JS CSS drop-down menu background problem_html/css_WEB-ITnose
Jun 24, 2016 pm 12:22 PM
select scroll bar
The following code changes the style of the drop-down menu and can be used normally. However, there is a problem now that there is a lot of content in the drop-down menu. I think there will be a scroll bar automatically at a certain height. Could anyone help me please, thank you very much.
<script language="JavaScript" type="text/javascript">var selects = document.getElementsByTagName('select');var isIE = (document.all && window.ActiveXObject && !window.opera) ? true : false;function $(id) { return document.getElementById(id);}function stopBubbling (ev) { ev.stopPropagation();}function rSelects() { for (i=0;i<selects.length;i++){ selects[i].style.display = 'none'; select_tag = document.createElement('div'); select_tag.id = 'select_' + selects[i].name; select_tag.className = 'select_box'; selects[i].parentNode.insertBefore(select_tag,selects[i]); select_info = document.createElement('div'); select_info.id = 'select_info_' + selects[i].name; select_info.className='tag_select'; select_info.style.cursor='pointer'; select_tag.appendChild(select_info); select_ul = document.createElement('ul'); select_ul.id = 'options_' + selects[i].name; select_ul.className = 'tag_options'; select_ul.style.position='absolute'; select_ul.style.display='none'; select_ul.style.zIndex='999'; select_tag.appendChild(select_ul); rOptions(i,selects[i].name); mouseSelects(selects[i].name); if (isIE){ selects[i].onclick = new Function("clickLabels3('"+selects[i].name+"');window.event.cancelBubble = true;"); } else if(!isIE){ selects[i].onclick = new Function("clickLabels3('"+selects[i].name+"')"); selects[i].addEventListener("click", stopBubbling, false); } }}function rOptions(i, name) { var options = selects[i].getElementsByTagName('option'); var options_ul = 'options_' + name; for (n=0;n<selects[i].options.length;n++){ option_li = document.createElement('li'); option_li.style.cursor='pointer'; option_li.className='open'; $(options_ul).appendChild(option_li); option_text = document.createTextNode(selects[i].options[n].text); option_li.appendChild(option_text); option_selected = selects[i].options[n].selected; if(option_selected){ option_li.className='open_selected'; option_li.id='selected_' + name; $('select_info_' + name).appendChild(document.createTextNode(option_li.innerHTML)); } option_li.onmouseover = function(){ this.className='open_hover';} option_li.onmouseout = function(){ if(this.id=='selected_' + name){ this.className='open_selected'; } else { this.className='open'; } } option_li.onclick = new Function("clickOptions("+i+","+n+",'"+selects[i].name+"')"); }}function mouseSelects(name){ var sincn = 'select_info_' + name; $(sincn).onmouseover = function(){ if(this.className=='tag_select') this.className='tag_select_hover'; } $(sincn).onmouseout = function(){ if(this.className=='tag_select_hover') this.className='tag_select'; } if (isIE){ $(sincn).onclick = new Function("clickSelects('"+name+"');window.event.cancelBubble = true;"); } else if(!isIE){ $(sincn).onclick = new Function("clickSelects('"+name+"');"); $('select_info_' +name).addEventListener("click", stopBubbling, false); }}function clickSelects(name){ var sincn = 'select_info_' + name; var sinul = 'options_' + name; for (i=0;i<selects.length;i++){ if(selects[i].name == name){ if( $(sincn).className =='tag_select_hover'){ $(sincn).className ='tag_select_open'; $(sinul).style.display = ''; } else if( $(sincn).className =='tag_select_open'){ $(sincn).className = 'tag_select_hover'; $(sinul).style.display = 'none'; } } else{ $('select_info_' + selects[i].name).className = 'tag_select'; $('options_' + selects[i].name).style.display = 'none'; } }}function clickOptions(i, n, name){ var li = $('options_' + name).getElementsByTagName('li'); $('selected_' + name).className='open'; $('selected_' + name).id=''; li[n].id='selected_' + name; li[n].className='open_hover'; $('select_' + name).removeChild($('select_info_' + name)); select_info = document.createElement('div'); select_info.id = 