I have creted a class through which i want to get a list url's from the database. But I get this error:
03-30 15:05:35.599 3591-3591/? E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.imran.myapp, PID: 3591
java.lang.NullPointerException: Attempt to read from null array
at com.example.imran.myapp.gridgallery.onCreateView(gridgallery.java:55)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:1962)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1026)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1207)
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:738)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1572)
at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:493)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6145)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
03-30 15:05:35.599 1032-1045/? V/ApplicationPolicy: isApplicationStateBlocked userId 0 pkgname com.example.imran.myapp
03-30 15:05:35.599 1032-1045/? W/ActivityManager: Force finishing activity com.example.imran.myapp/.Home
03-30 15:05:35.609 1032-1045/? V/ApplicationPolicy: isApplicationStateBlocked userId 0 pkgname com.example.imran.myapp
03-30 15:05:35.909 1032-1032/? D/CrashAnrDetector: processName: com.example.imran.myapp
03-30 15:05:35.919 1032-1032/? D/CrashAnrDetector: broadcastEvent : com.example.imran.myapp data_app_crash
03-30 15:05:36.159 1032-1059/? W/ActivityManager: Activity pause timeout for ActivityRecord{3f2af340 u0 com.example.imran.myapp/.Home t3125 f}
03-30 15:05:37.019 1032-1521/? I/WindowState: WIN DEATH: Window{224e112b u0 com.example.imran.myapp/com.example.imran.myapp.Home}
03-30 15:05:37.079 1032-1528/? I/ActivityManager: Process com.example.imran.myapp (pid 3591)(adj 9) has died(67,606)
03-30 15:05:37.359 10199-10199/? D/AASAservice-UpdateReceiver: AASAUpdateReceiver: android.intent.action.PACKAGE_REPLACED, package = com.example.imran.myapp, uid = -1
03-30 15:05:37.379 2433-3619/? D/PkgBroadcastIntentOp: Received broadcast action=android.intent.action.PACKAGE_REPLACED and uri=com.example.imran.myapp
03-30 15:05:37.559 2433-3974/? D/k: Processing package: com.example.imran.myapp
03-30 15:05:37.559 2227-3976/? D/Compatibility: intentservice saw: Intent { act=android.intent.action.PACKAGE_REPLACED dat=package:com.example.imran.myapp flg=0x4000010 cmp=com.sec.android.app.soundalive/.compatibility.Compatibility$Receiver (has extras) } Bundle[{android.intent.extra.UID=10252, android.intent.extra.REPLACING=true, android.intent.extra.user_handle=0}]
03-30 15:05:37.589 2433-3974/? D/GassUtils: Found app info for package com.example.imran.myapp:1. Hash: 6b9333e031907d7a6a6c12cd9fdfa0d23bd13ee0f40c9617ddd005dc358321b0
03-30 15:05:37.589 2433-3974/? D/k: Found info for package com.example.imran.myapp in db.
This is the activity in which i am using the class:
gridgallery.java
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_gridgallery, null);
Myserver myserver = new Myserver();
//postStringRequest(myserver.url + "/api/albums/getalbums.php", view);
AlbumsList albumsList = new AlbumsList(myserver.url+"/api/albums/getalbums.php",getContext(),view);
albumsList.connection(); // Do connection
Toast.makeText(getContext(),albumsList.imgsurls[1],Toast.LENGTH_LONG).show();
/*
GridView gv = (GridView)view.findViewById(R.id.fragment_gridgallery);
ImageAdapter myadapter = new ImageAdapter(getContext(),albumsList.imgurls());
gv.setAdapter(myadapter);
*/
return view;
}
AlbumsList.java
public class AlbumsList {
private String server;
Context mycontext;
public String[] imgsurls;
private View view;
AlbumsList(String serverurl, Context c,View uview){
mycontext = c;
server = serverurl;
view = uview;
}
public View connection(){
// Instantiate the RequestQueue.
RequestQueue queue = Volley.newRequestQueue(mycontext);
// Request a string response from the provided URL.
StringRequest stringRequest = new StringRequest(Request.Method.POST, server,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
//GridView gv = (GridView)view.findViewById(R.id.fragment_gridgallery);
final ArrayList<String> urls2 = new ArrayList<String>();
try {
JSONArray jsonObj = new JSONArray(response);
Myserver myserver = new Myserver();
for (int i=0;i<jsonObj.length();i++){
JSONObject c = jsonObj.getJSONObject(i);
String imgurl = myserver.url+"/images/thumbs/tn_"+c.getString("album_thumbnail");
urls2.add(imgurl);
}
final String myabc[] = urls2.toArray(new String[urls2.size()]); //Do not remove this
imgsurls = myabc;
Toast.makeText(mycontext, imgsurls[0], Toast.LENGTH_LONG).show(); //Interestingly this toast works and imgsurls[] is ok
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(mycontext,e.getLocalizedMessage(),Toast.LENGTH_LONG).show();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(mycontext, "Unable to reach server", Toast.LENGTH_LONG).show();
}
}) {
#Override
protected Map<String, String> getParams() {
Map<String, String> params = new HashMap<String, String>();
params.put("getalbum", "getalbum");
return params;
}
};
queue.add(stringRequest);
return view;
}
public String[] imgurls(){
return imgsurls;
}
}
In AlbumsList.java, I want to return the list of URLS by either a function or variables, but both approachs don't work. Interestingly the url's are fetched proper from database. And that Toast inside AlbumsList.java: Toast.makeText(mycontext, imgsurls[0], Toast.LENGTH_LONG).show(); also works. Then I don't know why the imgsurls is not returned to main function. Thanks in advance.
Because Volley request is asynchronous.
Thus when are you calling albumsList.connection();, the request is running in background and before it is completed, control comes to the following line:
Toast.makeText(getContext(),albumsList.imgsurls[1],Toast.LENGTH_LONG).show();
And by that time, your request is not completed.
