为什么触摸屏幕时性能会提高？

Question

由于某些原因，当我按住鼠标左键在屏幕上（模拟器上）四处移动时，FPS会大幅跳升。 通常我的游戏很慢，但是如果我触摸屏幕（并且只要我在触摸时四处移动鼠标），它就会非常流畅。

我曾尝试在onTouchEvent中睡眠20毫秒，但似乎没有任何区别。

这是我在onTouchEvent中使用的代码：

 // events when touching the screen
    public boolean onTouchEvent(MotionEvent event) 
    {
        int eventaction = event.getAction(); 

        touchX=event.getX();
        touchY=event.getY();

        switch (eventaction) 
        { 
         case MotionEvent.ACTION_DOWN: 
         {
          touch=true;
         }
         break; 

         case MotionEvent.ACTION_MOVE:
         {

         }
         break; 

         case MotionEvent.ACTION_UP: 

         {
          touch=false;
         }
              break; 
        }

     /*try 
     {
      AscentThread.sleep(20);
     } 
     catch (InterruptedException e) 
     {
      // TODO Auto-generated catch block
      e.printStackTrace();
     }*/

        return true; 
    }

在logcat日志中，FPS是当前fps（最近20帧的平均值），touch是是否正在触摸屏幕（来自onTouchEvent）。

到底是怎么回事？ 以前有没有其他人有这种奇怪的行为？

Logcat日志：

12-21 19:43:26.154: INFO/myActivity(786): FPS: 31.686569159606414 Touch: false
12-21 19:43:27.624: INFO/myActivity(786): FPS: 19.46310293212206 Touch: false
12-21 19:43:29.104: INFO/myActivity(786): FPS: 18.801202175690467 Touch: false
12-21 19:43:30.514: INFO/myActivity(786): FPS: 21.118295877408478 Touch: false
12-21 19:43:31.985: INFO/myActivity(786): FPS: 19.117397812958878 Touch: false
12-21 19:43:33.534: INFO/myActivity(786): FPS: 15.572571858239263 Touch: false
12-21 19:43:34.934: INFO/myActivity(786): FPS: 20.584119901503506 Touch: false
12-21 19:43:36.404: INFO/myActivity(786): FPS: 18.888025905454207 Touch: false
12-21 19:43:37.814: INFO/myActivity(786): FPS: 22.35722329083629 Touch: false
12-21 19:43:39.353: INFO/myActivity(786): FPS: 15.73604859775362 Touch: false
12-21 19:43:40.763: INFO/myActivity(786): FPS: 20.912449882754633 Touch: false
12-21 19:43:42.233: INFO/myActivity(786): FPS: 18.785278388997718 Touch: false
12-21 19:43:43.634: INFO/myActivity(786): FPS: 20.1357397209596 Touch: false
12-21 19:43:45.043: INFO/myActivity(786): FPS: 21.961138432007957 Touch: false
12-21 19:43:46.453: INFO/myActivity(786): FPS: 22.167196852834273 Touch: false
12-21 19:43:47.854: INFO/myActivity(786): FPS: 22.207318228024274 Touch: false
12-21 19:43:49.264: INFO/myActivity(786): FPS: 22.36980559230175 Touch: false
12-21 19:43:50.604: INFO/myActivity(786): FPS: 23.587638823252547 Touch: false
12-21 19:43:52.073: INFO/myActivity(786): FPS: 19.233902040593076 Touch: false
12-21 19:43:53.624: INFO/myActivity(786): FPS: 15.542190150440987 Touch: false
12-21 19:43:55.034: INFO/myActivity(786): FPS: 20.82290063974675 Touch: false
12-21 19:43:56.436: INFO/myActivity(786): FPS: 21.975282007207717 Touch: false
12-21 19:43:57.914: INFO/myActivity(786): FPS: 18.786927284103687 Touch: false
12-21 19:43:59.393: INFO/myActivity(786): FPS: 18.96879004217992 Touch: false
