• Post Reply
  • Bookmark Topic Watch Topic
  • New Topic

JTabbedPane.setTitleAt not working

 
Adam Cripps
Ranch Hand
Posts: 41
Eclipse IDE Linux Ubuntu
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
I've got a small method which I want to iterate through a JTabbedPane and String [] to set the title:



However, with this I get the error NullPointerException:



Line 43 is the tabbedPane.setTitleAt - the tabbedPane is there and it has 11 tabs - so why would I get NullPointerException?
TIA
Adam
 
Riaan Nel
Ranch Hand
Posts: 160
IntelliJ IDE Ubuntu VI Editor
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Post a SSCCE.
 
Rob Spoor
Sheriff
Pie
Posts: 20659
64
Chrome Eclipse IDE Java Windows
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
The exception ends at that line, so that means that on that line something before a . or array access is null. There is only one culprit: tabbedPane.
 
Adam Cripps
Ranch Hand
Posts: 41
Eclipse IDE Linux Ubuntu
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Thanks.

tabbedPane has an instance which has tabs - am I thinking that this doesn't work correctly? This is how I set the constructor up:

 
Rob Spoor
Sheriff
Pie
Posts: 20659
64
Chrome Eclipse IDE Java Windows
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Adam Cripps wrote:

That's an often made error. You did not initialize your instance variable but have instead created a local variable that shadows the instance field. This local variable is initialized. Simply remove the type declaration of that local variable and you will use the instance variable instead.
 
Adam Cripps
Ranch Hand
Posts: 41
Eclipse IDE Linux Ubuntu
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
The proverbial "D'Oh!" - many thanks.
 
Rob Spoor
Sheriff
Pie
Posts: 20659
64
Chrome Eclipse IDE Java Windows
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
You're welcome.
 
  • Post Reply
  • Bookmark Topic Watch Topic
  • New Topic