Volley works in an asynchronous fashion. This means that it doesn't return the result of the operation immediately. You are trying to access the results before they are fetched from the server.
You should move your view initialisation logic to the onResponse(), when the result is actually being delivered.
Related
This question already has answers here:
What is a NullPointerException, and how do I fix it?
(12 answers)
Closed 5 years ago.
I am a beginner at android studio, I have a mission to redesign the app. I use the Fragment. But when I run my app, it has stopped and there is no error in my Gradle. I looked for many website to solve my question, but still have no idea.
I have some questions below.
How can I fix the java.lang.RuntimeException (NULL Pointer Exception) ?
09-30 02:59:56.574 17706-17706/? E/memtrack: Couldn't load memtrack module (No such file or directory)
09-30 02:59:56.574 17706-17706/? E/android.os.Debug: failed to load memtrack module: -2
09-30 02:59:56.996 17722-17722/? E/memtrack: Couldn't load memtrack module (No such file or directory)
09-30 02:59:56.996 17722-17722/? E/android.os.Debug: failed to load memtrack module: -2
09-30 02:59:57.090 17734-17734/? E/AndroidRuntime: FATAL EXCEPTION: main
Process: tw.com.flag.parking22, PID: 17734
java.lang.RuntimeException: Unable to start activity ComponentInfo{tw.com.flag.parking22/tw.com.flag.parking22.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2325)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
at tw.com.flag.parking22.MainActivity.init(MainActivity.java:102)
at tw.com.flag.parking22.MainActivity.onCreate(MainActivity.java:71)
at android.app.Activity.performCreate(Activity.java:5990)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2278)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
at android.app.ActivityThread.access$800(ActivityThread.java:151)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
09-30 02:59:57.211 1160-1160/? E/EGL_emulation: tid 1160: eglCreateSyncKHR(1865): error 0x3004 (EGL_BAD_ATTRIBUTE)
09-30 03:02:15.409 2159-19872/com.google.android.gms E/Herrevad: [350] RemoteReportsRefreshChimeraService.a: want to send authenticated request, but no Google account on device
09-30 03:02:15.445 1998-2721/com.google.android.gms.persistent E/SQLiteLog: (2067) abort at 31 in [INSERT INTO pending_ops(source,tag,requires_charging,target_package,source_version,required_network_type,flex_time,target_class,runtime,retry_strategy,last_runtime,period,task_type,job_id,user_
09-30 03:02:15.445 1998-2721/com.google.android.gms.persistent E/SQLiteDatabase: Error inserting source=4 tag=NetworkReportService requires_charging=0 target_package=com.google.android.gms source_version=11509000 required_network_type=2 flex_time=3600000 target_class=com.google.android.gms.common.stats.net.NetworkReportService runtime=1506742923454 retry_strategy={"maximum_backoff_seconds":{"3600":0},"initial_backoff_seconds":{"30":0},"retry_policy":{"0":0}} last_runtime=0 period=7200000 task_type=1 job_id=-1 user_id=0
android.database.sqlite.SQLiteConstraintException: UNIQUE constraint failed: pending_ops.tag, pending_ops.target_class, pending_ops.target_package, pending_ops.user_id (code 2067)
at android.database.sqlite.SQLiteConnection.nativeExecuteForLastInsertedRowId(Native Method)
at android.database.sqlite.SQLiteConnection.executeForLastInsertedRowId(SQLiteConnection.java:782)
at android.database.sqlite.SQLiteSession.executeForLastInsertedRowId(SQLiteSession.java:788)
at android.database.sqlite.SQLiteStatement.executeInsert(SQLiteStatement.java:86)
at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1471)
at android.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1341)
at swi.a(:com.google.android.gms#11509280:208)
at sxo.a(:com.google.android.gms#11509280:64)
at sxp.handleMessage(:com.google.android.gms#11509280:29)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.os.HandlerThread.run(HandlerThread.java:61)
09-30 03:02:15.446 1998-2721/com.google.android.gms.persistent E/NetworkScheduler: Error persisting task: com.google.android.gms/.common.stats.net.NetworkReportService{u=0 tag="NetworkReportService" trigger=window{period=7200s,flex=3600s,earliest=5988s,latest=9588s} requirements=[NET_ANY] attributes=[PERSISTED,RECURRING] scheduled=2388s last_run=N/A jid=N/A status=PENDING retries=0}
09-30 03:02:15.474 1170-1578/? E/Drm: Failed to find drm plugin
09-30 03:02:15.563 2159-2680/com.google.android.gms E/Volley: [129] BasicNetwork.performRequest: Unexpected response code 307 for https://android.googleapis.com/nova/herrevad/network_quality_info
09-30 03:02:15.888 1998-2721/com.google.android.gms.persistent E/SQLiteLog: (2067) abort at 31 in [INSERT INTO pending_ops(source,tag,requires_charging,target_package,source_version,required_network_type,flex_time,target_class,runtime,retry_strategy,last_runtime,period,task_type,job_id,user_
09-30 03:02:15.888 1998-2721/com.google.android.gms.persistent E/SQLiteDatabase: Error inserting source=4 tag=AggregationTaskTag requires_charging=0 target_package=com.google.android.gms source_version=11509000 required_network_type=2 flex_time=600000 target_class=com.google.android.gms.checkin.EventLogService runtime=1506741123628 retry_strategy={"maximum_backoff_seconds":{"3600":0},"initial_backoff_seconds":{"30":0},"retry_policy":{"0":0}} last_runtime=0 period=1800000 task_type=1 job_id=-1 user_id=0
android.database.sqlite.SQLiteConstraintException: UNIQUE constraint failed: pending_ops.tag, pending_ops.target_class, pending_ops.target_package, pending_ops.user_id (code 2067)
