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Getting null pointer exception changing text in fragment programmatically  RSS feed

 
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Hello there,I'm new to Android ,i Want to change the Text in a fragment programatically .My problem is that I'm getting an error like this- Attempt to invoke virtual method 'int android.os.Bundle.getInt(java.lang.String)' on a null object reference

I'm sending data from this Activity


to this Tab_Activity



and again I'm passing this data to a Fragment,

TipsFragment



Please any one help me clear this error.



 
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The first things that jumps out is that in line 30/31 of Tab_Activity you're creating a fragment which is then not used - so it will be be garbage-collected quickly. How are you actually using the fragment?
 
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I'm using this fragment in a Viewpager contained in a Tab Layout
 
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First I'm going to send a child position of an ExpandablelistView from an Activity to TabActivity,After setting up its Layout the TabActivity(Tablayout with 2 tabs and 2 fragmnets inside viewpager) gonna send the data it got to TipsFragment and it will populate the textview according to the childposition it got and actually i have 2 fragments i posted only one,please forgive me if I didn't give the right info you needed.
 
Tim Moores
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I'm using this fragment in a Viewpager contained in a Tab Layout


OK, so there's more code in Tab_Activity which you didn't post? Well, it's hard to tell what's going on without seeing the relevant code bits.

The first thing to try is to call getArguments in the onCreate method rather than the onCreateView method. But that only makes sense if  the fragment is actually being used (as opposed to just being created), and the code you posted doesn't show that part.
 
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Here's the full code on TabActivity,



and Thanks for Replying..
 
Tim Moores
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It's as I suspected: the fragment to which you add the parameter in lines 45 to 48 is not used. Instead, you create another instance of the fragments in lines 61 and 62 to which you're not adding any parameters. Those are the ones that actually get used in the ViewPager.
 
Tim Moores
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By the way, if you have exactly two views (or another small, fixed number of views) between which you want to switch, it would probably be easier to use a ViewFlipper rather than a ViewPager. No need to deal with fragments or adapters that way.
 
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Tim Moores wrote:It's as I suspected: the fragment to which you add the parameter in lines 45 to 48 is not used. Instead, you create another instance of the fragments in lines 61 and 62 to which you're not adding any parameters. Those are the ones that actually get used in the ViewPager.



How do i do that ?
 
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Tim Moores wrote:It's as I suspected: the fragment to which you add the parameter in lines 45 to 48 is not used. Instead, you create another instance of the fragments in lines 61 and 62 to which you're not adding any parameters. Those are the ones that actually get used in the ViewPager.



Ah.,It Worked Man as You said,I used the already created Fragment instance now.,It worked great.Thank you for your time..
 
It is sorta covered in the JavaRanch Style Guide.
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