'select_info_' + name; select_info.className='tag_select'; select_info.style.cursor='pointer'; $('options_' + name).parentNode.insertBefore(select_info,$('options_' + name)); mouseSelects(name); $('select_info_' + name).appendChild(document.createTextNode(li[n].innerHTML)); $( 'options_' + name ).style.display = 'none' ; $( 'select_info_' + name ).className = 'tag_select'; selects[i].options[n].selected = 'selected';}window.onload = function(e) { bodyclick = document.getElementsByTagName('body').item(0); rSelects(); bodyclick.onclick = function(){ for (i=0;i<selects.length;i++){ $('select_info_' + selects[i].name).className = 'tag_select'; $('options_' + selects[i].name).style.display = 'none'; } }}</script> <style type="text/css">body{margin:0px; padding:0px; font-size:12px; color:#FFFFFB; background:#3d4045; }div,ul,li{margin:0; padding:0;}#macstyle1 .select_box{height:22px; width:271px;}#macstyle1 div.tag_select{display:block;color:#fff; text-align:left; padding-left:10px;width:271px;height:22px;background:url(http://img.bbs.csdn.net/upload/201307/03/1372819568_91197.gif) no-repeat;line-height:22px;}#macstyle1 div.tag_select_hover{display:block;color:#fff;text-align:left; padding-left:10px;width:271px;height:22px;background:url(http://img.bbs.csdn.net/upload/201307/03/1372819568_91197.gif) no-repeat;line-height:22px;}#macstyle1 div.tag_select_open{display:block;color:#fff;text-align:left; padding-left:10px;width:271px;height:22px;background:url(http://img.bbs.csdn.net/upload/201307/03/1372819568_91197.gif) no-repeat;line-height:22px;}#macstyle1 ul.tag_options{position:absolute;list-style:none;text-align:left; }#macstyle1 ul.tag_options li{ background:#414348;text-align:left; padding-left:10px;width:241px;height:15px;line-height:15px;color:#fff;overflow:auto;}#macstyle1 ul.tag_options li.open_hover{color:#fff; background:#6c6f75; }#macstyle1 ul.tag_options li.open_selected{color:#fff; }</style> <div id="macstyle1"> <select > <option value="GMT-12:00">GMT-12:00 日界線西</option> <option value="GMT-11:00">GMT-11:00 中途島，薩摩亞群島</option> <option value="GMT-10:00">GMT-10:00 夏威夷</option> <option value="GMT-9:00">GMT-9:00 阿拉斯加</option> <option value="GMT-8:00">GMT-8:00 太平洋時間(美國和加拿大)</option> <option value="GMT-7:00">GMT-7:00 山地時間(美國和加拿大)</option> <option value="GMT-6:00">GMT-6:00 中部時間(美國和加拿大)</option> <option value="GMT-5:00">GMT-5:00 東部時間(美國和加拿大)</option> <option value="GMT-4:30">GMT-4:30 加拉斯加</option> <option value="GMT-4:00">GMT-4:00 大西洋時間(加拿大)</option> <option value="GMT-3:30">GMT-3:30 紐芬蘭</option> <option value="GMT-3:00">GMT-3:00 喬治郭、巴西利亞</option> <option value="GMT-2:00">GMT-2:00 中大西洋</option> <option value="GMT-1:00">GMT-1:00 佛得角群島、亞速爾群島</option> <option value="GMT-0:00">GMT-0:00 都柏林、愛丁堡、倫敦</option> <option value="GMT+1:00">GMT+1:00 阿姆斯特丹、柏林、羅馬、巴黎</option> <option value="GMT+2:00">GMT+2:00 雅典、耶路撒冷、伊斯坦布爾</option> <option value="GMT+3:00">GMT+3:00 巴格達、科威特、莫斯科</option> <option value="GMT+3:30">GMT+3:30 德黑蘭</option> <option value="GMT+4:00">GMT+4:00 高加索標準時間</option> <option value="GMT+4:30">GMT+4:30 喀布爾</option> <option value="GMT+5:00">GMT+5:00 伊斯蘭堡、卡拉奇、塔什干</option> <option value="GMT+5:30">GMT+5:30 馬德拉斯、孟買、新德里</option> <option value="GMT+5:45">GMT+5:45 加德滿都</option> <option value="GMT+6:00">GMT+6:00 阿拉木圖、新西伯利亞、達卡</option> <option value="GMT+6:30">GMT+6:30 仰光</option> <option value="GMT+7:00">GMT+7:00 曼谷、河內(nèi)、雅加達</option> <option value="GMT+8:00" selected="selected">GMT+8:00 北京、烏魯木齊、新加坡</option> <option value="GMT+9:00">GMT+9:00 漢城、東京、大阪、札幌</option> <option value="GMT+9:30" >GMT+9:30 阿德萊德、達爾文</option> <option value="GMT+10:00" >GMT+10:00 墨爾本、悉尼、堪培拉</option> <option value="GMT+11:00">GMT+11:00 馬加丹、索羅門群島</option> <option value="GMT+12:00">GMT+12:00 奧克蘭、惠靈頓</option> <option value="GMT+13:00">GMT+13:00 努庫阿洛法</option> </select> </div>
Reply to discussion (solution)
The default overflow is visible. It will open automatically. Just give #macstyle1 ul.tag_options a suitable height and set overflow-y:auto;. For the sake of beauty, overflow-x can be set to hidden. After the scroll bar comes out, the width is a bit insufficient. It is recommended to add a little more.