at android.database.sqlite.SQLiteConnection.nativeExecuteForLastInsertedRowId(Native Method)
at android.database.sqlite.SQLiteConnection.executeForLastInsertedRowId(SQLiteConnection.java:782)
at android.database.sqlite.SQLiteSession.executeForLastInsertedRowId(SQLiteSession.java:788)
at android.database.sqlite.SQLiteStatement.executeInsert(SQLiteStatement.java:86)
at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1471)
at android.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1341)
at swi.a(:com.google.android.gms#11509280:208)
at sxo.a(:com.google.android.gms#11509280:64)
at sxp.handleMessage(:com.google.android.gms#11509280:29)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.os.HandlerThread.run(HandlerThread.java:61)
09-30 03:02:15.888 1998-2721/com.google.android.gms.persistent E/NetworkScheduler: Error persisting task: com.google.android.gms/.checkin.EventLogService{u=0 tag="AggregationTaskTag" trigger=window{period=1800s,flex=600s,earliest=1787s,latest=2387s} requirements=[NET_ANY] attributes=[PERSISTED,RECURRING] scheduled=587s last_run=N/A jid=N/A status=PENDING retries=0}
09-30 03:03:37.417 1170-1578/? E/audio_hw_generic: Error opening input stream format 1, channel_mask 0010, sample_rate 16000
09-30 03:30:15.406 2159-21157/com.google.android.gms E/Herrevad: [355] RemoteReportsRefreshChimeraService.a: want to send authenticated request, but no Google account on device
09-30 03:30:15.511 2159-21162/com.google.android.gms E/ZappConnFactory: Unable to bind to PlayStore
09-30 03:30:15.518 2159-21168/com.google.android.gms E/ZappLogOperation: Unable to bind to Phonesky
09-30 03:30:15.526 2159-21162/com.google.android.gms E/ZappConnFactory: Unable to bind to PlayStore
09-30 03:30:15.526 2159-21162/com.google.android.gms E/ZappConnFactory: Unable to bind to PlayStore
09-30 03:30:15.551 2159-2678/com.google.android.gms E/Volley: [127] BasicNetwork.performRequest: Unexpected response code 307 for https://android.googleapis.com/nova/herrevad/network_quality_info
09-30 03:30:15.572 1170-1578/? E/Drm: Failed to find drm plugin
09-30 03:30:22.524 2159-2159/com.google.android.gms E/ActivityThread: Service com.google.android.gms.chimera.GmsIntentOperationService has leaked ServiceConnection ctn#2f714ea6 that was originally bound here
android.app.ServiceConnectionLeaked: Service com.google.android.gms.chimera.GmsIntentOperationService has leaked ServiceConnection ctn#2f714ea6 that was originally bound here
at android.app.LoadedApk$ServiceDispatcher.<init>(LoadedApk.java:1077)
at android.app.LoadedApk.getServiceDispatcher(LoadedApk.java:971)
at android.app.ContextImpl.bindServiceCommon(ContextImpl.java:1774)
at android.app.ContextImpl.bindService(ContextImpl.java:1757)
at android.content.ContextWrapper.bindService(ContextWrapper.java:539)
at android.content.ContextWrapper.bindService(ContextWrapper.java:539)
at android.content.ContextWrapper.bindService(ContextWrapper.java:539)
at android.content.ContextWrapper.bindService(ContextWrapper.java:539)
at com.google.android.gms.chimera.container.zapp.ZappLogOperation.onHandleIntent(:com.google.android.gms#11509280:1)
at com.google.android.chimera.IntentOperation.onHandleIntent(:com.google.android.gms#11509280:2)
at bwy.run(:com.google.android.gms#11509280:10)
at bwv.run(:com.google.android.gms#11509280:14)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
at java.lang.Thread.run(Thread.java:818)
09-30 03:44:15.607 1998-2721/com.google.android.gms.persistent E/SQLiteLog: (2067) abort at 31 in [INSERT INTO pending_ops(source,tag,requires_charging,target_package,source_version,required_network_type,flex_time,target_class,runtime,retry_strategy,last_runtime,period,task_type,job_id,user_
09-30 03:44:15.607 1998-2721/com.google.android.gms.persistent E/SQLiteDatabase: Error inserting source=4 tag=AggregationTaskTag requires_charging=0 target_package=com.google.android.gms source_version=11509000 required_network_type=2 flex_time=600000 target_class=com.google.android.gms.checkin.EventLogService runtime=1506743055606 retry_strategy={"maximum_backoff_seconds":{"3600":0},"initial_backoff_seconds":{"30":0},"retry_policy":{"0":0}} last_runtime=0 period=1800000 task_type=1 job_id=-1 user_id=0
android.database.sqlite.SQLiteConstraintException: UNIQUE constraint failed: pending_ops.tag, pending_ops.target_class, pending_ops.target_package, pending_ops.user_id (code 2067)
at android.database.sqlite.SQLiteConnection.nativeExecuteForLastInsertedRowId(Native Method)
at android.database.sqlite.SQLiteConnection.executeForLastInsertedRowId(SQLiteConnection.java:782)
at android.database.sqlite.SQLiteSession.executeForLastInsertedRowId(SQLiteSession.java:788)
at android.database.sqlite.SQLiteStatement.executeInsert(SQLiteStatement.java:86)
at android.database.sqlite.SQLiteDatabase.insertWithOnConflict(SQLiteDatabase.java:1471)
at android.database.sqlite.SQLiteDatabase.insert(SQLiteDatabase.java:1341)
at swi.a(:com.google.android.gms#11509280:208)
at sxo.a(:com.google.android.gms#11509280:64)
at sxp.handleMessage(:com.google.android.gms#11509280:29)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.os.HandlerThread.run(HandlerThread.java:61)
09-30 03:44:15.607 1998-2721/com.google.android.gms.persistent E/NetworkScheduler: Error persisting task: com.google.android.gms/.checkin.EventLogService{u=0 tag="AggregationTaskTag" trigger=window{period=1800s,flex=600s,earliest=1199s,latest=1799s} requirements=[NET_ANY] attributes=[PERSISTED,RECURRING] scheduled=0s last_run=N/A jid=N/A status=PENDING retries=0}
