在Processing中创建视频键盘，我有重叠的循环

Question

我不知道为什么我无法让我的视频键盘工作。我编写了我的代码，这样当你按任意键时，Processing会播放从数组中随机选择的视频。

//forum.processing.org/two/discussion/6590/play-a-random-list-of-videos-by-keypress-exhaust

boolean sketchFullScreen() {
  return true;
}

import processing.video.*;
String[] moviesNames = { 
  "1.mov", "2.mov", "3.mov", "4.mov","5.mov", "6.mov", "7.mov","8.mov", "9.mov", "10.mov","11.mov", 
  "12.mov", "13.mov","14.mov", "15.mov", "16.mov","17.mov", "18.mov", "19.mov","20.mov", "21.mov", "22.mov","23.mov","24.mov", "25.mov", "26.mov",
};
int index = int(random(moviesNames.length));

Movie[] movies;

//Movie mov_a, mov_b, mov_c, mov_d, nowPlaying;

Boolean isPlaying = false;

void setup() {
  size(displayWidth, displayHeight, P2D);
  background(0);
  frameRate = 60;
  movies = new Movie[moviesNames.length];
  for (int i = 0; i < moviesNames.length; i++) {
    movies[i] = new Movie(this, moviesNames[i]); 
  }
}

void draw() {
  background(0);

  if(isPlaying){
    image(movies[index], 0, 0, width, height);

  }
}


void movieEvent(Movie _mov) {
  _mov.read();
}

void keyPressed() {

  isPlaying = true;
  int k = keyCode;
  if (k >= 'A' && k <= 'Z'){
    pickRandomVideoIndex();
  }
}

void keyReleased(){
  isPlaying = false;
  movies[index].stop();
}


void pickRandomVideoIndex() {
  if (movies.length <= 1) {
    return;
  }
  //movies[index].pause(); // pause current video.

  int rnd = index; // keep picking a new index till got a diff. 1:
  while ( rnd == index ){
   rnd = (int) random(movies.length);
  }

  // assign newly picked random value to index:
  index = rnd;
  movies[index].loop(); // and start playing it.
}

在按下多个按键时，我非常乐意帮助确定如何防止视频互相播放。一旦你按下一个以上的键，或者输入的速度非常快，那么一切都会崩溃。

谢谢，here are my files。