12-21 19:44:00.625: INFO/myActivity(786): FPS: 28.367566618064878 Touch: false
12-21 19:44:02.113: INFO/myActivity(786): FPS: 19.04441528684418 Touch: false
12-21 19:44:03.585: INFO/myActivity(786): FPS: 18.807837511809065 Touch: false
12-21 19:44:04.993: INFO/myActivity(786): FPS: 21.134330284993418 Touch: false
12-21 19:44:06.275: INFO/myActivity(786): FPS: 27.209688764079907 Touch: false
12-21 19:44:07.753: INFO/myActivity(786): FPS: 19.055894653261653 Touch: false
12-21 19:44:09.163: INFO/myActivity(786): FPS: 22.05422794901088 Touch: false
12-21 19:44:10.644: INFO/myActivity(786): FPS: 18.6956805300596 Touch: false
12-21 19:44:12.124: INFO/myActivity(786): FPS: 17.434180581311054 Touch: false
12-21 19:44:13.594: INFO/myActivity(786): FPS: 18.71932038510891 Touch: false
12-21 19:44:14.504: INFO/myActivity(786): FPS: 40.94571503868066 Touch: true
12-21 19:44:14.924: INFO/myActivity(786): FPS: 57.061200121138576 Touch: true
12-21 19:44:15.364: INFO/myActivity(786): FPS: 62.54377946377936 Touch: true
12-21 19:44:15.764: INFO/myActivity(786): FPS: 64.05005071818726 Touch: true
12-21 19:44:16.384: INFO/myActivity(786): FPS: 50.912951172948155 Touch: true
12-21 19:44:16.874: INFO/myActivity(786): FPS: 55.31242053078078 Touch: true
12-21 19:44:17.364: INFO/myActivity(786): FPS: 59.31625410615102 Touch: true
12-21 19:44:18.413: INFO/myActivity(786): FPS: 36.63504170925923 Touch: false
12-21 19:44:19.885: INFO/myActivity(786): FPS: 18.099130467755923 Touch: false
12-21 19:44:21.363: INFO/myActivity(786): FPS: 18.458978222946566 Touch: false
12-21 19:44:22.683: INFO/myActivity(786): FPS: 25.582179409330823 Touch: true
12-21 19:44:23.044: INFO/myActivity(786): FPS: 60.99865521942455 Touch: true
12-21 19:44:23.403: INFO/myActivity(786): FPS: 74.17873975470984 Touch: true
12-21 19:44:23.763: INFO/myActivity(786): FPS: 64.25663040460714 Touch: true
12-21 19:44:24.113: INFO/myActivity(786): FPS: 62.47483457826921 Touch: true
12-21 19:44:24.473: INFO/myActivity(786): FPS: 65.27969529547072 Touch: true
12-21 19:44:24.825: INFO/myActivity(786): FPS: 67.84743115273311 Touch: true
12-21 19:44:25.173: INFO/myActivity(786): FPS: 73.50854551357706 Touch: true
12-21 19:44:25.523: INFO/myActivity(786): FPS: 70.46432534585368 Touch: true
12-21 19:44:25.873: INFO/myActivity(786): FPS: 69.04076953445896 Touch: true

Answer 1

如果您在Windows上运行模拟器，那么我认为这可以解释一下：

Windows中的性能选项说明

...另外，请记住，Microsoft Windows NT还基于其他事件使用其他优先级调整（通常为2），例如从I / O调用返回时，从用户模式子系统调用返回时，暂时提高线程的优先级。 ，或接收键盘输入时。

我已经多次看到这种效果。 我只是使用ProcessExplorer窥视了模拟器：虽然我不能肯定地说，但是看起来模拟器运行在单个Windows线程下。 除非您在真正的Android设备上看到类似的性能提升，否则我认为这是Windows操作系统而不是AndroidOS的影响。

Answer 2

我遇到了同样的问题，即使不太明显，它也出现在电话上。 我想我知道发生了什么。 我在主循环中使用了带有postDelayed（...）的处理程序。 我想绘图首先会以某种方式阻塞消息队列，然后touchevent会使应用在下一次计划检查之前检查队列。 为什么问题在某种程度上随机发生是一个谜。

我通过将postDelayed-line放置在Runnable中的图形之前来解决它。

当然，它与Windows没有任何关系。