My application is stopping

Question

So I'm trying to make the button redirect to another class, my application is stopping when I try to click the button Play and this is what the logcat says

Caused by: java.lang.NullPointerException at com.example.kenneth.rusa.Play.onCreate(Play.java:26)

Play, java:26 is

Button play = (Button) findViewById(R.id.playb);
play.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        startActivity(new Intent(Play.this, GamePanelEasy.class));
}

Here's my manifest:

<activity android:screenOrientation="landscape" android:name=".Play">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.DEFAULT" />
    </intent-filter>
</activity>

I don't have any errors but it's still crashing, I don't know why the logcat says I have error in line 26 which is play.setOnClickListener(new View.OnClickListener(){ }

Thanks for the help guys I found out what's my problem playb was been duplicated from another class I changed it to easyb so it works fine now thanks!

I don't know which is line 26, but I would assume your play button variable is null for some reason. — Richard Goodman, Sep 05 '16 at 12:17
@KennethAbuel if you are sure that Button play = (Button) findViewById(R.id.playb); referencing to correct id that is inside the same layout of this activity then try clean and building the project or changing the id.. — Amar, Sep 05 '16 at 12:27
@KennethAbuel May be have duplicate id's with same name or you are taking reference of wrong id in *code*. — Jay Rathod, Sep 05 '16 at 12:39

score 0 · Answer 1 · answered Sep 05 '16 at 12:18

0

If your app crashes in between lines you posted there is only one possibility. You are trying to invoke setOnClickListener() method to a null reference here:

play.setOnClickListener(new View.OnClickListener() {

Check if R.id.playb id is in layout you inflate in onCreate().

answered Sep 05 '16 at 12:18

Mr Quattro

331
1
5

How do I check if R.id.playb ID is in layout? – anomalyyaboi Sep 05 '16 at 12:24
Open your layout file, find a button you want to attach onClickListener to and check if its `id` is set to `R.id.playb`. Should look like this: `android:id="@+id/R.id.playb"` – Mr Quattro Sep 05 '16 at 12:25
Oh, I found out why it's crashing there's a duplicate R.id.play, I didn't notice it but I found it out now! Thank you! – anomalyyaboi Sep 05 '16 at 12:31

score 0 · Answer 2 · answered Sep 05 '16 at 12:29

0

<activity android:name="GamePanelEasy"
   android:label="@string/app_name">
   <intent-filter>
       <action android:name="android.intent.action.VIEW" />
   </intent-filter>
</activity>

--have you declare your second activity in the manifest?

answered Sep 05 '16 at 12:29

Francesco Taioli

2,687
1
19
34

My application is stopping

2 Answers2