android - Why am I getting null pointer exception? when adding value with static int -


please done code, when run nullpointerexception.. trying increment static int variable on button click, 5 activities. in each activity question, when answered correctly static int must increment 1. when last page reached.. display total..

package com.example.kei;  import android.os.bundle; import android.app.activity; import android.content.intent; import android.view.view; import android.view.view.onclicklistener; import android.widget.radiobutton;  public class mainactivity extends activity {       radiobutton correctchoice1;     @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main);         correctchoice1.findviewbyid(r.id.correct1);         correctchoice1.setonclicklistener(new onclicklistener() {              @override             public void onclick(view v) {                 appsingleton.score++;                 intent intent = new intent(mainactivity.this, page_two.class);                 startactivity(intent);             }         });     }      public static class appsingleton {          public static int score= 0;     }      public void choice_a(view view){         intent intent = new intent(this, page_two.class);         startactivity(intent);     }        public void choice_c(view view){         intent intent = new intent(this, page_two.class);         startactivity(intent);     }  }

in code choice_a , choice_c wrong answers. try increment correct answer onlicklistener radiobutton. why cant code execute , give null pointer exception? please help.. dont know now..

logcat:

03-25 05:21:04.811: d/dalvikvm(1052): late-enabling checkjni 03-25 05:21:04.827: e/trace(1052): error opening trace file: no such file or directory (2) 03-25 05:21:04.863: d/androidruntime(1052): shutting down vm 03-25 05:21:04.863: w/dalvikvm(1052): threadid=1: thread exiting uncaught exception (group=0xa6246288) 03-25 05:21:04.867: e/androidruntime(1052): fatal exception: main 03-25 05:21:04.867: e/androidruntime(1052): java.lang.runtimeexception: unable start activity componentinfo{com.example.kei/com.example.kei.mainactivity}: java.lang.nullpointerexception 03-25 05:21:04.867: e/androidruntime(1052):     @ android.app.activitythread.performlaunchactivity(activitythread.java:2059) 03-25 05:21:04.867: e/androidruntime(1052):     @ android.app.activitythread.handlelaunchactivity(activitythread.java:2084) 03-25 05:21:04.867: e/androidruntime(1052):     @ android.app.activitythread.access$600(activitythread.java:130) 03-25 05:21:04.867: e/androidruntime(1052):     @ android.app.activitythread$h.handlemessage(activitythread.java:1195) 03-25 05:21:04.867: e/androidruntime(1052):     @ android.os.handler.dispatchmessage(handler.java:99) 03-25 05:21:04.867: e/androidruntime(1052):     @ android.os.looper.loop(looper.java:137) 03-25 05:21:04.867: e/androidruntime(1052):     @ android.app.activitythread.main(activitythread.java:4745) 03-25 05:21:04.867: e/androidruntime(1052):     @ java.lang.reflect.method.invokenative(native method) 03-25 05:21:04.867: e/androidruntime(1052):     @ java.lang.reflect.method.invoke(method.java:511) 03-25 05:21:04.867: e/androidruntime(1052):     @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:786) 03-25 05:21:04.867: e/androidruntime(1052):     @ com.android.internal.os.zygoteinit.main(zygoteinit.java:553) 03-25 05:21:04.867: e/androidruntime(1052):     @ dalvik.system.nativestart.main(native method) 03-25 05:21:04.867: e/androidruntime(1052): caused by: java.lang.nullpointerexception 03-25 05:21:04.867: e/androidruntime(1052):     @ com.example.kei.mainactivity.oncreate(mainactivity.java:18) 03-25 05:21:04.867: e/androidruntime(1052):     @ android.app.activity.performcreate(activity.java:5008) 03-25 05:21:04.867: e/androidruntime(1052):     @ android.app.instrumentation.callactivityoncreate(instrumentation.java:1079) 03-25 05:21:04.867: e/androidruntime(1052):     @ android.app.activitythread.performlaunchactivity(activitythread.java:2023) 03-25 05:21:04.867: e/androidruntime(1052):     ... 11 more 03-25 05:33:23.686: e/trace(1694): error opening trace file: no such file or directory (2) 03-25 05:33:23.718: d/androidruntime(1694): shutting down vm 03-25 05:33:23.718: w/dalvikvm(1694): threadid=1: thread exiting uncaught exception (group=0xa6246288) 03-25 05:33:23.722: e/androidruntime(1694): fatal exception: main 03-25 05:33:23.722: e/androidruntime(1694): java.lang.runtimeexception: unable start activity componentinfo{com.example.kei/com.example.kei.mainactivity}: java.lang.nullpointerexception 03-25 05:33:23.722: e/androidruntime(1694):     @ android.app.activitythread.performlaunchactivity(activitythread.java:2059) 03-25 05:33:23.722: e/androidruntime(1694):     @ android.app.activitythread.handlelaunchactivity(activitythread.java:2084) 03-25 05:33:23.722: e/androidruntime(1694):     @ android.app.activitythread.access$600(activitythread.java:130) 03-25 05:33:23.722: e/androidruntime(1694):     @ android.app.activitythread$h.handlemessage(activitythread.java:1195) 03-25 05:33:23.722: e/androidruntime(1694):     @ android.os.handler.dispatchmessage(handler.java:99) 03-25 05:33:23.722: e/androidruntime(1694):     @ android.os.looper.loop(looper.java:137) 03-25 05:33:23.722: e/androidruntime(1694):     @ android.app.activitythread.main(activitythread.java:4745) 03-25 05:33:23.722: e/androidruntime(1694):     @ java.lang.reflect.method.invokenative(native method) 03-25 05:33:23.722: e/androidruntime(1694):     @ java.lang.reflect.method.invoke(method.java:511) 03-25 05:33:23.722: e/androidruntime(1694):     @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:786) 03-25 05:33:23.722: e/androidruntime(1694):     @ com.android.internal.os.zygoteinit.main(zygoteinit.java:553) 03-25 05:33:23.722: e/androidruntime(1694):     @ dalvik.system.nativestart.main(native method) 03-25 05:33:23.722: e/androidruntime(1694): caused by: java.lang.nullpointerexception 03-25 05:33:23.722: e/androidruntime(1694):     @ com.example.kei.mainactivity.oncreate(mainactivity.java:23) 03-25 05:33:23.722: e/androidruntime(1694):     @ android.app.activity.performcreate(activity.java:5008) 03-25 05:33:23.722: e/androidruntime(1694):     @ android.app.instrumentation.callactivityoncreate(instrumentation.java:1079) 03-25 05:33:23.722: e/androidruntime(1694):     @ android.app.activitythread.performlaunchactivity(activitythread.java:2023) 03-25 05:33:23.722: e/androidruntime(1694):     ... 11 more

