如何在 Xamarin Android Fragment 中加载工具栏布局

Question

I'm trying to create a basic toolbar that I can place clickable icons on. This will be inside a separate fragment to the starting activity page.

Fragment Code:

 public void onCreate(Bundle savedInstanceState)
    {
        base.OnCreate(savedInstanceState);
        SetHasOptionsMenu(true);
    }

    public override View OnCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
    {
        base.OnCreateView(inflater, container, savedInstanceState);

        //Inflates the new xml into the fragment 
        var view = inflater.Inflate(Resource.Layout.chord_progression, container, false);
        mToolbar = view.FindViewById<Android.Support.V7.Widget.Toolbar>(Resource.Id.toolbar);
        ((AppCompatActivity)this.Activity).SetSupportActionBar(mToolbar);
        ((AppCompatActivity)this.Activity).SupportActionBar.Title = "Progression Maker";

        //Button that when pressed returns to the login screen
        btnLogout = view.FindViewById<Button>(Resource.Id.btnLogout);
        btnLogout.Click += (sender, EventArts) =>
        {
            //Drops back into main activity
            var intent = new Intent(Activity, typeof(MainActivity));
            StartActivity(intent);
        };

        //Calls the to play the chords selected by the user
        btnPlay = view.FindViewById<Button>(Resource.Id.PlayChords);
        btnPlay.Click += (sender, EventArgs) => PlayChords(sender, EventArgs);

        //Calls this to generate random chords from the selected key
        btnRandomise = view.FindViewById<Button>(Resource.Id.btnRandomise);
        btnRandomise.Click += (sender, EventArgs) => randomiseChords(sender, EventArgs);

        //Spinners to store tonality and key signatures
        key_Spinner = view.FindViewById<Spinner>(Resource.Id.key_Spinner);
        tonality_Spinner = view.FindViewById<Spinner>(Resource.Id.tonality_Spinner);

        //Spinners that allow the user to select the individual chord they want to use
        chord1_spinner = view.FindViewById<Spinner>(Resource.Id.chord1);
        chord2_spinner = view.FindViewById<Spinner>(Resource.Id.chord2);
        chord3_spinner = view.FindViewById<Spinner>(Resource.Id.chord3);
        chord4_spinner = view.FindViewById<Spinner>(Resource.Id.chord4);

        chord1_spinner.ItemSelected += new EventHandler<AdapterView.ItemSelectedEventArgs>(generateChordOne);
        chord2_spinner.ItemSelected += new EventHandler<AdapterView.ItemSelectedEventArgs>(generateChordTwo);
        chord3_spinner.ItemSelected += new EventHandler<AdapterView.ItemSelectedEventArgs>(generateChordThree);
        chord4_spinner.ItemSelected += new EventHandler<AdapterView.ItemSelectedEventArgs>(generateChordFour);

        //Calls procedure that changes the spinners content based on the selection of another
        tonality_Spinner.ItemSelected += new EventHandler<AdapterView.ItemSelectedEventArgs>(tonalitySpinner_ItemSelected);
        key_Spinner.ItemSelected += new EventHandler<AdapterView.ItemSelectedEventArgs>(keySpinner_ItemSelected);

        //Brings up the save dialog
        btnSave = view.FindViewById<ImageButton>(Resource.Id.SaveButton);
        btnSave.Click += (sender, EventArgs) =>
        {
            //Ensures thet the user is unable to access save function if they have nothing to save
            if (tonality_Spinner.SelectedItemPosition == 0)
            {
                Toast.MakeText(this.Activity, "Nothing to save!", ToastLength.Long).Show();
            }
            else if (UserID == "-1" && tonality_Spinner.SelectedItemPosition != 0)
            {
                Toast.MakeText(this.Activity, "You cannot save progressions as a guest!", ToastLength.Long).Show();
            }
            else if (UserID == "-1" && tonality_Spinner.SelectedItemPosition == 0)
            {
                Toast.MakeText(this.Activity, "You cannot save progressions as a guest! And there's nothing to save!", ToastLength.Long).Show();
            }
            else 
            {
                //Gets the contents of the selected items of the spinners as strings
                string chord1 = chord1_spinner.SelectedItem.ToString();
                string chord2 = chord2_spinner.SelectedItem.ToString();
                string chord3 = chord3_spinner.SelectedItem.ToString();
                string chord4 = chord4_spinner.SelectedItem.ToString();
                string tonality = tonality_Spinner.SelectedItem.ToString();
                string keysig = key_Spinner.SelectedItem.ToString();

