FlyoutMenus

public class EmojiFlyoutMenu {

    static String getEmojiByUnicode(int unicode){
        return new String(Character.toChars(unicode));
    }

    public static class MenuItem extends FlyoutMenuView.MenuItem {

        int emojiCode;
        String emojiString;
        TextPaint textPaint;

        public MenuItem(int id, int emojiCode, float size, @ColorInt int color) {
            super(id);
            this.emojiCode = emojiCode;
            this.emojiString = getEmojiByUnicode(emojiCode);

            textPaint = new TextPaint();
            textPaint.setTextSize(size);
            textPaint.setTextAlign(Paint.Align.CENTER);
            textPaint.setStyle(Paint.Style.FILL);
            textPaint.setColor(color);
        }

        public int getEmojiCode() {
            return emojiCode;
        }

        @Override
        public void onDraw(Canvas canvas, RectF bounds, float degreeSelected) {
            canvas.drawText(emojiString, bounds.centerX(), bounds.centerY() - ((textPaint.descent() + textPaint.ascent()) / 2), textPaint);
        }
    }

    public static class ButtonRenderer extends FlyoutMenuView.ButtonRenderer {

        int emojiCode;
        String emojiString;
        Paint paint;
        TextPaint textPaint;

        public ButtonRenderer(int emojiCode, float size, @ColorInt int color) {
            super();

            this.setEmojiCode(emojiCode);

            paint = new Paint();
            paint.setAntiAlias(true);

            textPaint = new TextPaint();
            textPaint.setTextSize(size);
            textPaint.setTextAlign(Paint.Align.CENTER);
            textPaint.setStyle(Paint.Style.FILL);
            textPaint.setColor(color);
        }

        public int getEmojiCode() {
            return emojiCode;
        }

        public void setEmojiCode(int emojiCode) {
            this.emojiCode = emojiCode;
            this.emojiString = getEmojiByUnicode(this.emojiCode);
        }

        @Override
        public void onDrawButtonContent(Canvas canvas, RectF buttonBounds, @ColorInt int buttonColor, float alpha) {
            textPaint.setAlpha((int) (alpha * 255f));
            canvas.drawText(emojiString, buttonBounds.centerX(), buttonBounds.centerY() - ((textPaint.descent() + textPaint.ascent()) / 2), textPaint);
        }
    }
}

FlyoutMenuView smileyFlyoutMenu = findViewById(R.id.smileyFlyoutMenu); 

int[] emojiCodes = {
        0x1F60D, //smiling face heart shaped eyes
        0x1F605, // smiling face with open mouth and cold sweat
        0x1F60A, // smiling face
        0x1F613, // face with cold sweat
        0x1F61E, // disappointed face
        0x1F620, // angry face
        0x1F62D, // loudly crying face
        0x1F4A9, // pile of poo
};

@ColorInt int color = ContextCompat.getColor(this, R.color.smileyMenuCharColor);
float fontSizeInMenu = getResources().getDimension(R.dimen.smiley_menu_item_size) * 0.5f;
float fontSizeInButton = getResources().getDimension(R.dimen.flyout_menu_button_size) * 0.5f;

// build a List<> of EmojiFlyoutMenu.MenuItem
List<EmojiFlyoutMenu.MenuItem> menuItems = new ArrayList<>();
for (int code : emojiCodes) {
    menuItems.add(new EmojiFlyoutMenu.MenuItem(menuItems.size(), code, fontSizeInMenu, color));
}

// assign a GridLayout with 2 columns and unspecified rows (allows menu to grow vertically)
smileyFlyoutMenu.setLayout(new FlyoutMenuView.GridLayout(2, FlyoutMenuView.GridLayout.UNSPECIFIED));

// assign the menuItems via an ArrayAdapter
smileyFlyoutMenu.setAdapter(new FlyoutMenuView.ArrayAdapter<>(menuItems));

// create and assign the button renderer. we'll change the button renderer's emoji in the callback below
final EmojiFlyoutMenu.ButtonRenderer renderer = new EmojiFlyoutMenu.ButtonRenderer(emojiCodes[0], fontSizeInButton, color);
smileyFlyoutMenu.setButtonRenderer(renderer);

smileyFlyoutMenu.setSelectionListener(new FlyoutMenuView.SelectionListener() {
    @Override
    public void onItemSelected(FlyoutMenuView flyoutMenuView, FlyoutMenuView.MenuItem item) {

        // user has selected an item. update the button renderer's emoji to match
        renderer.setEmojiCode(((EmojiFlyoutMenu.MenuItem) item).getEmojiCode());
    }

    @Override
    public void onDismissWithoutSelection(FlyoutMenuView flyoutMenuView) {
    }
});