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Horacio Chacon
670 PointsAccessing Strings.xml from Factbook declaring an array.
I have a fatal exception when trying to innitialize the app. java.lang.ExceptionInInitializerError caused by java.lang.NullPointerException
This is my FunFactsActivity
package pe.Anastomosis.funfacts;
import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.Toast;
public class FunFactsActivity extends Activity {
public static final String TAG = FunFactsActivity.class.getSimpleName();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_fun_facts);
// Declare our View variables and assign the Views from the layout file
final TextView factlabel = (TextView) findViewById(R.id.FactTextView);
final Button showFactButton = (Button) findViewById(R.id.BotonMostrarFact);
final RelativeLayout mRelativeLayout = (RelativeLayout) findViewById(R.id.RelativeLayout);
View.OnClickListener listener = new View.OnClickListener() {
@Override
public void onClick(View view) {
String fact = FactBook.getFact();
//Update the label with our dynamic fact
factlabel.setText(fact);
int color = ColorWheel.getColor();
mRelativeLayout.setBackgroundColor(color);
showFactButton.setTextColor(color);
}
};
showFactButton.setOnClickListener(listener);
}
}
This is my Factbook
package pe.Anastomosis.funfacts;
import android.content.res.Resources;
import java.util.Random;
/**
* Created by horacio on 2/06/15.
*/
public class FactBook {
//member variable (propierties about the object)
public static Resources res;
public static String[] mfacts = res.getStringArray(R.array.Funfacts);
// Method (abilities:things the object can do)
public static String getFact() {
String fact = "";
// Randomly select a fact
Random randomGenerator = new Random(); // construct a new random number generator
Random randomMeGenerator = new Random();
int randomNumber = randomGenerator.nextInt(mfacts.length);
int randomMe = randomMeGenerator.nextInt(20);
//Ramdom "hi"
if (randomMe == 5){
fact = "Hi";
}
else {
//Utiliza el valor de randomNumber para asignar del array a fact
fact = mfacts[randomNumber];
}
return fact;
}
}
And my strings.xml file
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">Fun Facts</string>
<string name="hello_world">Hello world!</string>
<string name="action_settings">Settings</string>
<string-array name="Funfacts">
<item>Ants stretch when they wake up in the morning.</item>
<item>Ostriches can run faster than horses</item>
<item>Olympic gold medals are actually made mostly of silver</item>
<item>You are born with 300 bones; by the time you are an adult you will have 206.</item>
<item>It takes about 8 minutes for light from the Sun to reach Earth.</item>
<item>Some bamboo plants can grow almost a meter in just one day.</item>
<item>The state of Florida is bigger than England.</item>
<item>Some penguins can leap 2-3 meters out of the water.</item>
<item>On average, it takes 66 days to form a new habit.</item>
<item>Mammoths still walked the earth when the Great Pyramid was being built.</item>
<item>Treehouse is not actually in a tree.</item>
</string-array>
</resources>
And my log
06-13 19:43:59.721 2324-2324/pe.Anastomosis.funfacts E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: pe.Anastomosis.funfacts, PID: 2324
java.lang.ExceptionInInitializerError
at pe.Anastomosis.funfacts.FunFactsActivity$1.onClick(FunFactsActivity.java:32)
at android.view.View.performClick(View.java:4438)
at android.view.View$PerformClick.run(View.java:18422)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
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 pe.Anastomosis.funfacts.FactBook.<clinit>(FactBook.java:16)
at pe.Anastomosis.funfacts.FunFactsActivity$1.onClick(FunFactsActivity.java:32)
at android.view.View.performClick(View.java:4438)
at android.view.View$PerformClick.run(View.java:18422)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
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)
Thank you very much in advance
2 Answers
Kristian Terziev
28,449 PointsWell on line 32 in your FunFactsActivity you're trying to access the facts directly from the class. That causes the exception. Instead, try instantiating the class first, and then use the created object to get facts. Something like this:
FactBook factBook = new FactBook();
factlabel.setText(factBook.getFact()); // I would recommend renaming the label to "factLabel" (camelCase)
Horacio Chacon
670 PointsThanks, but i still have this error log even with your changes.
06-14 12:47:49.145 10231-10231/pe.Anastomosis.funfacts E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: pe.Anastomosis.funfacts, PID: 10231
java.lang.ExceptionInInitializerError
at pe.Anastomosis.funfacts.FunFactsActivity$1.onClick(FunFactsActivity.java:32)
at android.view.View.performClick(View.java:4438)
at android.view.View$PerformClick.run(View.java:18422)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
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 pe.Anastomosis.funfacts.FactBook.<clinit>(FactBook.java:15)
at pe.Anastomosis.funfacts.FunFactsActivity$1.onClick(FunFactsActivity.java:32)
at android.view.View.performClick(View.java:4438)
at android.view.View$PerformClick.run(View.java:18422)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
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)