I am getting a NullPointerException when my code tries to access the value in a key/value pair created by onSaveInstanceState method of Activity class.
I set break points and I know for fact my Bundle is not null and it contains references to my key/values. I dont understand why I am getting this runtime error. Here are my codes for onSaveInstanceState
@Override
protected void onSaveInstanceState(Bundle outState) {
int mPoints = winCount;
int hPoints = loseCount;
String reTextView = resultsTextView.getText().toString();
String pTextView = pointsTextView.getText().toString();
String roTextView = rollTextView.getText().toString();
outState.putInt("MY_POINTS", mPoints);
outState.putInt("HOUSE_POINTS", hPoints);
outState.putString("RESULTS", reTextView);
outState.putString("POINTS", pTextView);
outState.putString("ROLL", roTextView);
super.onSaveInstanceState(outState);
}
and here is my code to restore the state on the onCreate method
// check if app just started or is being restored from memory
if ( savedInstanceState == null ) // the app just started running
{
winCount = 0;
loseCount = 0;
}
else
{
winCount = savedInstanceState.getInt("MY_POINTS");
loseCount = savedInstanceState.getInt("HOUSE_POINTS");
resultsTextView.setText(String.valueOf(savedInstanceState.getString("RESULTS")));
pointsTextView.setText(String.valueOf(savedInstanceState.getString("POINTS")));
rollTextView.setText(String.valueOf(savedInstanceState.getString("ROLL")));
}
I get the runtime error on line that starts with resultsTextView.setText... and here is contents of the savedInstanceState Bundle retrieved from break points in debug mode
Bundle[{RESULTS=Roll Again, MY_POINTS=2, POINTS=Your Point is 8,
HOUSE_POINTS=2,
android:viewHierarchyState=Bundle[{android:Panels=android.util.SparseArray@421c5560,
android:views=android.util.SparseArray@421c5358,
android:ActionBar=android.util.SparseArray@421c57f8}], ROLL=You Rolled
Easy Four}]
as you can see all my strings have a value, the interesting thing is that I dont get the NullPointerException runtime error on int variables (winCount and loseCount) but I am getting it at string values. I appreciate any help.
Update: here is the whole error log from log cat, I have resultsTextView.setText... at line 68 (within the else block on onCreat())
W/dalvikvm(27797): threadid=1: thread exiting with uncaught exception (group=0x418b6700)
E/AndroidRuntime(27797): FATAL EXCEPTION: main
E/AndroidRuntime(27797): java.lang.RuntimeException: Unable to start activity ComponentInfo{…}: java.lang.NullPointerException
E/AndroidRuntime(27797): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
E/AndroidRuntime(27797): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
E/AndroidRuntime(27797): at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:3740)
E/AndroidRuntime(27797): at android.app.ActivityThread.access$700(ActivityThread.java:141)
E/AndroidRuntime(27797): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1262)
E/AndroidRuntime(27797): at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime(27797): at android.os.Looper.loop(Looper.java:137)
E/AndroidRuntime(27797): at android.app.ActivityThread.main(ActivityThread.java:5103)
E/AndroidRuntime(27797): at java.lang.reflect.Method.invokeNative(Native Method)
E/AndroidRuntime(27797): at java.lang.reflect.Method.invoke(Method.java:525)
E/AndroidRuntime(27797): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
E/AndroidRuntime(27797): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
E/AndroidRuntime(27797): at dalvik.system.NativeStart.main(Native Method)
E/AndroidRuntime(27797): Caused by: java.lang.NullPointerException
E/AndroidRuntime(27797): at app.package.onCreate(AppName.java:68)
E/AndroidRuntime(27797): at android.app.Activity.performCreate(Activity.java:5133)
E/AndroidRuntime(27797): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
E/AndroidRuntime(27797): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
E/AndroidRuntime(27797): ... 12 more
here is my whole onCreate method, since many commentators requested to see the whole method. Hope it helps!
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity);
// check if app just started or is being restored from memory
if ( savedInstanceState == null ) // the app just started running
{
winCount = 0;
loseCount = 0;
}
else
{
winCount = savedInstanceState.getInt("MY_POINTS");
loseCount = savedInstanceState.getInt("HOUSE_POINTS");
resultsTextView.setText(savedInstanceState.getString("RESULTS"));
pointsTextView.setText(savedInstanceState.getString("POINTS"));
rollTextView.setText(savedInstanceState.getString("ROLL"));
}
die1 = (ImageView) findViewById(R.id.imageView1);
die2 = (ImageView) findViewById(R.id.imageView2);
dealButton = (Button) findViewById(R.id.dealButton);
resetButton = (Button) findViewById(R.id.resetButton);
resultsTextView = (TextView) findViewById(R.id.resultsTextView);
myPointsTextView = (TextView) findViewById(R.id.myPointstTextView);
housePointsTextView = (TextView) findViewById(R.id.housePointsTextView);
pointsTextView = (TextView) findViewById(R.id.pointsTextView1);
rollTextView = (TextView) findViewById(R.id.rollTextView);
dealButton.setOnClickListener(dealButtonListener);
resetButton.setOnClickListener(resetButtonLinstener);
//on shake event
mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mShakeDetector = new ShakeDetector(new OnShakeListener() {
@Override
public void onShake() {
game(rollDice());
}
});
resultsTextView.setTextColor(Color.BLACK);
myPointsTextView.setText(String.format("%s", winCount));
housePointsTextView.setText(String.format("%s", loseCount));
}
You should initialize your TextView
s before calling setText method. So onCreate should be like this:
setContentView(R.layout.activity);
die1 = (ImageView) findViewById(R.id.imageView1);
die2 = (ImageView) findViewById(R.id.imageView2);
dealButton = (Button) findViewById(R.id.dealButton);
resetButton = (Button) findViewById(R.id.resetButton);
resultsTextView = (TextView) findViewById(R.id.resultsTextView);
myPointsTextView = (TextView) findViewById(R.id.myPointstTextView);
housePointsTextView = (TextView) findViewById(R.id.housePointsTextView);
pointsTextView = (TextView) findViewById(R.id.pointsTextView1);
rollTextView = (TextView) findViewById(R.id.rollTextView);
// check if app just started or is being restored from memory
if ( savedInstanceState == null ) // the app just started running
{
winCount = 0;
loseCount = 0;
}
else
{
winCount = savedInstanceState.getInt("MY_POINTS");
loseCount = savedInstanceState.getInt("HOUSE_POINTS");
resultsTextView.setText(savedInstanceState.getString("RESULTS"));
pointsTextView.setText(savedInstanceState.getString("POINTS"));
rollTextView.setText(savedInstanceState.getString("ROLL"));
}
...
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