class Scrollbar{
  int x, y;
  float sw, sh;
  float pos;
  float posMin, posMax;
  boolean rollover;
  boolean locked;
  float minVal;
  float maxVal;
  color backgroundColor;  
  color frontColor;
  color overColor;
  color clicC;
  String label;
  
  Scrollbar(int xp, int yp, int w, int h, float miv, float mav, String _l, color _bc, color _fc, color _oc){
    x = xp;
    y = yp;
    sw = w;
    sh = h;
    minVal = miv;
    maxVal = mav;
    pos = 40;
    posMin = y+sh-sh;
    posMax = y;
    label = _l;
    backgroundColor = _bc;
    frontColor = _fc;
    overColor = _oc;
  }
  
  void update(int mx, int my){
    if(over(mx, my) == true){
      rollover = true;
    }else{
      rollover = false;
    }
    if(locked == true){
      pos = -1*(constrain(-1*(y+sh-mouseY), -1*sh, 0));
//      pos = -1*(y+sh-mouseY);
    }
    
  }
  
  void press(int mx, int my){
    if(rollover==true){
      locked = true;
    }else{
      locked = false;
    }
  }
  
  void release(){
    locked = false;
  }
  
  boolean over(int mx, int my){
    if((mx > x) && (mx < x+sw) && (my > y) && (my < y+sh)){
      return true;
    }else{
      return false;
    }
  }
  
  void display(){
    fill(backgroundColor);
    rect(x, y, sw, sh);  //  white background.
    if((rollover==true) || (locked==true)){
      fill(overColor);
    }else{
      fill(frontColor);
    }
    rect(x, y+sh, sw,-pos);  //  clicked rectangle
    float oe = y+sh;
  }
  
  float getPos(){
    float offset = map(pos, 0, sh, minVal, maxVal);
    return offset;
  }
  
  void displayText(){
    if((rollover==true) || (locked==true)){
      fill(overColor);
    }else{
      fill(frontColor);
    }
    textFont(font, 14);
    textAlign(CENTER);
    text(round(getPos()), x+(sw/2), (y+sh)-pos);
    text(label, x+(sw/2), y+sh+15);
  }
}