09-30 03:44:15.637 2159-21184/com.google.android.gms E/Herrevad: [371] RemoteReportsRefreshChimeraService.a: want to send authenticated request, but no Google account on device
09-30 03:44:15.755 2159-2676/com.google.android.gms E/Volley: [126] BasicNetwork.performRequest: Unexpected response code 307 for https://android.googleapis.com/nova/herrevad/network_quality_info
09-30 03:46:13.425 1171-1171/? E/installd: eof
09-30 03:46:13.425 1171-1171/? E/installd: failed to read size
Here is the main activity code
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
viewPager =(ViewPager) findViewById(R.id.pager);
PagerAdapter padapter = new PagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(padapter);
//--------------------------------------------------------------------
init();
Action();
}
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
if(newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
}
else {
}
}
private void init(){
System.out.println("start---------------------");
textView_userIDVal = (TextView) findViewById(R.id.textView_userIDVal);
textView_parkingNoVal = (TextView) findViewById(R.id.textView_parkingNoVal);
textView_pillarNoVal = (TextView) findViewById(R.id.textView_pillarNoVal);
textView_colorVal = (TextView) findViewById(R.id.textView_colorVal);
imageView = (ImageView) findViewById(R.id.imageView);
button_space = (Button) findViewById(R.id.button_space);
button_scan = (Button) findViewById(R.id.button_scan);
button_find = (Button) findViewById(R.id.button_find);
simpleDateFormat = new SimpleDateFormat("MM/dd 'at' HH");
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD) {
userID = Build.SERIAL;
//-------------error start next----------------
textView_userIDVal.setText("User ID : " + userID);
}
if(ContextCompat.checkSelfPermission(this, android.Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.CAMERA}, 200);
}
sharedPreferences = getSharedPreferences("Data", 0);
if(sharedPreferences.contains("parkingNum") && sharedPreferences.contains("time")) {
parkingNumtmp = sharedPreferences.getString("parkingNum", "");
textView_parkingNoVal.setText("Parking No. : " + parkingNumtmp + "\t(" + sharedPreferences.getString("time", "") + ")");
}
builder = new AlertDialog.Builder(this);
builder.setCancelable(false);
builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
}
});
builder_timeout = new AlertDialog.Builder(this);
builder_timeout.setTitle("REMIND");
builder_timeout.setMessage("Do you find your car ?");
builder_timeout.setCancelable(false);
builder_timeout.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
try {
json_data = new JSONObject();
json_data.put("MT", "timeout");
json_data.put("PlaceMac", parkingNumtmp);
json_data.put("UserMac", userID);
json_write = new JSONObject();
json_write.put("Data", json_data);
json_write.put("Read", false);
isCloseScreen = false;
} catch (JSONException e) {
e.printStackTrace();
}
thread = new Thread(TCP);
thread.start();
timer_count = 0;
startFlag = false;
}
});
builder_timeout.setNegativeButton("No", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
maxTime = 10;
maxTime = maxTime / 2;
timer_count = 0;
startFlag = true;
}
});
}
private void Action(){
button_space.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
try {
json_data = new JSONObject();
json_data.put("MT", "count");
json_write = new JSONObject();
json_write.put("Data", json_data);
json_write.put("Read", true);
//System.out.println(json_write + "\n");
} catch (JSONException e) {
e.printStackTrace();
}
thread = new Thread(TCP);
thread.start();
/*builder.setTitle("INFORMATION");
builder.setMessage("All : " + "\nNow : " );
AlertDialog alertDialog = builder.create();
alertDialog.show();*/
}
});
button_scan.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, ScanActivity.class);
startActivityForResult(intent, REQUEST_CODE);
}
});
button_find.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(parkingNumtmp != null) {
try {
maxTime = 10;
json_data = new JSONObject();
json_data.put("MT", "search");
json_data.put("PlaceMac", parkingNumtmp);
json_data.put("UserMac", userID);
json_write = new JSONObject();
json_write.put("Data", json_data);
json_write.put("Read", true);
//System.out.println(json_write + "\n");
} catch (JSONException e) {
e.printStackTrace();
}
Toast.makeText(getApplicationContext(), "Don't close the screen before you find your car ! ", Toast.LENGTH_LONG).show();
thread = new Thread(TCP);
thread.start();
}
else {
builder.setTitle("WARNING");
builder.setMessage("Please scan QRcode first!");
AlertDialog alertDialog = builder.create();
alertDialog.show();
}
}
});
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if(requestCode == REQUEST_CODE && resultCode == RESULT_OK) {
if(data != null) {
final Barcode barcode = data.getParcelableExtra("barcode");
parkingNumtmp = barcode.displayValue;
Date date = new Date();
final String time = simpleDateFormat.format(date);
sharedPreferences.edit().putString("parkingNum", parkingNumtmp).putString("time", time).commit();
textView_parkingNoVal.post(new Runnable() {
#Override
public void run() {
textView_parkingNoVal.setText("Parking No. : " + parkingNumtmp + "\t(" + time +")");
}
});
}
}
}
About Fragment. Is there any setting I have to do when I receive data form sever?
I want to put the received data to TextView in the another view .
Your init() function is probably try to find views inside fragments in view pager. However, at that moment, the fragments are not inflated yet, so your views in the activity are null and trying to do operation on them gives NPE. You should use onCreateView() of Fragment classes to find those views. Then you may notify main activity via callback mechanism.
