Use of toolbar

1. establish menu

<?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/addFriend"
        android:icon="@drawable/addfriend"
        android:orderInCategory="80"
        android:title=" Add friends "
        app:showAsAction="never" />

    <item
        android:id="@+id/newChat"
        android:icon="@drawable/morechat"
        android:orderInCategory="90"
        android:title=" New group chat "
        app:showAsAction="never" />

    <item
        android:id="@+id/scan"
        android:icon="@drawable/scan"
        android:orderInCategory="100"
        android:title=" scan "
        app:showAsAction="never"/>
    <item
        android:id="@+id/money"
        android:icon="@drawable/money"
        android:orderInCategory="100"
        android:title=" Collection and payment "
        app:showAsAction="never"/>

</menu>

2.activity

Layout introduction toolbar

        <androidx.appcompat.widget.Toolbar
            android:background="@color/blue"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            android:id="@+id/toolbar"/>

setSupportActionBar(mMainBinding.toolbar);  No call, no display toolbar
getSupportActionBar().setTitle(" Ring letter  app");   Set up toolbar The title of the 
mMainBinding.toolbar.setOnMenuItemClickListener(listener);  Set listener 

    rewrite onCreateOptionsMenu  load menu
@Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.toolbar, menu);
        return true;
    }

     rewrite onPrepareOptionsPanel  load menu The icon 
@Override
    protected boolean onPrepareOptionsPanel(View view, Menu menu) {
        if (menu != null) {
            if (menu.getClass() == MenuBuilder.class) {
                try {
                    Method m = menu.getClass().getDeclaredMethod("setOptionalIconsVisible", Boolean.TYPE);
                    m.setAccessible(true);
                    m.invoke(menu, true);
                } catch (Exception e) {
                }
            }
        }
        return super.onPrepareOptionsPanel(view, menu);
    }

Monitor

    private final Toolbar.OnMenuItemClickListener listener = new Toolbar.OnMenuItemClickListener() {
        @Override
        public boolean onMenuItemClick(MenuItem item) {
            switch (item.getItemId()) {
                case R.id.addFriend:
                    Toast.makeText(MainActivity.this, "addFriend", Toast.LENGTH_SHORT).show();
                    break;
                case R.id.scan:
                    Toast.makeText(MainActivity.this, "scan", Toast.LENGTH_SHORT).show();
                    break;
                case R.id.newChat:
                    Toast.makeText(MainActivity.this, "newChat", Toast.LENGTH_SHORT).show();
                    // Pop up custom popWindow
                    //popUpMyOverflow();
                    break;
                case R.id.money:
                    Toast.makeText(MainActivity.this, "money", Toast.LENGTH_SHORT).show();
                    break;
            }
            return false;
        }
    };