Reputation: 81
I am trying to fill an array of an "Runners" with an information in an ArrayList but I get a null pointer exception. I've printed out the size of both the arraylist and the array of Runners and they are what they should be.
--I only included code that I thought was necessary to solve the problem, please comment if you need more
private Runner r[];
private EditText runnerName,trackLength,raceDistance;
private ArrayList<String> runners = new ArrayList<String>();
public void onClickSetRunner(View v){
runners.add(runnerName.getText().toString());
runnerName.setText("");
}
public void onClickFinish(View v){
r = new Runner[runners.size()];
int i =0;
for(String name : runners){
r[i].setFirst(name);
i++;
}
}
Logcat (sorry I couldnt get it formatted)
04-15 09:09:45.009: E/AndroidRuntime(28225): FATAL EXCEPTION: main
04-15 09:09:45.009: E/AndroidRuntime(28225): Process: com.example.runtracker, PID: 28225
04-15 09:09:45.009: E/AndroidRuntime(28225): java.lang.IllegalStateException: Could not execute method of the activity
04-15 09:09:45.009: E/AndroidRuntime(28225): at android.view.View$1.onClick(View.java:3865)
04-15 09:09:45.009: E/AndroidRuntime(28225): at android.view.View.performClick(View.java:4480)
04-15 09:09:45.009: E/AndroidRuntime(28225): at android.view.View$PerformClick.run(View.java:18673)
04-15 09:09:45.009: E/AndroidRuntime(28225): at android.os.Handler.handleCallback(Handler.java:733)
04-15 09:09:45.009: E/AndroidRuntime(28225): at android.os.Handler.dispatchMessage(Handler.java:95)
04-15 09:09:45.009: E/AndroidRuntime(28225): at android.os.Looper.loop(Looper.java:157)
04-15 09:09:45.009: E/AndroidRuntime(28225): at android.app.ActivityThread.main(ActivityThread.java:5872)
04-15 09:09:45.009: E/AndroidRuntime(28225): at java.lang.reflect.Method.invokeNative(Native Method)
04-15 09:09:45.009: E/AndroidRuntime(28225): at java.lang.reflect.Method.invoke(Method.java:515)
04-15 09:09:45.009: E/AndroidRuntime(28225): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1069)
04-15 09:09:45.009: E/AndroidRuntime(28225): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:885)
04-15 09:09:45.009: E/AndroidRuntime(28225): at dalvik.system.NativeStart.main(Native Method)
04-15 09:09:45.009: E/AndroidRuntime(28225): Caused by: java.lang.reflect.InvocationTargetException
04-15 09:09:45.009: E/AndroidRuntime(28225): at java.lang.reflect.Method.invokeNative(Native Method)
04-15 09:09:45.009: E/AndroidRuntime(28225): at java.lang.reflect.Method.invoke(Method.java:515)
04-15 09:09:45.009: E/AndroidRuntime(28225): at android.view.View$1.onClick(View.java:3860)
04-15 09:09:45.009: E/AndroidRuntime(28225): ... 11 more
04-15 09:09:45.009: E/AndroidRuntime(28225): Caused by: java.lang.NullPointerException
04-15 09:09:45.009: E/AndroidRuntime(28225): at com.example.runtracker.MainActivity.onClickFinish(MainActivity.java:99)
04-15 09:09:45.009: E/AndroidRuntime(28225): ... 14 more
Upvotes: 0
Views: 159
Reputation: 4840
You created a new array of runners in onClickFinish
. However, you don't create new Runner objects in the array so r[i]
is null.
Upvotes: 0
Reputation: 152817
You haven't actually initialized r[i]
:
r = new Runner[runners.size()];
int i =0;
for(String name : runners){
r[i].setFirst(name);
you have an array or Runner
s but each entry in the array is null
by default. Add
r[i] = new Runner();
to initialize an entry there.
Upvotes: 4
Reputation: 2081
initialize runnerName before u use it.
runnerName.setText("");
runners.add(runnerName.getText().toString());
Upvotes: -1