For example, create FirstFragment as follows:
public class FirstFragment extends Fragment {
private OnFirstFragmentReadyListener callback;
#Override
public void onAttach(Context context) {
super.onAttach(context);
// This makes sure that the container activity has implemented the callback.
try {
callback = (OnFirstFragmentReadyListener) context;
} catch (ClassCastException e) {
throw new ClassCastException(context.toString()
+ " must implement OnFirstFragmentReadyListener");
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_first, container, false);
return rootView;
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
// Notify the parent activity that the fragment is inflated.
callback.onFirstFragmentReady();
}
public interface OnFirstFragmentReadyListener {
void onFirstFragmentReady();
}
}
Let the layout of FirstFragment as follows (referenced above as fragment_first):
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="#+id/first_label"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</RelativeLayout>
Assume we created two more similar fragment classes named as SecondFragment and ThirdFragment. Then the activity should be like this:
public class MainActivity extends AppCompatActivity implements FirstFragment.OnFirstFragmentReadyListener,
SecondFragment.OnSecondFragmentReadyListener, ThirdFragment.OnThirdFragmentReadyListener {
...
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
viewPager =(ViewPager) findViewById(R.id.pager);
PagerAdapter pagerAdapter = new PagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(pagerAdapter);
// Don't call these functions here, spread them into callbacks.
// init();
// Action();
}
#Override
public void onFirstFragmentReady() {
TextView firstTextView = (TextView) findViewById(R.id.first_label);
...
// Now you have the views from FirstFragment instance.
// You can now call setText() or setOnClickListener() here.
}
#Override
public void onSecondFragmentReady() {
TextView secondTextView = (TextView) findViewById(R.id.second_label);
...
// Now you have the views from SecondFragment instance.
// You can now call setText() or setOnClickListener() here.
}
#Override
public void onThirdFragmentReady() {
TextView thirdTextView = (TextView) findViewById(R.id.third_label);
...
// Now you have the views from ThirdFragment instance.
// You can now call setText() or setOnClickListener() here.
}
}
Although this code works, this may not be the best way. I think it is better to do operations on views like setting texts or assigning OnClickListeners in fragments itself. If you need to notify a fragment after an action happened in the parent activity, you can implement public methods inside fragments and you can call them from the parent activity when needed.
In fragment you should call the function in onCreateView function(reason as mention by #Mehmed) which is something like below:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.your_fragment, container, false);
//all findViewById;
TextView yourTextView = (Text)view.findViewById(R.id.yourTextView);
//here call for your function
init();
// any other function goes here
return view;
}
I'm trying to implement a system service on Android with inter-process communication based on binding a messenger. For this I'm following this tutorial:
http://www.survivingwithandroid.com/2014/01/android-bound-service-ipc-with-messenger.html
But no matter what I'm trying, i can't get it to work.
I found different tutorials online but in the end they are all based on the same procedure.
The app will crash right away when I'm trying to communicate with the service.
Error message
10-09 15:40:33.490 3468-3468/com.example.stenosis.testservice E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.stenosis.testservice, PID: 3468
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.stenosis.testservice/com.example.stenosis.testservice.MyActivity}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.example.stenosis.testservice.MyActivity.sendMsg(MyActivity.java:87)
at com.example.stenosis.testservice.MyActivity.onCreate(MyActivity.java:49)
at android.app.Activity.performCreate(Activity.java:5231)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
MyActivity.java:
public class MyActivity extends Activity {
private ServiceConnection sConn;
private Messenger messenger;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my);
// Service Connection to handle system callbacks
sConn = new ServiceConnection() {
#Override
public void onServiceDisconnected(ComponentName name) {
messenger = null;
}
#Override
public void onServiceConnected(ComponentName name, IBinder service) {
// We are conntected to the service
messenger = new Messenger(service);
}
};
// We bind to the service
bindService(new Intent(this, MyService.class), sConn, Context.BIND_AUTO_CREATE);
// Try to send a message to the service
sendMsg();
}
// This class handles the Service response
class ResponseHandler extends Handler {
#Override
public void handleMessage(Message msg) {
int respCode = msg.what;
String result = "";
switch (respCode) {
case MyService.TO_UPPER_CASE_RESPONSE: {
result = msg.getData().getString("respData");
System.out.println("result");
Toast.makeText(getApplicationContext(), result, Toast.LENGTH_LONG).show();
}
}
}
}
public void sendMsg() {
String val = "This is a test";
Message msg = Message
.obtain(null, MyService.TO_UPPER_CASE);
msg.replyTo = new Messenger(new ResponseHandler());
// We pass the value
Bundle b = new Bundle();
b.putString("data", val);
msg.setData(b);
try {
messenger.send(msg);
} catch (RemoteException e) {
e.printStackTrace();
}
}
}
MyService.java
public class MyService extends Service {
public static final int TO_UPPER_CASE = 0;
public static final int TO_UPPER_CASE_RESPONSE = 1;
private Messenger msg = new Messenger(new ConvertHanlder());;
#Override
public IBinder onBind(Intent intent) {
return msg.getBinder();
}
class ConvertHanlder extends Handler {
#Override
public void handleMessage(Message msg) {
// This is the action
int msgType = msg.what;
switch (msgType) {
case TO_UPPER_CASE: {
try {
// Incoming data
String data = msg.getData().getString("data");
Message resp = Message.obtain(null, TO_UPPER_CASE_RESPONSE);
Bundle bResp = new Bundle();
bResp.putString("respData", data.toUpperCase());
resp.setData(bResp);
msg.replyTo.send(resp);
} catch (RemoteException e) {
e.printStackTrace();
}
break;
}
default:
super.handleMessage(msg);
}
}
}
}
AndroidManifest.xml
<service android:name=".MyService" android:process=":convertprc"/>
Your problem is that the messanger property is null. You are experiencing concurrency problem. The bindService method is asynchronous - it returns immediately and performs the binding in a background thread. When the binding is done, the onServiceConnected method is invoked. When you try to send the message, the messanger is still not initialized because the onServiceConnected method is hasn't been executed yet.
