CODEWITHSUNDEEP
android
swetha
swetha

Reputation: 45

how to use toggle button in fragment

This is my Class Code in which i want to acess toggle button but am getting nullpointer exception.i used ViewHolder Class to get the view from Layout and Acessing them here.but unable to find the error why am getting this NUllPOInter at
holder.stateOnOff.setText(); line

 public class ColorSchemeFragment extends Fragment {

public  class ViewHolder {
    public  ToggleButton toggleButton;
    public TextView stateOnOff;
}
ViewHolder holder = new ViewHolder();

@Override
public View onCreateView(LayoutInflater inflater, 
 ViewGroup container,Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.colorscheme, container, false);
    holder.toggleButton = ((ToggleButton) container.findViewById(R.id.toggle));
    holder.stateOnOff=(TextView)container.findViewById(R.id.tvstate);
    holder.stateOnOff.setText("OFF");
    holder.toggleButton.setOnCheckedChangeListener(new OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {
            if(isChecked){
                holder.stateOnOff.setText("On");
            }else{
                holder.stateOnOff.setText("Off");
            }
                }
            });
        return view;
        }
       }

Upvotes: 2

Views: 4002

Answers (1)

Miro Markaravanes
Miro Markaravanes

Reputation: 3366

No need to use a ViewHolder. They are for recycling views through a ListView or other scrollable views.

Also the container object holds the parent layout, and not the one you are inflating. So it does not contain the views you are looking up and returns null.

public class ColorSchemeFragment extends Fragment {

public ToggleButton toggleButton;
public TextView stateOnOff;

@Override
public View onCreateView(LayoutInflater inflater, 
 ViewGroup container,Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.colorscheme, container, false);
    toggleButton = (ToggleButton) view.findViewById(R.id.toggle);
    stateOnOff=(TextView) view.findViewById(R.id.tvstate);
    stateOnOff.setText("OFF");
    toggleButton.setOnCheckedChangeListener(new OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {
            if(isChecked){
                stateOnOff.setText("On");
            }else{
                stateOnOff.setText("Off");
            }
                }
            });
        return view;
        }
     }

Upvotes: 2

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