Maui blazor ios 按设备类型设置是否启用safeArea

Densen20142024-02-10 15:57

需求，新做了个app，使用的是maui blazor技术，里面用了渐变背景，在默认启用SafeArea情况下，底部背景很突兀

由于现版本maui在SafeArea有点bug，官方教程的<ContentPage SafeArea=false不生效，于是要用以下代码hack一下

         Microsoft.Maui.Handlers.LayoutHandler.Mapper.AppendToMapping("Custom", (h, v) =>
         {
             if (v is Layout layout)
             {
                 layout.IgnoreSafeArea = true;
             }
         });

带来的问题是，网页上下穿透了。

继续深入研究，用以下代码设置刘海屏上边距

 protected override void OnAppearing()
 {
     base.OnAppearing();
     if (withSafeArea)
     {
         var safeInsets = On<iOS>().SafeAreaInsets();
             On<iOS>().SetUseSafeArea(false);
             safeInsets.Top = 35;
             Padding = safeInsets;
     } 
 }

存在的问题是，非刘海屏设备也设置了上边距

最终代码，检查设备类型，按需配置上边距

using Microsoft.Maui.Controls.PlatformConfiguration;
using Microsoft.Maui.Controls.PlatformConfiguration.iOSSpecific;

namespace MyApp.Maui;

public partial class MainPage : ContentPage
{
bool withSafeArea = false;
public MainPage()
{
InitializeComponent();

     if (DeviceInfo.Current.Idiom == DeviceIdiom.Phone)
     {
         var screenSize = DeviceDisplay.MainDisplayInfo;
         if (screenSize.Height / screenSize.Density >= 812.0f)
         {
             withSafeArea = true;
         }
     }

     if (withSafeArea) { 
         Microsoft.Maui.Handlers.LayoutHandler.Mapper.AppendToMapping("Custom", (h, v) =>
         {
             if (v is Layout layout)
             {
                 layout.IgnoreSafeArea = true;
             }
         });
     }
 }

 protected override void OnAppearing()
 {
     base.OnAppearing();
     if (withSafeArea)
     {
         var safeInsets = On<iOS>().SafeAreaInsets();
             On<iOS>().SetUseSafeArea(false);
             safeInsets.Top = 35;
             Padding = safeInsets;
     } 
 }

}

题外话，网页可加上 viewport-fit=cover 效果更好
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no, viewport-fit=cover" />