uniapp获取底部安全距离以及状态栏高度等

.u-fixed-b {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 24rpx;
  padding-bottom: calc(24rpx + constant(safe-area-inset-bottom));
  padding-bottom: calc(24rpx + env(safe-area-inset-bottom));
  z-index: 50;
}

<template>
	<view class="container">
		<!-- 自定义顶部导航 -->
		<uni-nav-bar left-icon="left" backgroundColor="#FFFFFF" title="顶部导航" @clickLeft="backPage"></uni-nav-bar>
		
		<!-- 页面内容 -->
		<view class="page-content">
			<!-- ---------- -->
		</view>
	</view>
</template>

.container {
	background-color: #ffffff;
	height: 100%;
	padding-top: var(--status-bar-height);
	display: flex;
	flex-direction: column;
	position: absolute;
	top: 0;
	bottom: 0;
	left: 0;
	right: 0;
}