Selection of menu bar symbols

There are many menu symbols in Android studio. Select drawable


You can choose any symbol you want

code implementation

public class CrimeListFragment extends Fragment {

    public static final String SUBTITLE = "subtitle";
    private RecyclerView mRecyclerView;
    private CrimeAdpater mCrimeAdpater;


    private boolean mSubtitleVisible;


    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        //Accept menu options callback
        setHasOptionsMenu(true);
    }

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view=inflater.inflate(R.layout.crime_list_fragment,container,false);

        if(savedInstanceState!=null){
           mSubtitleVisible=savedInstanceState.getBoolean(SUBTITLE);
        }

        mRecyclerView=(RecyclerView)view.findViewById(R.id.crime_recycler);
        mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));

        updateUI();
        return view;
    }

    private class CrimeHolder extends RecyclerView.ViewHolder implements View.OnClickListener{

        private TextView list_title;
        private TextView list_date;

        Crime mCrime;
        public void bind(Crime crime){
            mCrime=crime;
            list_title.setText(crime.getTitle());
            list_date.setText(crime.getDate().toString());
        }

        public CrimeHolder(LayoutInflater inflater,ViewGroup parent){
            super(inflater.inflate(R.layout.crime_list_item,parent,false));

            list_title=(TextView)itemView.findViewById(R.id.list_title);
            list_date=(TextView)itemView.findViewById(R.id.list_date);

            itemView.setOnClickListener(this);
        }



        @Override
        public void onClick(View v) {
           // Toast.makeText(getActivity(), mCrime.getTitle()+"click!", Toast.LENGTH_SHORT).show();
           // Intent intent= new Intent(getActivity(),CrimeActivity.class);
           // Intent intent=CrimeActivity.newIntent(getActivity(),mCrime.getId());
            Intent intent= CrimePagerActivity.newIntent(getActivity(),mCrime.getId());

            startActivity(intent);
        }
    }


    private class CrimeAdpater extends RecyclerView.Adapter<CrimeHolder>{

        private List<Crime> mCrimes;

        public CrimeAdpater(List<Crime> crimes){
            mCrimes=crimes;
        }

        @Override
        public CrimeHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            LayoutInflater layoutInflater=LayoutInflater.from(getActivity());
            return new CrimeHolder(layoutInflater,parent);
        }

        @Override
        public void onBindViewHolder(CrimeHolder holder, int position) {

            Crime crime=mCrimes.get(position);
            holder.bind(crime);
        }

        @Override
        public int getItemCount() {
            return mCrimes.size();
        }
    }

    @Override
    public void onResume() {
        super.onResume();
        updateUI();
    }

    private void updateUI(){

        CrimeLab crimeLab=CrimeLab.getCrimeLab(getActivity());
        List<Crime> crimes=crimeLab.getCrimes();

//        mCrimeAdpater=new CrimeAdpater(crimes);
//        mRecyclerView.setAdapter(mCrimeAdpater);
        if(mCrimeAdpater==null){
            mCrimeAdpater=new CrimeAdpater(crimes);
            mRecyclerView.setAdapter(mCrimeAdpater);
        }else{
            mCrimeAdpater.notifyDataSetChanged();
        }

        updateSubtitle();
    }


//Create menu, import menu resource
    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        super.onCreateOptionsMenu(menu, inflater);
        inflater.inflate(R.menu.fragment_crime_list,menu);

        MenuItem subtitleItem=menu.findItem(R.id.show_subtitle);
        if(mSubtitleVisible){
            subtitleItem.setTitle("show");
        }else{
            subtitleItem.setTitle("hide");
        }
    }


    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()){
            case R.id.new_crime:
                Crime crime=new Crime();
                CrimeLab.getCrimeLab(getActivity()).addCrime(crime);
                Intent intent=CrimePagerActivity.newIntent(getActivity(),crime.getId());
                startActivity(intent);
                return true;
            case R.id.show_subtitle:
                mSubtitleVisible=!mSubtitleVisible;
                getActivity().invalidateOptionsMenu();
                updateSubtitle();
                return  true;
                default:
                    return super.onOptionsItemSelected(item);
        }
    }

//Show how many items there are
    public void updateSubtitle(){
        CrimeLab crimeLab=CrimeLab.getCrimeLab(getActivity());
        int crimeCount=crimeLab.getCrimes().size();
        String subtitle=getString(R.string.subtitle_format,crimeCount);

        if(!mSubtitleVisible){
            subtitle=null;
        }

        AppCompatActivity activity=(AppCompatActivity)getActivity();
        activity.getSupportActionBar().setSubtitle(subtitle);
    }
//When the screen rotates, the data is lost. Save it through the bundle and get it in the onCreateView method
    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putBoolean(SUBTITLE,mSubtitleVisible);
    }
}

Create menu file

Select res

Finally, the folder of menu and its xml file will be generated automatically

Code:

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">

    <item
        android:id="@+id/new_crime"
        android:icon="@drawable/ic_menu_add"
        android:title="@string/new_crime"
        app:showAsAction="ifRoom|withText"/>

    <item
        android:id="@+id/show_subtitle"
        android:title="@string/show_subtitle"
        app:showAsAction="ifRoom"/>
</menu>

app:showAsAction="ifRoom|withText":
It means that as long as the space is enough, the menu bar icon and text description will be displayed on the toolbar. If the space is only enough to display the icon, the text description will not be displayed, or only enough to display the text description, the icon will not be displayed
ifroom: let the operating system decide how to display the menu bar