cocos2dx-lua捕获用户touch事件的几种方式？

这里只针对lua

1.为每个关心的事件注册回调函数

具体分为以下几种

1>单点触摸

注册函数为

cc.Handler.EVENT_TOUCH_BEGAN = 40

cc.Handler.EVENT_TOUCH_MOVED = 41

cc.Handler.EVENT_TOUCH_ENDED = 42

cc.Handler.EVENT_TOUCH_CANCELLED = 43

注册的时候必须通过

cc.EventListenerTouchOneByOne:create() 创建listener

onTouchBegin/onTouchMove/onTouchEnd为自己注册的回调函数

代码如下:

local listener = cc.EventListenerTouchOneByOne:create();

listener:registerScriptHandler(onTouchBegin,cc.Handler.EVENT_TOUCH_BEGAN);

listener:registerScriptHandler(onTouchMove,cc.Handler.EVENT_TOUCH_MOVED);

listener:registerScriptHandler(onTouchEnd,cc.Handler.EVENT_TOUCH_ENDED);

2>多点点触摸

cc.Handler.EVENT_TOUCHES_BEGAN = 44

cc.Handler.EVENT_TOUCHES_MOVED = 45

cc.Handler.EVENT_TOUCHES_ENDED = 46

cc.Handler.EVENT_TOUCHES_CANCELLED = 47

注册的时候必须通过

cc.EventListenerTouchAllAtOnce:create() 创建listener

onTouchesBegin/onTouchesMove/onTouchesEnd为自己注册的回调函数

代码如下:

local listener = cc.EventListenerTouchAllAtOnce:create();

listener:registerScriptHandler(onTouchesBegin,cc.Handler.EVENT_TOUCHES_BEGAN);

listener:registerScriptHandler(onTouchesMove,cc.Handler.EVENT_TOUCHES_MOVED);

listener:registerScriptHandler(onTouchesEnd,cc.Handler.EVENT_TOUCHES_ENDED);

最后通过下面的代码绑定listener

cc.Director:getInstance():getEventDispatcher():addEventListenerWithSceneGraphPriority(listener,_layer);

其中_layer是要需要事件的对象

前面 cc.Director:getInstance() 也可用换成_layer 或者 _layer的父节点的对象

这里有几点需要注意:

1.onTouchesBegin/onTouchBegin 里面需要 return true,表示需要处理这个事件,不然不会掉用onTouchMove/onTouchEnd

2.每个触摸函数都包含2个参数 以onTouchMove为例:

local function onTouchMove(touch,event)

end

touch / event 都是userdata(可以理解为C/LUA共有的数据 只要实现了对应的方法 C/Lua可以直接访问/赋值/调用函数 由C管理这块内存)

touch 是当前的触摸点 以下是它的方法

/** Returns the current touch location in OpenGL coordinates.

*

* @return The current touch location in OpenGL coordinates.

*/

Vec2 getLocation() const;

/** Returns the previous touch location in OpenGL coordinates.

*

* @return The previous touch location in OpenGL coordinates.

*/

Vec2 getPreviousLocation() const;

/** Returns the start touch location in OpenGL coordinates.

*

* @return The start touch location in OpenGL coordinates.

*/

Vec2 getStartLocation() const;

/** Returns the delta of 2 current touches locations in screen coordinates.

*

* @return The delta of 2 current touches locations in screen coordinates.

*/

Vec2 getDelta() const;

/** Returns the current touch location in screen coordinates.

*

* @return The current touch location in screen coordinates.

*/

Vec2 getLocationInView() const;

/** Returns the previous touch location in screen coordinates.

*

* @return The previous touch location in screen coordinates.

*/

Vec2 getPreviousLocationInView() const;

/** Returns the start touch location in screen coordinates.

*

* @return The start touch location in screen coordinates.

*/

如下面的代码可以在onTouchMove中直接获取 用户手指的移动距离

local dis = touch:getDelta()

print(dis.x,dis.y);

如果是多点触摸 touch是一个table

touch[1] touch[2] touch[3]…是触摸的对应点

event 可以表明表明

1.当前用户点击了那个object (event:getCurrentTarget())

2.当前是press/move/release的那个状态 (event:getEventCode())

cc.EventCode =

{

BEGAN = 0,

MOVED = 1,

ENDED = 2,

CANCELLED = 3,

}

所以我们可以通过一个回调函数来判断当前是那个操作 而不用写3个函数

示例代码

local function onTouchBegin(touch,event)

local p = touch:getLocation();

p = _layer:convertToNodeSpace(p);

print(p.x,p.y)

return true;

end

local function onTouchMove(touch,event)

end

local function onTouchEnd(touch,event)

end

local function onTouchesBegin(touch,event)

return true;

end

local function onTouchesMove(touch,event)

for i = 1,table.getn(touch) do

local location = touch[i]:getLocation()

print(i,location.x,location.y)

end

end

local function onTouchesEnd(touch,event)

print("onTouchesEnd");

end

_layer = cc.Layer:create();

_layer:setTouchEnabled(true)

local listener1 = cc.EventListenerTouchOneByOne:create();

listener1:registerScriptHandler(onTouchBegin,cc.Handler.EVENT_TOUCH_BEGAN);

listener1:registerScriptHandler(onTouchMove,cc.Handler.EVENT_TOUCH_MOVED);

listener1:registerScriptHandler(onTouchEnd,cc.Handler.EVENT_TOUCH_ENDED);

--多点触摸

-- local listener2 = cc.EventListenerTouchAllAtOnce:create()

--listener2:registerScriptHandler(onTouchesBegin,cc.Handler.EVENT_TOUCHES_BEGAN )

-- listener2:registerScriptHandler(onTouchesMove,cc.Handler.EVENT_TOUCHES_MOVED )

-- listener2:registerScriptHandler(onTouchesEnd,cc.Handler.EVENT_TOUCHES_MOVED )

local eventDispatcher = _layer:getEventDispatcher()

eventDispatcher:addEventListenerWithSceneGraphPriority(listener1, _layer)

--eventDispatcher:addEventListenerWithSceneGraphPriority(listener2, _layer)

2.直接看代码

local function onTouchEvent(state , ... )

local args = {...};

print(state);

for k,v in pairs(args[1]) do

print(k,v)

end

end

_layer:registerScriptTouchHandler(onTouchEvent,true,0,false);

@onTouchEvent 回调

@ture表示捕获要捕获多点触摸

@0优先级

@false 是否吞没触摸事件

如果是单点触摸 args[1] ->x,y,id

如果是多点触摸 args[1] ->x1,y1,id1,x2,y2,id2

这里cocos2dx-lua封装了 Layer:onTouch(callback, isMultiTouches, swallowTouches)

建议直接使用

这里如果你用cocos2dx-lua 的 lua-empty-test 做模板建立工程 有个bug

需要在 didFinishLaunchingWithOptions 添加代码

[eaglView setMultipleTouchEnabled:YES];

来打开多点触摸