How do I put a button in a VLC player

See more:

C++/CLI

I am making a media player using VLC. I designed a winform in c# project and using P/invoke to use the function "libvlc_media_player_set_hwnd". The media could be played. But it could not be seen that the butten I put in the player. I would like there is a butten. What should I do?

Here is my code.

 public Form1()
 {
     InitializeComponent();
     int res = VLC.VLC_load(Player.Handle);
 }
 private void button1_Click(object sender, EventArgs e)
 {
 int res = VLC.VLC_play("D:\\tmp2\\3.rmvb");
 }


public static class VLC
	{
		[DllImport("MagicPlayer.dll")]
		public extern static int VLC_load(IntPtr window);

		[DllImport("MagicPlayer.dll")]
        public extern static int VLC_go_back_to_last_stop();

		[DllImport("MagicPlayer.dll")]
        public extern static int VLC_pause();

		[DllImport("MagicPlayer.dll")]
        public extern static int VLC_play(string fileName);
        
        [DllImport("MagicPlayer.dll")]
        public extern static int VLC_release();
	}

It can run. But when I put the butten into the the Player which is a panal. It can't be seen.