android - Null returned on querying content resolver for image absolute path -

i developing android app, pick photo gallery. in method onactivityresult(), have following codes:

protected void onactivityresult(int requestcode, int resultcode, intent intent) {     // todo auto-generated method stub     super.onactivityresult(requestcode, resultcode, intent);     if(requestcode==pick_photo && resultcode==result_ok){          this.picuri=intent.getdata();          string[] proj = { mediastore.images.media.data };         cursor cursor = this.getapplicationcontext().                 getcontentresolver().query(this.picuri,  proj, null, null, null);         int column_index =  cursor.getcolumnindexorthrow(mediastore.images.media.data);         cursor.movetofirst();         string path=cursor.getstring(column_index);         cursor.close();       } 

but path returned cursor null. can possible reason?

i don't know what's value of uri , retrieving intent result in this.picuri have use one

in query change uri this.picuri

like,

this.picuri=intent.getdata();  string[] proj = { mediastore.images.media.data }; cursor cursor = this.getapplicationcontext().                 getcontentresolver().query(this.picuri,  proj, null, null, null);