                FragmentTransaction transaction = FragmentManager.BeginTransaction();
                DialogSave Save_Dialog = new DialogSave(chord1, chord2, chord3, chord4, tonality, keysig, UserID);
                Save_Dialog.Show(transaction, "dialog fragment");
            }

        };

        btnLoad = view.FindViewById<ImageButton>(Resource.Id.LoadButton);
        btnLoad.Click += (sender, EventArgs) =>
        {
            if (UserID == "-1")
            {
                Toast.MakeText(this.Activity, "Can't load as a guest!", ToastLength.Long).Show();
            }
            else
            {
                btnLoad_Click(sender, EventArgs);
            }
        };


        //Brings up the dialog fragment for the help tab
        btnHelp = view.FindViewById<ImageButton>(Resource.Id.HelpButton);
        btnHelp.Click += (sender, EventArgs) =>
        {
            //Pull up dialog
            FragmentTransaction transaction = FragmentManager.BeginTransaction();
            DialogHelp Help_Dialog = new DialogHelp();
            Help_Dialog.Show(transaction, "dialog fragment");
        };

        if (UserID == "-1")
        {
            btnLogout.Text = "Sign In";
        }

        return view;
    }

    public void OnCreateOptionsMenu(IMenu menu, MenuInflater inflater)
    {
        inflater.Inflate(Resource.Menu.toolbar_menu, menu);
        base.OnCreateOptionsMenu(menu, inflater);
    }

    public override bool OnOptionsItemSelected(IMenuItem item)
    {
        string textToShow;
        if (item.ItemId == Resource.Id.menu_info)
            textToShow = "Learn more about us affa";
        else
            textToShow = "overflooow";
        return base.OnOptionsItemSelected(item);
    }

Layout for fragment:

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:minWidth="25px"
    android:minHeight="25px">
    <android.support.v7.widget.Toolbar
        xmlns:app="http://schemas.android.com/apk/res-auto"
        android:id = "@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:minHeight = "?android:attr/actionBarSize"
        android:background = "?android:attr/colorPrimary"
        android:elevation = "4dp"
        android:theme = "@style/ThemeOverlay.AppCompat.Dark.ActionBar"
        android:fitsSystemWindows = "true"/>
</LinearLayout>

Toolbar layout:

<?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/menu_info"
        android:icon ="@drawable/ic_help_icon"
        app:showAsAction ="ifRoom"
        android:title ="Info"/>
  <item android:id ="@+id/menu_overflow"
        app:showAsAction ="never"
        android:title="Overflow"/>
</menu>

Style page:

<?xml version="1.0" encoding = "utf-8"?>
<resources>
  <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/colorAccent</item>
    <item name="windowActionBar">false</item>
    <item name="windowNoTitle">true</item>
  </style>

</resources>

I have already made my main activity take from 'AppCompatActivity'. I also already have reference my theme in the Activity. I have also included 'SetHasOptionsMenu(true)' in the OnCreate. The problem is it sets the title just fine but it doesn't seem to be calling the OnCreateOptionsMenu. Any ideas?

Answer 1

Make sure to include this your main activity to allow your fragment to create the toolbar:

 public override bool OnCreateOptionsMenu(IMenu menu)
    {
        MenuInflater.Inflate(Resource.Menu.toolbar_menu, menu);
        return base.OnCreateOptionsMenu(menu);
    }