public override void OnInspectorGUI() { base.OnInspectorGUI(); TextHistory history = target as TextHistory; GUILayout.BeginHorizontal(); sampleText = GUILayout.TextField(sampleText); if (GUILayout.Button("Push")) { if (!string.IsNullOrEmpty(sampleText)) { history.PushText(sampleText); } } GUILayout.EndHorizontal(); if (GUILayout.Button("Clean")) { history.Clear(); } }