I would like to update my Listview in a fragmen in a onPostExecute() separate class.
The first initialization of the the Listview doas work, but wehe I call createList() again, the App crashes (NullPointerException)
Any Idea?
Main_Fragment:
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
View fragmentView = inflater.inflate(R.layout.main_fragment, container, false);
StartSocketService = (Button) fragmentView.findViewById(R.id.start_socketservice);
StartSocketService.setOnClickListener(this);
StopSocketService = (Button) fragmentView.findViewById(R.id.stop_socketservice);
StopSocketService.setOnClickListener(this);
listview = (ListView) fragmentView.findViewById(R.id.listView1);
createList();
return fragmentView;
}
public void createList(){
//Reading Server IPs from SharedPreferences and put them to ListView
SharedPreferences settings = getActivity().getSharedPreferences("Found_Devices", 0);
for (int i = 0; i < 255; i++) {
if ((settings.getString("Server"+i,null)) != null) {
serverList.add(settings.getString("Server"+i, null));
Log.v("Reading IP: " +settings.getString("Server"+i, null), " from SraredPreferrences at pos.: "+i );
}
}
//Initializing listView
final StableArrayAdapter adapter = new StableArrayAdapter(getActivity(),android.R.layout.simple_list_item_1, serverList);
listview.setAdapter(adapter);
listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#TargetApi(Build.VERSION_CODES.JELLY_BEAN)
#Override
public void onItemClick(AdapterView<?> parent, final View view, int position, long id) {
final String item = (String) parent.getItemAtPosition(position);
view.animate().setDuration(2000).alpha(0).withEndAction(new Runnable() {
#Override
public void run() {
serverList.remove(item);
adapter.notifyDataSetChanged();
view.setAlpha(1);
}
});
}
});
}
Some class:
async_cient = new AsyncTask<Void, Void, Void>() {
...
protected void onPostExecute(Void result) {
Toast.makeText(mContext, "Scan Finished", Toast.LENGTH_SHORT).show();
Main_Fragment cList = new Main_Fragment();
cList.createList();
super.onPostExecute(result);
}
};
Log:
07-29 14:42:46.428 3382-3382/de.liquidbeam.LED.control D/AndroidRuntime﹕ Shutting down VM
07-29 14:42:46.428 3382-3382/de.liquidbeam.LED.control W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x41549ba8)
07-29 14:42:46.438 3382-3382/de.liquidbeam.LED.control E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: de.liquidbeam.LED.control, PID: 3382
java.lang.NullPointerException
at de.liquidbeam.LED.control.fragments.Main_Fragment.createList(Main_Fragment.java:56)
at de.liquidbeam.LED.control.background.UDP_Discover$1.onPostExecute(UDP_Discover.java:94)
at de.liquidbeam.LED.control.background.UDP_Discover$1.onPostExecute(UDP_Discover.java:57)
at android.os.AsyncTask.finish(AsyncTask.java:632)
at android.os.AsyncTask.access$600(AsyncTask.java:177)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:645)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at dalvik.system.NativeStart.main(Native Method)
07-29 14:47:46.591 3382-3382/de.liquidbeam.LED.control I/Process﹕ Sending signal. PID: 3382 SIG: 9
Lines:
56 : SharedPreferences settings = getActivity().getSharedPreferences("Found_Devices", 0);
94 : cList.createList();
57: async_cient = new AsyncTask<Void, Void, Void>() {
You creating a new instance of your fragment with no context (activity) to run in. So
the line
SharedPreferences settings = getActivity().getSharedPreferences("Found_Devices", 0);
Tries to get his activity but there is no activity where the fragment lives in ;)
What I'm trying do to is using a custom CursorAdapter, in order to choose which layout to show and also to populate View items such as TextViews and also ImageView.
Now not in all the listview items there gonna be an image.
My CursorAdapter code is -
private static class ViewHolder {
TextView mesg;
TextView mesg2;
TextView send;
ImageView myImage;
}
public class ChatCursorAdapter extends CursorAdapter implements OnClickListener {
public ChatCursorAdapter(Context context, Cursor c) {
super(context, c, 0);
}
#Override
public int getCount() {
return getCursor() == null ? 0 : super.getCount();
}
#Override
public int getViewTypeCount() {
return 2;
}
#Override
public int getItemViewType(int _position) {
Cursor cursor = (Cursor) getItem(_position);
return getItemViewType(cursor);
}
private int getItemViewType(Cursor cursor) {
String sender = cursor.getString(2);
String saveUser = user;
if (saveUser.equalsIgnoreCase(sender)){
return 0;
}else{
return 1;
}
}
#Override
public void bindView(View view, Context context, Cursor cursor) {
ViewHolder holder = (ViewHolder) view.getTag();
String msg = cursor.getString(3);
String msg2 = cursor.getString(4);
String sender = cursor.getString(2);
holder.mesg.setText(getSmiledText(Main.this,msg));
holder.mesg2.setText(getSmiledText(Main.this,msg2));
holder.send.setText(sender);
picPath = cursor.getString(8);
if(picPath == null || picPath.isEmpty()){
holder.myImage.setVisibility(View.GONE);
}else{
File file = new File(picPath);
if(file.exists()){
new AsyncImageSetter(holder.myImage, picPath).execute();
holder.myImage.setOnClickListener(this);
}
}
#Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
ViewHolder holder = new ViewHolder();
View itemLayout = null;
switch(getItemViewType(cursor)){
case 0:
itemLayout = getLayoutInflater().inflate(R.layout.msg_item1,parent, false);
break;
case 1:
itemLayout = getLayoutInflater().inflate(R.layout.msg_item13, parent,false);
break;
}
itemLayout.setTag(holder);
holder.mesg = (TextView) itemLayout.findViewById(R.id.text_start);
holder.mesg2 = (TextView) itemLayout.findViewById(R.id.text_end);
holder.send = (TextView) itemLayout.findViewById(R.id.text_from);
holder.myImage = (ImageView) itemLayout.findViewById(R.id.imageView_msgpic);
return itemLayout;
}
}
As you can see when there a need to load an image to the ImageView, I'm using asynctask in order to let the flow of the list view scrolling to be much more smoother.
