Cocos2d-x 没有移动时调用 onTouchMoved

Question

我正在编写一个 cocos2d-x 3.71 跨平台应用程序（ios、android、windows10），但我在实现触摸和按住时遇到了问题仅在 Android 上检测（ios 和 windows 工作正常）。我已经将其原因归结为这样一个事实，即当按住触摸而不移动时，onTouchMoved() 不断发射。我已经合并了一个解决方法，但这似乎是一个错误，我想知道是否有人有任何想法。

我在基于 cocos2d-x HelloWorld 示例的最小应用程序中重现了该问题。我只是从 cocos2d::Node (testNode) 派生了一个 class 并创建了它，并将其作为子项添加到 HelloWorldScene。在 testNode 中，我重写了更新函数并使用来自 onTouchBegan() 的 scheduleUpdate() 对其进行调度。在 update() 函数中，我简单地计算时间直到达到 0.25s，然后使用 unscheduleUpdate() 禁用更新。我在 onTouchMoved() 中有另一个 unscheduleUpdate() 调用以停止计算保持时间以防触摸移动。问题是，在 Android 上，onTouchMoved() 在触摸静止时开始不断触发。

testNode.h: 
#pragma once
#include "cocos2d.h"

class testNode : public cocos2d::Node
{
public:
    testNode() {}
    ~testNode() {}
    CREATE_FUNC(testNode);

    virtual bool init();
    virtual void update(float dt);

    bool onTouchBegan(cocos2d::Touch*, cocos2d::Event*);
    void onTouchMoved(cocos2d::Touch*, cocos2d::Event*);
    void onTouchEnded(cocos2d::Touch*, cocos2d::Event*);
    void onTouchCancelled(cocos2d::Touch*, cocos2d::Event*);

private:
    cocos2d::DrawNode* d;
    int id;
    bool touchIsDown;
    float touchTime;
    cocos2d::Label *messageLabel;
    cocos2d::Vec2 center;
};

testNode.cpp:

#include "testNode.h"
USING_NS_CC;

bool testNode::init()
{

    if (!Node::init())
    {
        return false;
    }
    setContentSize(Size(50, 50));

    Size size = Director::getInstance()->getWinSize();
    Size visibleSize = Director::getInstance()->getVisibleSize();
    setPosition(Vec2(size.width / 2.0f, size.height / 2.0f));
    center.x = size.width / 2.0f;
    center.y = size.height / 2.0f;

    d = DrawNode::create();
    addChild(d, 10);
    d->drawCircle(Vec2(0, 0), 50, (float)M_PI * 2, 50, false, Color4F::RED);

    auto touchListener = EventListenerTouchOneByOne::create();
    touchListener->setSwallowTouches(true);
    touchListener->onTouchBegan = CC_CALLBACK_2(testNode::onTouchBegan, this);
    touchListener->onTouchEnded = CC_CALLBACK_2(testNode::onTouchEnded, this);
    touchListener->onTouchMoved = CC_CALLBACK_2(testNode::onTouchMoved, this);
    touchListener->onTouchCancelled = CC_CALLBACK_2(testNode::onTouchCancelled, this);

    _eventDispatcher->addEventListenerWithSceneGraphPriority(touchListener, this);

    messageLabel = Label::createWithTTF("Hello World", "fonts/Marker Felt.ttf", 18);

    Vec2 origin = Director::getInstance()->getVisibleOrigin();
    messageLabel->setPosition(Vec2(0,0));
    addChild(messageLabel, 1);
    return true;
}

void testNode::update(float deltaTime)
{
    // When update is scheduled with scheduleUpdate(), this will increment the touchtimer
    // used for differenciating different touch actions.
    if (touchIsDown)
    {
        touchTime += deltaTime;
        if (touchTime > 0.25)
        {
            unscheduleUpdate();
        }
    }
}

bool testNode::onTouchBegan(Touch* touch, Event* event)
{
    Vec2 touchPoint = touch->getLocation();
    float startDistFromCenter = center.getDistance(touchPoint);
    touchTime = 0.0f;

    // Handle touch only if inside the radius of the circle
    if (startDistFromCenter <= 50)
    {
        // Track how long the touch is held without moving or releasing
        touchIsDown = true;
        scheduleUpdate();
        return true;
    }
    else
        return false;
}
void testNode::onTouchMoved(Touch* touch, Event* event)
{
    Vec2 pos = touch->getLocation();
    log("moving...pos = %f , %f", pos.x, pos.y);
    touchIsDown = false;
    unscheduleUpdate();
}
void testNode::onTouchEnded(Touch* touch, Event* event)
{
    touchIsDown = false;
    unscheduleUpdate();

    log("Hold Time: %f", touchTime);
}

void testNode::onTouchCancelled(Touch* touch, Event* event)
{
}

touch/hold 事件的典型输出：

09-23 23:42:39.852: D/cocos2d-x debug info(32508): startDistFromCenter: 33.753014 09-23 23:42:39.902: D/cocos2d-x debug info(32508): moving...pos = 246.732849 , 126.925316 09-23 23:42:39.902: D/cocos2d-x debug info(32508): moving...pos = 246.732849 , 126.925316 09-23 23:42:39.920: D/cocos2d-x debug info(32508): moving...pos = 246.732849 , 126.925316 09-23 23:42:39.935: D/cocos2d-x debug info(32508): moving...pos = 246.732849 , 126.925316 09-23 23:42:39.969: D/cocos2d-x debug info(32508): moving...pos = 246.732849 , 126.925316 09-23 23:42:39.969: D/cocos2d-x debug info(32508): moving...pos = 246.732849 , 126.925316 09-23 23:42:39.989: D/cocos2d-x debug info(32508): moving...pos = 246.732849 , 126.925316 09-23 23:42:39.999: D/cocos2d-x debug info(32508): moving...pos = 246.732849 , 126.925316 09-23 23:42:40.027: D/cocos2d-x debug info(32508): moving...pos = 246.732849 , 126.925316 09-23 23:42:40.043: D/cocos2d-x debug info(32508): moving...pos = 246.732849 , 126.925316 09-23 23:42:40.043: D/cocos2d-x debug info(32508): Hold Time: 0.042597

如您所见，该位置并未实际移动....给出了什么？

作为参考，我正在 Windows 10、Visual Studio 2015、cocos2d-x 3.71 上开发，并在 Android 5.1.1 上进行测试（OnePlusOne phone)

Answer 1

我测试了你的代码，这个问题与 android lollipop 有关。在 kitkat 上一切正常（测试设备 Huawei Ascend P7 android 4.4.2）：

09-24 11:51:25.351: D/cocos2d-x debug info(1058): Hold Time: 0.252129
09-24 11:51:27.361: D/cocos2d-x debug info(1058): Hold Time: 0.251298
09-24 11:51:28.711: D/cocos2d-x debug info(1058): Hold Time: 0.252115
09-24 11:51:30.101: D/cocos2d-x debug info(1058): Hold Time: 0.251961

我也在棒棒糖设备上试过（LG，但我不记得确切的型号），就像你说的那样。触摸的垃圾邮件移动到相同的位置。

作为解决方法，您可以像 Alex G 所说的那样做，或者记住最后一个位置（在触摸开始时记住它）并忽略具有完全相同位置的事件。

顺便说一句，我正在使用 Mac OS X Yosemite 和 Cocos2d-x 3.8.

您应该在 cocos2d-x github 页面上开始一个问题。

Cocos2d-x 没有移动时调用 onTouchMoved

Cocos2d-x onTouchMoved called when no movement is occurring

c++

android

cocos2d-x

cocos2d-android

cocos2d-x-3.0