var preloaded = [];
for (var i = 1; i <= 8; i++) {
  preloaded[i] = [loadImage("m"+i + "_0.png"), loadImage("m"+i + "_1.png")];
}

function init() {
  if (mtDropDown.isSupported()) {
    mtDropDown.initialize();
    m1.onactivate = function() { swapImage("button1", preloaded[1][1].src) };
    m1.ondeactivate = function() { swapImage("button1", preloaded[1][0].src) };
    
    m2.onactivate = function() { swapImage("button2", preloaded[2][1].src) };
    m2.ondeactivate = function() { swapImage("button2", preloaded[2][0].src) };

    m3.onactivate = function() { swapImage("button3", preloaded[3][1].src) };
    m3.ondeactivate = function() { swapImage("button3", preloaded[3][0].src) };

    m4.onactivate = function() { swapImage("button4", preloaded[4][1].src) };
    m4.ondeactivate = function() { swapImage("button4", preloaded[4][0].src) };

    m5.onactivate = function() { swapImage("button5", preloaded[5][1].src) };
    m5.ondeactivate = function() { swapImage("button5", preloaded[5][0].src) };
    
    m6.onactivate = function() { swapImage("button6", preloaded[6][1].src) };
    m6.ondeactivate = function() { swapImage("button6", preloaded[6][0].src) };
        
    m7.onactivate = function() { swapImage("button7", preloaded[7][1].src) };
    m7.ondeactivate = function() { swapImage("button7", preloaded[7][0].src) };
     
    m8.onactivate = function() { swapImage("button8", preloaded[8][1].src) };
    m8.ondeactivate = function() { swapImage("button8", preloaded[8][0].src) };
     
  }
}

function loadImage(sFilename) {
  var img = new Image();
  img.src ="/_w/images/" + sFilename;
  return img;
}

function swapImage(imgName, sFilename) {
  document.images[imgName].src = sFilename;
}