This how the asynctask code is -
public class AsyncImageSetter extends AsyncTask<Void, Void, Void> {
private ImageView img;
private String path;
private Bitmap bm;
public AsyncImageSetter(ImageView img, String path) {
this.img = img;
this.path = path;
}
#Override
protected Void doInBackground(Void... params) {
bm = BitmapFactory.decodeFile(path);
bm = setImageToImageView(path);
return null;
}
#Override
protected void onPostExecute(Void result) {
img.setTag(path);
img.setImageBitmap(bm);
//img.setVisibility(View.VISIBLE);
super.onPostExecute(result);
}
}
Well the thing is that it sure made the scrolling alot more smoother, but it seems to make the app crash a lot of times.
The logcat says the next -
03-24 17:07:34.125: E/AndroidRuntime(15422): FATAL EXCEPTION: AsyncTask #2
03-24 17:07:34.125: E/AndroidRuntime(15422): java.lang.RuntimeException: An error occured while executing doInBackground()
03-24 17:07:34.125: E/AndroidRuntime(15422): at android.os.AsyncTask$3.done(AsyncTask.java:299)
03-24 17:07:34.125: E/AndroidRuntime(15422): at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
03-24 17:07:34.125: E/AndroidRuntime(15422): at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
03-24 17:07:34.125: E/AndroidRuntime(15422): at java.util.concurrent.FutureTask.run(FutureTask.java:239)
03-24 17:07:34.125: E/AndroidRuntime(15422): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
03-24 17:07:34.125: E/AndroidRuntime(15422): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
03-24 17:07:34.125: E/AndroidRuntime(15422): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
03-24 17:07:34.125: E/AndroidRuntime(15422): at java.lang.Thread.run(Thread.java:841)
03-24 17:07:34.125: E/AndroidRuntime(15422): Caused by: java.lang.OutOfMemoryError
03-24 17:07:34.125: E/AndroidRuntime(15422): at android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
03-24 17:07:34.125: E/AndroidRuntime(15422): at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:623)
03-24 17:07:34.125: E/AndroidRuntime(15422): at android.graphics.BitmapFactory.decodeFile(BitmapFactory.java:378)
03-24 17:07:34.125: E/AndroidRuntime(15422): at android.graphics.BitmapFactory.decodeFile(BitmapFactory.java:417)
03-24 17:07:34.125: E/AndroidRuntime(15422): at at.vcity.androidim.MainChat$AsyncImageSetter.doInBackground(MainChat.java:3356)
03-24 17:07:34.125: E/AndroidRuntime(15422): at at.vcity.androidim.MainChat$AsyncImageSetter.doInBackground(MainChat.java:1)
03-24 17:07:34.125: E/AndroidRuntime(15422): at android.os.AsyncTask$2.call(AsyncTask.java:287)
03-24 17:07:34.125: E/AndroidRuntime(15422): at java.util.concurrent.FutureTask.run(FutureTask.java:234)
03-24 17:07:34.125: E/AndroidRuntime(15422): ... 4 more
So what am I doing wrong here?
Thanks for any kind of help
It looks to me like the Bitmap you are trying to store in memory is too large to be stored in your tablet/emulator's memory. Here;
bm = BitmapFactory.decodeFile(path);
See if the code works with a much smaller file than the one that is coming from your current path (also see if it works with a smaller list). This could also be an instance of 'The straw that broke the camel's back'. If your current application is already very memory intensive you might have to go through your current code and optimise for memory management.
Because your are creating an AsyncTask for each item in the ListView, your trying to hold that many images in memory at once. So you might need to find another way to do it. You might need to try loading the image's thumbnail into your ImageViews instead.
An example of getting an images thumbnail.
I hope this helps.
An Example Implementation
Just to run through a potential way to implement the above linked thumbnail example, what I might do to get the thumbnail is I could store the context passed to your ChatCursorAdapter by adding the following as a class variable (and instantiate it in the constructor);
Context ourContext;
public ChatCursorAdapter(Context context, Cursor c) {
super(context, c, 0);
ourContext = context;
}
#Override
public void bindView(View view, Context context, Cursor cursor) {
...
new AsyncImageSetter(holder.myImage, picPath, ourContext.getContentResolver()).execute();
...
}
Then (as above) I might use the Context to get the ContentResolver instance and pass that instance into your AsyncTask via it's constructor. Then we could add the method in the example code to get the thumbnail into the custom AsyncTask, which might look something like this;
ContentResolver cr;
public AsyncImageSetter(ImageView img, String path, ContentResolver cr) {
this.img = img;
this.path = path;
this.cr = cr;
}
...
