var dropdown_id = 0;
var mouseover_id = 0;
var disable_hide = false;
function display_dropdown_navi(id) {
  var html_object = null;
  
  if(dropdown_id > 0) {
    hide_dropdown_navi(true);
  }
  
  if(id) {
    dropdown_id = id;
    disable_hide = true;
    
    object_id = 'dropdownnavi' + dropdown_id;
    dobject = null;
    
    if(document.getElementById) {
      dobject = document.getElementById(object_id);
    } else if(document.all) {
      dobject = document.all[object_id];
    }
    if(dobject) {
      dobject.style.display = 'block';
    } else {
      
    }
  }
}

function hide_dropdown_navi(force) {
  object_id = 'dropdownnavi' + dropdown_id;
  var dobject = null;
  if(document.getElementById) {
    dobject = document.getElementById(object_id);
  } else if(document.all) {
    dobject = document.all[object_id];
  }
  if(dobject) {
    if(disable_hide != true || force == true) {
      dobject.style.display = 'none';
      dropdown_id = 0;
      disable_hide = false;
    }
  }
}

function set_hide(mode) {
  disable_hide = mode;
}

function display_bookmarks(id) {
  var dobject = null;
  if(document.getElementById) {
    dobject = document.getElementById(id);
  } else if(document.all) {
    dobject = document.all[id];
  }
  if(dobject) {
    if(dobject.style.display=='none') {
      dobject.style.display = 'block';
    } else {
      dobject.style.display = 'none';
    }
  }
}