<!doctype html><html><head><meta charset="utf-8" /><style type="text/css">body{margin:0px; padding:0px; font-size:12px; color:#FFFFFB; background:#3d4045; }div,ul,li{margin:0; padding:0;}#macstyle1 .select_box{height:22px; width:271px;}#macstyle1 div.tag_select{display:block;color:#fff; text-align:left; padding-left:10px;width:271px;height:22px;background:url(http://img.bbs.csdn.net/upload/201307/03/1372819568_91197.gif) no-repeat;line-height:22px;}#macstyle1 div.tag_select_hover{display:block;color:#fff;text-align:left; padding-left:10px;width:271px;height:22px;background:url(http://img.bbs.csdn.net/upload/201307/03/1372819568_91197.gif) no-repeat;line-height:22px;}#macstyle1 div.tag_select_open{display:block;color:#fff;text-align:left; padding-left:10px;width:271px;height:22px;background:url(http://img.bbs.csdn.net/upload/201307/03/1372819568_91197.gif) no-repeat;line-height:22px;}#macstyle1 ul.tag_options{position:absolute;list-style:none;text-align:left;height:300px;overflow-y:auto;overflow-x:hidden;}#macstyle1 ul.tag_options li{ background:#414348;text-align:left; padding-left:10px;width:241px;height:15px;line-height:15px;color:#fff;overflow:auto;}#macstyle1 ul.tag_options li.open_hover{color:#fff; background:#6c6f75; }#macstyle1 ul.tag_options li.open_selected{color:#fff; }</style><script language="JavaScript" type="text/javascript">var selects = document.getElementsByTagName('select'); var isIE = (document.all && window.ActiveXObject && !window.opera) ? true : false; function $(id) { return document.getElementById(id);} function stopBubbling (ev) { ev.stopPropagation();} function rSelects() { for (i=0;i<selects.length;i++){ selects[i].style.display = 'none'; select_tag = document.createElement('div'); select_tag.id = 'select_' + selects[i].name; select_tag.className = 'select_box'; selects[i].parentNode.insertBefore(select_tag,selects[i]); select_info = document.createElement('div'); select_info.id = 'select_info_' + selects[i].name; select_info.className='tag_select'; select_info.style.cursor='pointer'; select_tag.appendChild(select_info); select_ul = document.createElement('ul'); select_ul.id = 'options_' + selects[i].name; select_ul.className = 'tag_options'; select_ul.style.position='absolute'; select_ul.style.display='none'; select_ul.style.zIndex='999'; select_tag.appendChild(select_ul); rOptions(i,selects[i].name); mouseSelects(selects[i].name); if (isIE){ selects[i].onclick = new Function("clickLabels3('"+selects[i].name+"');window.event.cancelBubble = true;"); } else if(!isIE){ selects[i].onclick = new Function("clickLabels3('"+selects[i].name+"')"); selects[i].addEventListener("click", stopBubbling, false); } }} function rOptions(i, name) { var options = selects[i].getElementsByTagName('option'); var options_ul = 'options_' + name; for (n=0;n<selects[i].options.length;n++){ option_li = document.createElement('li'); option_li.style.cursor='pointer'; option_li.className='open'; $(options_ul).appendChild(option_li); option_text = document.createTextNode(selects[i].options[n].text); option_li.appendChild(option_text); option_selected = selects[i].options[n].selected; if(option_selected){ option_li.className='open_selected'; option_li.id='selected_' + name; $('select_info_' + name).appendChild(document.createTextNode(option_li.innerHTML)); } option_li.onmouseover = function(){ this.className='open_hover';} option_li.onmouseout = function(){ if(this.id=='selected_' + name){ this.className='open_selected'; } else { this.className='open'; } } option_li.onclick = new Function("clickOptions("+i+","+n+",'"+selects[i].name+"')"); }} function mouseSelects(name){ var sincn = 'select_info_' + name; $(sincn).onmouseover = function(){ if(this.className=='tag_select') this.className='tag_select_hover'; } $(sincn).onmouseout = function(){ if(this.className=='tag_select_hover') this.className='tag_select'; } if (isIE){ $(sincn).onclick = new Function("clickSelects('"+name+"');window.event.cancelBubble = true;"); } else if(!isIE){ $(sincn).onclick = new Function("clickSelects('"+name+"');"); $('select_info_' +name).addEventListener("click", stopBubbling, false); } } function clickSelects(name){ var sincn = 'select_info_' + name; var sinul = 'options_' + name; for (i=0;i<selects.length;i++){ if(selects[i].name == name){ if( $(sincn).className =='tag_select_hover'){ $(sincn).className ='tag_select_open'; $(sinul).style.display = ''; } else if( $(sincn).className =='tag_select_open'){ $(sincn).className = 'tag_select_hover'; $(sinul).style.display = 'none'; } } else{ $('select_info_' + selects[i].name).className = 'tag_select'; $('options_' + selects[i].name).style.display = 'none'; } } } function clickOptions(i, n, name){ var li = $('options_' + name).getElementsByTagName('li'); $('selected_' + name).className='open'; $('selected_' + name).id=''; li[n].id='selected_' + name; li[n].className='open_hover'; $('select_' + name).removeChild($('select_info_' + name)); select_info = document.createElement('div'); select_info.id = 'select_info_' + name; select_info.className='tag_select'; select_info.style.cursor='pointer'; $('options_' + name).parentNode.insertBefore(select_info,$('options_' + name)); mouseSelects(name); $('select_info_' + name).appendChild(document.createTextNode(li[n].innerHTML)); $( 'options_' + name ).style.display = 'none' ; $( 'select_info_' + name ).className = 'tag_select'; selects[i].options[n].selected = 'selected'; } window.onload = function(e) { bodyclick = document.getElementsByTagName('body').item(0); rSelects(); bodyclick.onclick = function(){ for (i=0;i<selects.length;i++){ $('select_info_' + selects[i].name).className = 'tag_select'; $('options_' + selects[i].name).style.display = 'none'; } }}</script></head><body><div id="macstyle1"> <select > <option value="GMT-12:00">GMT-12:00 日界線西</option> <option value="GMT-11:00">GMT-11:00 中途島，薩摩亞群島</option> <option value="GMT-10:00">GMT-10:00 夏威夷</option> <option value="GMT-9:00">GMT-9:00 阿拉斯加</option> <option value="GMT-8:00">GMT-8:00 太平洋時間(美國和加拿大)</option> <option value="GMT-7:00">GMT-7:00 山地時間(美國和加拿大)</option> <option value="GMT-6:00">GMT-6:00 中部時間(美國和加拿大)</option> <option value="GMT-5:00">GMT-5:00 東部時間(美國和加拿大)</option> <option value="GMT-4:30">GMT-4:30 加拉斯加</option> <option value="GMT-4:00">GMT-4:00 大西洋時間(加拿大)</option> <option value="GMT-3:30">GMT-3:30 紐芬蘭</option> <option value="GMT-3:00">GMT-3:00 喬治郭、巴西利亞</option> <option value="GMT-2:00">GMT-2:00 中大西洋</option> <option value="GMT-1:00">GMT-1:00 佛得角群島、亞速爾群島</option> <option value="GMT-0:00">GMT-0:00 都柏林、愛丁堡、倫敦</option> <option value="GMT+1:00">GMT+1:00 阿姆斯特丹、柏林、羅馬、巴黎</option> <option value="GMT+2:00">GMT+2:00 雅典、耶路撒冷、伊斯坦布爾</option> <option value="GMT+3:00">GMT+3:00 巴格達、科威特、莫斯科</option> <option value="GMT+3:30">GMT+3:30 德黑蘭</option> <option value="GMT+4:00">GMT+4:00 高加索標準時間</option> <option value="GMT+4:30">GMT+4:30 喀布爾</option> <option value="GMT+5:00">GMT+5:00 伊斯蘭堡、卡拉奇、塔什干</option> <option value="GMT+5:30">GMT+5:30 馬德拉斯、孟買、新德里</option> <option value="GMT+5:45">GMT+5:45 加德滿都</option> <option value="GMT+6:00">GMT+6:00 阿拉木圖、新西伯利亞、達卡</option> <option value="GMT+6:30">GMT+6:30 仰光</option> <option value="GMT+7:00">GMT+7:00 曼谷、河內(nèi)、雅加達</option> <option value="GMT+8:00" selected="selected">GMT+8:00 北京、烏魯木齊、新加坡</option> <option value="GMT+9:00">GMT+9:00 漢城、東京、大阪、札幌</option> <option value="GMT+9:30" >GMT+9:30 阿德萊德、達爾文</option> <option value="GMT+10:00" >GMT+10:00 墨爾本、悉尼、堪培拉</option> <option value="GMT+11:00">GMT+11:00 馬加丹、索羅門群島</option> <option value="GMT+12:00">GMT+12:00 奧克蘭、惠靈頓</option> <option value="GMT+13:00">GMT+13:00 努庫阿洛法</option> </select></div> </body></html>
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