#Override
protected Void doInBackground(Void... params) {
try{
bm = getThumbnail(cr, path);
}catch(Exception e){}
return null;
}
private Bitmap getThumbnail(ContentResolver cr, String path) throws Exception {
Cursor ca = cr.query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, new String[] { MediaStore.MediaColumns._ID }, MediaStore.MediaColumns.DATA + "=?", new String[] {path}, null);
if (ca != null && ca.moveToFirst()) {
int id = ca.getInt(ca.getColumnIndex(MediaStore.MediaColumns._ID));
ca.close();
return MediaStore.Images.Thumbnails.getThumbnail(cr, id, MediaStore.Images.Thumbnails.MICRO_KIND, null );
}
ca.close();
return null;
}
The cause is in your stacktrace: java.lang.OutOfMemoryError. It looks like one of two things -- either your images are too large or you are leaking memory (or both).
My recommendation would be to use one of the several libraries for doing background image loading. Here are a couple of suggestions:
https://github.com/nostra13/Android-Universal-Image-Loader
https://github.com/square/picasso
Hey guys can you look at my errors, my logcat says it is because i am getting null pointer exception. i don't understand why. I just added a String variable which is "Email" and make the value of my eadd which stands for email address equals to it, then i have these errors now. can you point to me the problem guys?
These are my codes:
**
public class LoginSub extends Activity {
public static String Email;
// Progress Dialog
private ProgressDialog pDialog;
JSONParser jsonParser = new JSONParser();
EditText inputEmail;
EditText inputPassword;
TextView TextView1;
// url to create new product
//private static String url_create_product = "http://student-thesis.netii.net/log_in.php";
private static String url_create_product = "http://10.0.2.2/TheCalling/log_in.php";
// JSON Node names
private static final String TAG_SUCCESS = "success";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Edit Text
inputEmail = (EditText) findViewById(R.id.inputEmail);
inputPassword = (EditText) findViewById(R.id.inputPassword);
// Create button
Button btnLogin = (Button) findViewById(R.id.btnLogin);
// button click event
btnLogin.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// creating new product in background thread
new phpconnect().execute();
}
});
Button btnReg = (Button) findViewById(R.id.btnReg);
// button click event
btnReg.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent i = new Intent(getApplicationContext(), Register.class);
startActivity(i);
}
});
}
/**
* Background Async Task to Create new product
* */
class phpconnect extends AsyncTask<String, String, String> {
/**
* Before starting background thread Show Progress Dialog
* */
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(LoginSub.this);
pDialog.setMessage("Logging in..");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
/**
* Creating product
* */
protected String doInBackground(String... args) {
String eadd = inputEmail.getText().toString();
String password = inputPassword.getText().toString();
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("eadd", eadd));
params.add(new BasicNameValuePair("password", password));
// getting JSON Object
// Note that create product url accepts POST method
JSONObject json = jsonParser.makeHttpRequest(url_create_product,
"POST", params);
// check log cat fro response
Log.d("Create Response", json.toString());
// check for success tag
try {
int success = json.getInt(TAG_SUCCESS);
Email.equals(eadd);
if (success == 1) {
// successfully created product
Intent i = new Intent(getApplicationContext(), Mapping.class);
startActivity(i);
// closing this screen
finish();
} else {
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog once done
pDialog.dismiss();
}
}
}
**
and here's my logcat errors:
**
03-06 22:21:16.428: E/AndroidRuntime(1417): FATAL EXCEPTION: AsyncTask #1
03-06 22:21:16.428: E/AndroidRuntime(1417): java.lang.RuntimeException: An error occured while executing doInBackground()
03-06 22:21:16.428: E/AndroidRuntime(1417): at android.os.AsyncTask$3.done(AsyncTask.java:278)
03-06 22:21:16.428: E/AndroidRuntime(1417): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
03-06 22:21:16.428: E/AndroidRuntime(1417): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
03-06 22:21:16.428: E/AndroidRuntime(1417): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
03-06 22:21:16.428: E/AndroidRuntime(1417): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
03-06 22:21:16.428: E/AndroidRuntime(1417): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
03-06 22:21:16.428: E/AndroidRuntime(1417): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
03-06 22:21:16.428: E/AndroidRuntime(1417): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
03-06 22:21:16.428: E/AndroidRuntime(1417): at java.lang.Thread.run(Thread.java:856)
03-06 22:21:16.428: E/AndroidRuntime(1417): Caused by: java.lang.NullPointerException
03-06 22:21:16.428: E/AndroidRuntime(1417): at com.example.projectthesis.LoginSub$phpconnect.doInBackground(LoginSub.java:129)
03-06 22:21:16.428: E/AndroidRuntime(1417): at com.example.projectthesis.LoginSub$phpconnect.doInBackground(LoginSub.java:1)
03-06 22:21:16.428: E/AndroidRuntime(1417): at android.os.AsyncTask$2.call(AsyncTask.java:264)
03-06 22:21:16.428: E/AndroidRuntime(1417): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
**
Thank you guys.
Remove this block from doInBackGround()
if (success == 1) {
// successfully created product
Intent i = new Intent(LoginSub.this, Mapping.class);
startActivity(i);
// closing this screen
finish();
} else {
}
And add it in onPostExecute() section
protected void onPostExecute(String file_url)
{
// dismiss the dialog once done
pDialog.dismiss();
if (success == 1)
{
// successfully created product
Intent i = new Intent(getApplicationContext(), Mapping.class);
startActivity(i);
// closing this screen
finish();
}
else
{
}
}
Some times getApplicationContext() wont provide the exact context values. So pass the
Context context; //declare
context=this;// assigning next line after setcontextview.
then pass the context instead of getApplicationContext() . and check it and also if you want to do any UI updates you are not supposed to do in doinBackground(). You have to do in post execute.
Hope this will help you.
I think because this line
new phpconnect().execute();
and
class phpconnect extends AsyncTask<String, String, String> {
You declare AsyncTask with <String, String, String> but you didn't pass any parameter in .exeute();
Moreover that, from your code you don't want any parameter for AsyncTask so you should declare your Asynctask like this
class phpconnect extends AsyncTask<Void, Void, Void> {