把下面腳本直接綁定在按鈕上，當按鈕點擊時就可以監聽到，這種方法不太好很不靈活。
void OnClick()
{
Debug.Log(“Button is Click!!!”);
}
方法二.使用SendMessage
選擇按鈕後，在Unity導航菜單欄中選擇Component->NGUI->Interaction->Button Message 組件。
Target：接收按鈕消息的遊戲對象。
Function Name：接收按鈕消息的方法，擁有這個方法的腳本必須綁定在上面Target對象身上。
Trigger：觸發的事件，OnClick顯然是一次點擊。
Include Children ：是否讓該對象的所有子對象也發送這個點擊事件。
到UIButtonMessage.cs這個腳本中看看，其實很簡單就是調用Unity自身的SendMessage而已。
void Send ()
{
if (string.IsNullOrEmpty(functionName)) return;
if (target == null) target = gameObject;
if (includeChildren)
{
Transform[] transforms = target.GetComponentsInChildren<Transform>();
for (int i = , imax = transforms.Length; i < imax; ++i)
{
Transform t = transforms[i];
t.gameObject.SendMessage(functionName, gameObject, SendMessageOptions.DontRequireReceiver);
}
}
else
{
target.SendMessage(functionName,
gameObject,
SendMessageOptions.DontRequireReceiver);
}
}
方法三.使用UIListener
這個也是推薦大家使用的一種方法，選擇按鈕後在Unity導航菜單欄中選擇Component->NGUI->Internal ->Event Listener。掛在按鈕上就可以，它沒有任何參數。
在任何一個腳本或者類中即可得到按鈕的點擊事件、把如下代碼放在任意類中或者腳本中。
void Awake ()
{
//獲取需要監聽的按鈕對象
GameObject button = GameObject.Find("UI Root (2D)/Camera/Anchor/Panel/LoadUI/MainCommon/Button");
//設置這個按鈕的監聽，指向本類的ButtonClick方法中。
UIEventListener.Get(button).onClick = ButtonClick;
}
//計算按鈕的點擊事件
void ButtonClick(GameObject button)
{
Debug.Log("GameObject " + button.name);
}
怎麼樣是不是很靈活？再看看它的源碼，使用的C#的代理，將UI的場景事件通過代理傳遞出去了。
public class UIEventListener : MonoBehaviour
{
public delegate void VoidDelegate (GameObject go);
public delegate void BoolDelegate (GameObject go, bool state);
public delegate void FloatDelegate (GameObject go, float delta);
public delegate void VectorDelegate (GameObject go, Vector
delta);
public delegate void StringDelegate (GameObject go, string text);
public delegate void ObjectDelegate (GameObject go, GameObject draggedObject);
public delegate void KeyCodeDelegate (GameObject go, KeyCode key);
public object parameter;
public VoidDelegate onSubmit;
public VoidDelegate onClick;
public VoidDelegate onDoubleClick;
public BoolDelegate onHover;
public BoolDelegate onPress;
public BoolDelegate onSelect;
public FloatDelegate onScroll;
public VectorDelegate onDrag;
public ObjectDelegate onDrop;
public StringDelegate onInput;
public KeyCodeDelegate onKey;
void OnSubmit () { if (onSubmit != null) onSubmit(gameObject); }
void OnClick () { if (onClick != null) onClick(gameObject); }
void OnDoubleClick () { if (onDoubleClick != null) onDoubleClick(gameObject); }
void OnHover (bool isOver) { if (onHover != null) onHover(gameObject, isOver); }
void OnPress (bool isPressed) { if (onPress != null) onPress(gameObject, isPressed); }
void OnSelect (bool selected) { if (onSelect != null) onSelect(gameObject,
selected); }
void OnScroll (float delta) { if (onScroll != null) onScroll(gameObject, delta); }
void OnDrag (Vector
delta)
{ if (onDrag != null) onDrag(gameObject, delta); }
void OnDrop (GameObject go) { if (onDrop != null) onDrop(gameObject, go); }
void OnInput (string text) { if (onInput != null) onInput(gameObject, text); }
void OnKey (KeyCode key) { if (onKey != null) onKey(gameObject, key); }
/// <summary>
/// Get or add
an event listener to the specified
game
object.
/// </summary>
static public UIEventListener Get (GameObject go)
{
UIEventListener listener = go.GetComponent<UIEventListener>();
if (listener == null) listener = go.AddComponent<UIEventListener>();
return listener;
}
}