由于项目需要，需要设计一个可以多选的ComboBox，看了一下文档，发现QML自带的ComboBox确实无法多选。看了一下ComboBox的实现，发现弹出的下拉菜单是用Menu实现的，看来只能自己重写了，毕竟Menu本身就是无法多选的！代码不多，直接看实现吧！

import QtQuick 2.5
import QtQuick.Controls 1.4
import QtQuick.Controls.Styles 1.4Item{id:rootimplicitWidth: 150implicitHeight: 30property alias model: lv.modelproperty var indexs: []property var m_text: ""function removeValue(arr,val) {      //删除数组中指定的内容arr数组，val内容for (var i = 0; i < arr.length; i++) {if (arr[i] == val) {arr.splice(i, 1)return arr;}}}Button{id: btnanchors.fill: parentText{anchors.fill: parentanchors.margins: 5anchors.rightMargin: 30text: m_texthorizontalAlignment: Text.AlignHCenterverticalAlignment: Text.AlignVCenterfont.pointSize: 12clip: trueelide: Text.ElideMiddle}onClicked: {sv.visible = !sv.visible;}Image{anchors.right: parent.rightanchors.top: parent.topwidth: root.heightheight:root.heightsource:"换成自己下拉按钮图片"}}Component{id: m_delRectangle{id:rectcolor:"white"implicitWidth: 150implicitHeight: 30property bool isSelect: falseText{anchors.fill: parenthorizontalAlignment:Text.AlignHCenterverticalAlignment: Text.AlignVCenterfont.pointSize: 15text: label}MouseArea{anchors.fill: parenthoverEnabled: trueonEntered: {if(!isSelect){rect.color = "#CDDCFE";}}onExited: {if(!isSelect){rect.color = "white"}}onClicked: {rect.isSelect = !rect.isSelect;if(!rect.isSelect){         //取消某项rect.color = "white"//删除文本中指定的字符串var arr = m_text.split(",");arr = removeValue(arr,label)m_text = arr.join(",");//删除数组中记录指定的内容indexs = removeValue(indexs,index);}else{                       //选择某项rect.color = "#F9E977"if(m_text.length == 0){m_text += label;}else{m_text += "," + label;}indexs.push(index)}}}}}ScrollView{id:svanchors.top:btn.bottomanchors.left: parent.leftwidth: parent.widthheight: 300visible: falseListView{id: lvdelegate:m_delanchors.fill: parent}}
}

有个地方和官方的ComboBox有些区别，就是需要点击按钮才会将下拉列表收起来，不知道怎样才能实现点击其他位置，关闭下拉列表，有知道的朋友告诉我一声，谢啦！