Android应用程序崩溃数据库

Question

Me and my friend are trying to develop an app where it interacts with the database, basically adding deleting the items from the cart. We have a problem with the database connection with the app, I guess.

For now, we are actually using the following tutorial to develop the app with php and mysql: http://www.androidhive.info/2012/05/how-to-connect-android-with-php-mysql/

I am hosting the files from the 000webhost.com with the php files on it and a database named "Products" to send the data to from the app.

Everything we did, is same as explained in the tutorial, but instead of the url within the application for the php files, I've mentioned my domainname from the 000webhost.com where the files are resided. But, the app crashes and exits. Tried several urls and even from the localhost (XAMP), we still clueless.

I am thankful in advance for any suggestions and solutions to this issue!

Thank you!

Below is the logcat I got from the Eclipse after running the application:

    11-03 18:21:25.790: E/JSON Parser(917): Error parsing data org.json.JSONException: Value <br><table of type java.lang.String cannot be converted to JSONObject
11-03 18:21:25.950: E/AndroidRuntime(917): FATAL EXCEPTION: AsyncTask #1
11-03 18:21:25.950: E/AndroidRuntime(917): Process: com.example.database, PID: 917
11-03 18:21:25.950: E/AndroidRuntime(917): java.lang.RuntimeException: An error occured while executing doInBackground()
11-03 18:21:25.950: E/AndroidRuntime(917):  at android.os.AsyncTask$3.done(AsyncTask.java:300)
11-03 18:21:25.950: E/AndroidRuntime(917):  at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:355)
11-03 18:21:25.950: E/AndroidRuntime(917):  at java.util.concurrent.FutureTask.setException(FutureTask.java:222)
11-03 18:21:25.950: E/AndroidRuntime(917):  at java.util.concurrent.FutureTask.run(FutureTask.java:242)
11-03 18:21:25.950: E/AndroidRuntime(917):  at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
11-03 18:21:25.950: E/AndroidRuntime(917):  at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
11-03 18:21:25.950: E/AndroidRuntime(917):  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
11-03 18:21:25.950: E/AndroidRuntime(917):  at java.lang.Thread.run(Thread.java:841)
11-03 18:21:25.950: E/AndroidRuntime(917): Caused by: java.lang.NullPointerException
11-03 18:21:25.950: E/AndroidRuntime(917):  at com.example.database.AllProductsActivity$LoadAllProducts.doInBackground(AllProductsActivity.java:130)
11-03 18:21:25.950: E/AndroidRuntime(917):  at com.example.database.AllProductsActivity$LoadAllProducts.doInBackground(AllProductsActivity.java:1)
11-03 18:21:25.950: E/AndroidRuntime(917):  at android.os.AsyncTask$2.call(AsyncTask.java:288)
11-03 18:21:25.950: E/AndroidRuntime(917):  at java.util.concurrent.FutureTask.run(FutureTask.java:237)
11-03 18:21:25.950: E/AndroidRuntime(917):  ... 4 more
11-03 18:21:31.810: E/WindowManager(917): android.view.WindowLeaked: Activity com.example.database.AllProductsActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView{b4de64a0 V.E..... R.....ID 0,0-383,96} that was originally added here
11-03 18:21:31.810: E/WindowManager(917):   at android.view.ViewRootImpl.<init>(ViewRootImpl.java:348)
11-03 18:21:31.810: E/WindowManager(917):   at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:248)
11-03 18:21:31.810: E/WindowManager(917):   at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:69)
11-03 18:21:31.810: E/WindowManager(917):   at android.app.Dialog.show(Dialog.java:286)
11-03 18:21:31.810: E/WindowManager(917):   at com.example.database.AllProductsActivity$LoadAllProducts.onPreExecute(AllProductsActivity.java:117)
11-03 18:21:31.810: E/WindowManager(917):   at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:587)
11-03 18:21:31.810: E/WindowManager(917):   at android.os.AsyncTask.execute(AsyncTask.java:535)
11-03 18:21:31.810: E/WindowManager(917):   at com.example.database.AllProductsActivity.onCreate(AllProductsActivity.java:57)
11-03 18:21:31.810: E/WindowManager(917):   at android.app.Activity.performCreate(Activity.java:5231)
11-03 18:21:31.810: E/WindowManager(917):   at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
11-03 18:21:31.810: E/WindowManager(917):   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
11-03 18:21:31.810: E/WindowManager(917):   at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
11-03 18:21:31.810: E/WindowManager(917):   at android.app.ActivityThread.access$800(ActivityThread.java:135)
11-03 18:21:31.810: E/WindowManager(917):   at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
11-03 18:21:31.810: E/WindowManager(917):   at android.os.Handler.dispatchMessage(Handler.java:102)
11-03 18:21:31.810: E/WindowManager(917):   at android.os.Looper.loop(Looper.java:136)
11-03 18:21:31.810: E/WindowManager(917):   at android.app.ActivityThread.main(ActivityThread.java:5017)
11-03 18:21:31.810: E/WindowManager(917):   at java.lang.reflect.Method.invokeNative(Native Method)
11-03 18:21:31.810: E/WindowManager(917):   at java.lang.reflect.Method.invoke(Method.java:515)
11-03 18:21:31.810: E/WindowManager(917):   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
11-03 18:21:31.810: E/WindowManager(917):   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
11-03 18:21:31.810: E/WindowManager(917):   at dalvik.system.NativeStart.main(Native Method)

Answer 1

you have problem with your web API response

see the error log says

>  11-03 18:21:25.790: E/JSON Parser(917): Error parsing data
> org.json.JSONException: Value <br><table of type java.lang.String
> cannot be converted to JSONObject

now since you are not getting a proper JSON from the URL, JSONObject json is getting null and then the code furthur goes down and throws null pointer exception mostly in (as per the sample code in the url you have given)

int success = json.getInt(TAG_SUCCESS);

log corresponding to it gives the line number as well. you can double check it in your code(AllProductsActivity.java line num 130)

11-03 18:21:25.950: E/AndroidRuntime(917): Caused by: java.lang.NullPointerException 11-03 18:21:25.950: E/AndroidRuntime(917): at com.example.database.AllProductsActivity$LoadAllProducts.doInBackground(AllProductsActivity.java:130)