小程序设置 "navigationStyle": "custom"后在哪里自行定义导航栏样式?
https://segmentfault.com/q/1010000015377537
在 app.json 里进行更改 "navigationStyle":"custom" 即可全屏显示,然后自定义顶部样式
{
"pages":[
"pages/index/index",
"pages/logs/logs"
],
"window":{
"backgroundTextStyle":"light",
"navigationBarBackgroundColor": "#44c9fb",
"navigationBarTitleText": "小程序名字",
"navigationBarTextStyle":"#fff",
"navigationStyle":"custom"
}
}

封装成组件可参考这篇文章
微信小程序 自定义头部导航栏 navigationStyle
https://www.jianshu.com/p/7393c800ba09
