将以下代码放入要监听返回按钮的页面
//两秒内连续按两次返回键，退出
function exitApp(){
var n = 0;
var time1, time2;
api.addEventListener({
name: 'keyback'
}, function(ret, err){
if (n == 0) {
time1 = new Date().getTime();
n = 1;
api.toast({msg:'再按一次返回键退出'});
}else if(n==1){
time2 = new Date().getTime();
if (time2 - time1 < 2000) {
api.closeWidget({
id: api.appId, //填写自己的id
retData: {name:'closeWidget'},
silent:true
});
}else{
n=1;
time1=time2;
api.toast({msg:'再按一次返回键退出'});
}
}
});
}并在apiready代码中调用该函数，如下
apiready = function(){
exitApp();
}