java.lang.NullPointerException in Arrayadapter in android -

null pointer exception during adding data on arrayadapter. getting error

e/androidruntime(9233): fatal exception: main

e/androidruntime(9233):java.lang.nullpointerexception e/androidruntime(9233): @ co.adapter.topiccustomdisplayarrayadapter.getview(topiccustomdisplayarrayadapter.java:415)

e/androidruntime(9233): @ co.utils.twowayview.obtainview(twowayview.java:5599) e/androidruntime(9233): @ co.utils.twowayview.onmeasure(twowayview.java:3899) e/androidruntime(9233): @ android.view.view.measure(view.java:12773)

doing on code:

 private view convertview;  holder holdertext = null; public topiccustomdisplayarrayadapter(context context,         arraylist<fieldmodel> arraylist) {     super(context, r.layout.custom_display, arraylist);     minflater = (layoutinflater) getcontext().getsystemservice(         context.layout_inflater_service);     customtopicad = arraylist;      mcontext = context;     options = new displayimageoptions.builder().cacheinmemory(true)         .cacheondisc(true).considerexifparams(true)         .bitmapconfig(bitmap.config.rgb_565).build();     }      @override     public view getview(final int position, view cv, viewgroup parent) {      convertview = cv;      adtypestring = customtopic.get(position).getad_type();      if (adtypestring.equalsignorecase("text ads")) {          if (convertview == null) {         convertview = minflater.inflate(r.layout.text_view,             parent, false);          holdertext = new holder();         holdertext.textrelativelayout = (relativelayout) convertview             .findviewbyid(r.id.relativetextadview);          convertview.settag(holdertext);         } else {         holdertext = (holder) convertview.gettag();         }         int widthtextad = integer.parseint(customtopicad.get(position)             .getwidht());         int heighttextad = integer.parseint(customtopicad.get(position)             .getheight();          holdertext.textrelativelayout.getlayoutparams().width = widthtextad;         holdertext.textrelativelayout.getlayoutparams().height = heighttextad;         } else if (adtypestring.equalsignorecase("image ads")) {        // display layout         }    return convertview;    }   public static class holder { // display ads resrouces  public relativelayout textrelativelayout;   } 

height , widht getting not set height , widht on relative layout. getting on line:

holdertext.textrelativelayout.getlayoutparams().width = widthtextad; holdertext.textrelativelayout.getlayoutparams().height = heighttextad;

any idea how correction error. here arraylist size 5.

it seems getlayoutparams() causes nullpointer because textrelativelayout has not have layout params or size.if want set textrelativelayout's size,you may consider set layoutparams of view. change

holdertext.textrelativelayout.getlayoutparams().width = widthtextad; holdertext.textrelativelayout.getlayoutparams().height = heighttextad; 

to

twowayview.layoutparams lp = new twowayview.layoutparams(widthtextad, heighttextad); holdertext.textrelativelayout.setlayoutparams(lp);