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POHow do I make it wait until a function has returned? Android
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  1. POHow do I make it wait until a function has returned? Android
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    copied!<p>Sorry to just dump code, but I'm trying to make a menu. When you start the program, It just says "Unfortunately, ScoutingDraft had stopped working." I can't figure out the problem.</p> <pre><code>package cody.graham.scoutingdraft; import...; public class MyMenu extends ListActivity{ String UserName="a"; String display[] = {"Welcome" ,"Login" ,"Exit" }; String classes[] = {"return()","login()","finish()"}; EditText user=(EditText) findViewById(R.id.ETUserInput); Button login=(Button) findViewById(R.id.BLogin),logout=(Button) findViewById(R.id.BLogout); TextView errmsg=(TextView) findViewById(R.id.TVErrorReport); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setListAdapter(new ArrayAdapter&lt;String&gt;(MyMenu.this,android.R.layout.simple_list_item_1,display)); } @Override public void onBackPressed(){finish();} @Override protected void onListItemClick(ListView l, View v, int position,long id) { super.onListItemClick(l, v, position, id); if (classes[position].equals("return()")){return;} if (classes[position].equals("finish()")){finish();return;} if (classes[position].equals("login()")){ final Dialog logd=new Dialog(this); logd.setContentView(R.layout.login_dialog); logd.setCancelable(false); login.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { int len=user.getText().toString().length(); if (len&lt;3){errmsg.setText("Too short"); return;} if (len&gt;10){errmsg.setText("Too long"); return;} UserName=user.getText().toString(); display[1]="Welcome, "+UserName; display[2]="Logout"; logd.dismiss(); } }); logout.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { UserName="a"; display[1]="Welcome"; display[2]="Login"; logd.dismiss(); } }); logd.show(); return; } try{ Class&lt;?&gt; cvar=Class.forName("cody.graham.scoutingdraft."+classes[position]); Intent intention=new Intent(MyMenu.this,cvar); startActivity(intention); }catch(ClassNotFoundException e){ e.printStackTrace(); } } public String getUser(){ return UserName; } public void setUser(String newuser){ UserName=newuser; } } </code></pre> <p>I don't have any other java files yet(This is the whole program so far) but the only options I give it should trigger one of the 3 if statements and return before trying to create the class. Even if this weren't true, it shouldn't crash until I click something.</p> <p>LogCat:</p> <pre><code>11-12 17:24:45.925: I/ActivityManager(165): START {act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10200000 cmp=cody.graham.scoutingdraft/.MyMenu bnds=[0,405][120,555] u=0} from pid 263 11-12 17:24:45.956: W/WindowManager(165): Failure taking screenshot for (246x410) to layer 21005 11-12 17:24:45.975: E/PowerManagerService(165): Excessive delay setting brightness: 140ms, mask=2 11-12 17:24:46.137: D/dalvikvm(6708): Not late-enabling CheckJNI (already on) 11-12 17:24:46.155: I/ActivityManager(165): Start proc cody.graham.scoutingdraft for activity cody.graham.scoutingdraft/.MyMenu: pid=6708 uid=10047 gids={1028} 11-12 17:24:46.235: E/PowerManagerService(165): Excessive delay setting brightness: 259ms, mask=2 11-12 17:24:46.525: E/PowerManagerService(165): Excessive delay setting brightness: 266ms, mask=2 11-12 17:24:46.606: I/Choreographer(165): Skipped 31 frames! The application may be doing too much work on its main thread. 11-12 17:24:46.708: E/PowerManagerService(165): Excessive delay setting brightness: 176ms, mask=2 11-12 17:24:47.005: E/PowerManagerService(165): Excessive delay setting brightness: 284ms, mask=2 11-12 17:24:47.146: E/Trace(6708): error opening trace file: No such file or directory (2) 11-12 17:24:47.656: D/AndroidRuntime(6708): Shutting down VM 11-12 17:24:47.656: W/dalvikvm(6708): threadid=1: thread exiting with uncaught exception (group=0x40a13300) 11-12 17:24:47.686: E/AndroidRuntime(6708): FATAL EXCEPTION: main 11-12 17:24:47.686: E/AndroidRuntime(6708): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{cody.graham.scoutingdraft/cody.graham.scoutingdraft.MyMenu}: java.lang.NullPointerException 11-12 17:24:47.686: E/AndroidRuntime(6708): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983) 11-12 17:24:47.686: E/AndroidRuntime(6708): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084) 11-12 17:24:47.686: E/AndroidRuntime(6708): at android.app.ActivityThread.access$600(ActivityThread.java:130) 11-12 17:24:47.686: E/AndroidRuntime(6708): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195) 11-12 17:24:47.686: E/AndroidRuntime(6708): at android.os.Handler.dispatchMessage(Handler.java:99) 11-12 17:24:47.686: E/AndroidRuntime(6708): at android.os.Looper.loop(Looper.java:137) 11-12 17:24:47.686: E/AndroidRuntime(6708): at android.app.ActivityThread.main(ActivityThread.java:4745) 11-12 17:24:47.686: E/AndroidRuntime(6708): at java.lang.reflect.Method.invokeNative(Native Method) 11-12 17:24:47.686: E/AndroidRuntime(6708): at java.lang.reflect.Method.invoke(Method.java:511) 11-12 17:24:47.686: E/AndroidRuntime(6708): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) 11-12 17:24:47.686: E/AndroidRuntime(6708): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 11-12 17:24:47.686: E/AndroidRuntime(6708): at dalvik.system.NativeStart.main(Native Method) 11-12 17:24:47.686: E/AndroidRuntime(6708): Caused by: java.lang.NullPointerException 11-12 17:24:47.686: E/AndroidRuntime(6708): at android.app.Activity.findViewById(Activity.java:1825) 11-12 17:24:47.686: E/AndroidRuntime(6708): at cody.graham.scoutingdraft.MyMenu.&lt;init&gt;(MyMenu.java:18) 11-12 17:24:47.686: E/AndroidRuntime(6708): at java.lang.Class.newInstanceImpl(Native Method) 11-12 17:24:47.686: E/AndroidRuntime(6708): at java.lang.Class.newInstance(Class.java:1319) 11-12 17:24:47.686: E/AndroidRuntime(6708): at android.app.Instrumentation.newActivity(Instrumentation.java:1053) 11-12 17:24:47.686: E/AndroidRuntime(6708): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974) 11-12 17:24:47.686: E/AndroidRuntime(6708): ... 11 more 11-12 17:24:47.716: W/ActivityManager(165): Force finishing activity cody.graham.scoutingdraft/.MyMenu 11-12 17:24:47.726: W/WindowManager(165): Failure taking screenshot for (246x410) to layer 21010 11-12 17:24:48.266: W/ActivityManager(165): Activity pause timeout for ActivityRecord{41980720 cody.graham.scoutingdraft/.MyMenu} </code></pre>
 

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