.getJSONArray("result"); <<-- line 186
for (int i = 0; i < result.length(); i++)
{
JSONObject c = result.getJSONObject(i);
String id = c.getString("id");
String pesan = c.getString("pesan");
String nama_tipsntrick = c.getString("nama");
String kategori_tipsntrick= c.getString("kategori");
HashMap<String,String> map = new HashMap<String,String>();
map.put(in_id,id);
map.put(in_pesan,pesan);
map.put(in_nama,nama_tipsntrick);
map.put(in_kategori,kategori_tipsntrick);
resultList.add(map);
}
Log.d("log", "bla:" + resultList);
}
catch (JSONException e)
{
e.printStackTrace();
}
return null;
}
下
05-05 11:06:11.299 1215-1215/com.skripsi.mazdamobil E/WindowManager﹕ Activity com.skripsi.mazdamobil.Data_Tipsntrick has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{416ef190 V.E..... R.....ID 0,0-304,96} that was originally added here
android.view.WindowLeaked: Activity com.skripsi.mazdamobil.Data_Tipsntrick has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{416ef190 V.E..... R.....ID 0,0-304,96} that was originally added here
at android.view.ViewRootImpl.<init>(ViewRootImpl.java:345)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:239)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
at android.app.Dialog.show(Dialog.java:281)
at com.skripsi.mazdamobil.Data_Tipsntrick$DownloadList.onPreExecute(Data_Tipsntrick.java:173)
at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
at android.os.AsyncTask.execute(AsyncTask.java:534)
at com.skripsi.mazdamobil.Data_Tipsntrick.onCreate(Data_Tipsntrick.java:66)
at android.app.Activity.performCreate(Activity.java:5133)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
at android.app.ActivityThread.access$600(ActivityThread.java:141)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5103)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
Data_Tipsntrick.java:173
protected void onPreExecute()
{
super.onPreExecute();
pDialog = new ProgressDialog(Data_Tipsntrick.this);
pDialog.setMessage("Tunggu Sebentar...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show(); <-- line 173
}
Data_Tipsntrick.java:66
new DownloadList().execute();
我做错了什么。原因我不太了解java JSON响应
{"result":[{"id":"7","nama":"sadasdas","kategori":"berkendara","pesan":"dasdasdasdasd"},{"id":"5","nama":"Menggati Ban Bocor","kategori":"berkendara","pesan":"asdsadasdas"}]}
答案 0 :(得分：0)
如果你得到适当的JSON响应，你可以尝试这种方式：
...
...
try {
JSONParser jParser = new JSONParser();
JSONObject json = jParser.getJSONFromUrl(url+url_param);
JSONArray result = json.getJSONArray("result");
if(result!=null) {
for (int i = 0; i < result.length(); i++) {
JSONObject c = (JSONObject) result.get(i);
String id = "", pesan = "", nama_tipsntrick = "", kategori_tipsntrick = "";
if (c.has("id"))
id = c.getString("id");
if (c.has("pesan"))
pesan = c.getString("pesan");
if (c.has("nam"))
nama_tipsntrick = c.getString("nama");
if (c.has("kategori"))
kategori_tipsntrick = c.getString("kategori");
HashMap<String, String> map = new HashMap<String, String>();
map.put(in_id, id);
map.put(in_pesan, pesan);
map.put(in_nama, nama_tipsntrick);
map.put(in_kategori, kategori_tipsntrick);
resultList.add(map);
}
}
Log.d("log", "bla:" + resultList);
} catch (JSONException e) {
e.printStackTrace();
}