title: Android: Application force closing as soon as it opens
body: <p>I'm tinkering around with android on Netbeans and did a simple math application. Somewhere along the way the application suddenly force closes as soon as it opens(On the emulator)... I tried commenting all the code in the class that hosts the main activity but to no avail. Since it doesn't give me a specific error message, I feel kind of lost. </p>
  
  <p>Any reason why this is happening?</p>
  
  <p>Here is the layout file as requested:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:orientation="vertical"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent"&gt;
      &lt;TextView  android:id="@+id/result"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"
          android:text=""/&gt;
          &lt;LinearLayout android:orientation="horizontal"
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"&gt;
  
          &lt;TextView android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:text="@string/number" /&gt;
          &lt;EditText android:id="@+id/n"
            android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:layout_weight="1"
                          android:numeric="decimal"/&gt;
                  &lt;Button android:id="@+id/calc"
                    android:text="@string/calculate"
                          android:layout_width="wrap_content"
                          android:layout_height="wrap_content" /&gt;
      &lt;/LinearLayout&gt;
  &lt;/LinearLayout&gt;
  </code></pre>
  
  <p>As suggested I checked logcat and this is the list of errors</p>
  
  <pre><code>E/AndroidRuntime(  881): Uncaught handler: thread main exiting due to uncaught exception
  E/AndroidRuntime(  881): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{org.me.mathdroid/org.me.mathdroid.MainActivity}: java.lang.NullPointerException
  E/AndroidRuntime(  881):        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2324)
  E/AndroidRuntime(  881):        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417)
  E/AndroidRuntime(  881):        at android.app.ActivityThread.access$2100(ActivityThread.java:116)
  E/AndroidRuntime(  881):        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1794)
  E/AndroidRuntime(  881):        at android.os.Handler.dispatchMessage(Handler.java:99)
  E/AndroidRuntime(  881):        at android.os.Looper.loop(Looper.java:123)
  E/AndroidRuntime(  881):        at android.app.ActivityThread.main(ActivityThread.java:4203)
  E/AndroidRuntime(  881):        at java.lang.reflect.Method.invokeNative(NativeMethod)
  E/AndroidRuntime(  881):        at java.lang.reflect.Method.invoke(Method.java:521)
  E/AndroidRuntime(  881):        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
  E/AndroidRuntime(  881):        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
  E/AndroidRuntime(  881):        at dalvik.system.NativeStart.main(Native Method)
  
  E/AndroidRuntime(  881): Caused by: java.lang.NullPointerException
  E/AndroidRuntime(  881):        at android.app.Activity.findViewById(Activity.java:1610)
  E/AndroidRuntime(  881):        at org.me.mathdroid.MainActivity.&lt;init&gt;(MainActivity.java:22)
  E/AndroidRuntime(  881):        at java.lang.Class.newInstanceImpl(Native Method)
  E/AndroidRuntime(  881):        at java.lang.Class.newInstance(Class.java:1472)
  E/AndroidRuntime(  881):        at android.app.Instrumentation.newActivity(Instrumentation.java:1097)
  E/AndroidRuntime(  881):        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2316)
  E/AndroidRuntime(  881):        ... 11 more
  </code></pre>