try initialize radiobutton below:

 correctchoice1= (radiobutton )findviewbyid(r.id.correct1);     correctchoice1.setonclicklistener(new onclicklistener() {          @override         public void onclick(view v) {           if(appsingleton.score <=5)             appsingleton.score++;             intent intent = new intent(mainactivity.this, page_two.class);             startactivity(intent);         }     });

Comments

Post a Comment

Popular posts from this blog

user interface - How to replace the Python logo in a Tkinter-based Python GUI app? -

is there way change default logo, python logo , appears in window's task bar? notice have replaced default tk logo used appear in application window. i using windows 7 , python 2.6 , developing gui of tkinter. you can using winico tk extension package. winico package can used add system tray icons tk programs. the following sample shows 1 way change runtime application icon. note need provide .ico file suitable sizes of icons in on command line , need use pythonw. not change taskbar icon console when running python script. test extracted winico0.6 package python\tcl\winico0.6 folder package require winico work , ran code below using pythonw winico_test.py path\to\some\ico\file.ico . import sys tkinter import * def main(argv): root = tk() root.update() root.tk.call('package','require','winico') id = root.tk.call('winico','createfrom',argv[1]) root.tk.call('winico','setwindow',root,id...
Read more

objective c - Greedy NSProgressIndicator Allocation -

i'm using bunch of nsprogressindicators @ once (32 exact) , looks when they're animating start allocating memory no one's business greedy_run http://i62.tinypic.com/15rgmso.png i've got reports app slowdown , crash after days of uptime, , looks culprit, it's hard pinpoint bugs take days appear. i comment out call start animating, memory behaves expected. result of multiple nsprogressindicators alloc'ed on same thread? or maybe sandboxing? of constant allocations coming core animation threads, don't know else going on. custom nsview progress indicator lives in @interface myview () @property (nonatomic, strong) nsimageview *imageview; @property (nonatomic, strong) nstextview *numbertxt; @property (nonatomic, strong) nsprogressindicator *progress; @end @implementation myview - (id)initwithframe:(nsrect)framerect { self = [super initwithframe:framerect]; if (self) { // image nsimage *image = [nsimage imagenamed:@"bg.png"]; c...
Read more

how to set an OCR language in Google Drive -

i need upload image google drive including ocr feature. the problem setocrlanguage method. need specify hebrew language , based on iso 639-1 codes should "heb". i'm getting response "code" : 400, "errors" : [ { "domain" : "global", "location" : "ocrlanguage", "locationtype" : "parameter", "message" : "invalid value", "reason" : "invalid" } ], any idea should code or can list of avaliable codes?
Read more