C# 如何在半透明的导航栏中调整阴影?
为了使导航栏半透明,我使用了自定义渲染器:C# 如何在半透明的导航栏中调整阴影?,c#,xamarin,xamarin.forms,xamarin.android,C#,Xamarin,Xamarin.forms,Xamarin.android,为了使导航栏半透明,我使用了自定义渲染器: using Xamarin.Forms; using Xamarin.Forms.Platform.Android; using Xamarin.Forms.Platform.Android.AppCompat; using AView = Android.Views.View; using App1; using Android.Content; using TransparentNavBarXForms.Droid.Renderers; [ass
using Xamarin.Forms;
using Xamarin.Forms.Platform.Android;
using Xamarin.Forms.Platform.Android.AppCompat;
using AView = Android.Views.View;
using App1;
using Android.Content;
using TransparentNavBarXForms.Droid.Renderers;
[assembly: ExportRenderer(typeof(CustomNavigationPage), typeof(CustomNavigationPageRenderer))]
namespace TransparentNavBarXForms.Droid.Renderers
{
public class CustomNavigationPageRenderer : NavigationPageRenderer
{
public CustomNavigationPageRenderer(Context context) : base(context)
{
}
IPageController PageController => Element as IPageController;
CustomNavigationPage CustomNavigationPage => Element as CustomNavigationPage;
protected override void OnLayout(bool changed, int l, int t, int r, int b)
{
CustomNavigationPage.IgnoreLayoutChange = true;
base.OnLayout(changed, l, t, r, b);
CustomNavigationPage.IgnoreLayoutChange = false;
int containerHeight = b;
PageController.ContainerArea = new Rectangle(0, 0, Context.FromPixels(r - l), Context.FromPixels(containerHeight-t));
for (var i = 0; i < ChildCount; i++)
{
AView child = GetChildAt(i);
if (child is Android.Support.V7.Widget.Toolbar)
{
continue;
}
child.Layout(0, 0, r, b);
}
}
}
}
使用Xamarin.Forms;
使用Xamarin.Forms.Platform.Android;
使用Xamarin.Forms.Platform.Android.AppCompat;
使用AView=Android.Views.View;
使用App1;
使用Android.Content;
使用TransparentNavBarXForms.Droid.Renderers;
[程序集:ExportRenderer(typeof(CustomNavigationPage)、typeof(CustomNavigationPageRenderer))]
命名空间TransparentNavBarXForms.Droid.Renderers
{
公共类CustomNavigationPageRenderer:NavigationPageRenderer
{
公共CustomNavigationPageRenderer(上下文):基础(上下文)
{
}
IPageController PageController=>元素作为IPageController;
CustomNavigationPage CustomNavigationPage=>元素作为CustomNavigationPage;
受保护覆盖仅限无效布局(布尔值已更改、整数l、整数t、整数r、整数b)
{
CustomNavigationPage.IgnoreLayoutChange=true;
仅基础布局(已更改,l、t、r、b);
CustomNavigationPage.IgnoreLayoutChange=false;
int containerHeight=b;
PageController.ContainerArea=新矩形(0,0,Context.FromPixels(r-l),Context.FromPixels(containerHeight-t));
对于(变量i=0;i
为了添加阴影,我将属性:android:elevation=“4dp”添加到Toolbar.axml阴影不仅从导航栏底部添加,而且从内部的不同侧面添加,由于透明效果,这是可见的。如何仅从下方制作阴影?是否有可能以不同的方式实现它
首先,如果导航栏的背景色是透明的,则无法设置
android:elevation=“4dp”
下面是创建阴影的另一种方法。您可以使用BoxView
模拟阴影。在内容页面中添加BoxView
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:d="http://xamarin.com/schemas/2014/forms/design"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
Title="test"
x:Class="CustomNavigateBar.MainPage">
<StackLayout>
<!-- add showdow here -->
<BoxView VerticalOptions="StartAndExpand" HeightRequest="10"/>
<!-- Place new controls here -->
<Label Text="Welcome to Xamarin.Forms!"
HorizontalOptions="Center"
VerticalOptions="CenterAndExpand" />
</StackLayout>
</ContentPage>
在android中使用自定义渲染器
[assembly: ExportRenderer(typeof(BoxView), typeof(MyBoxViewRenderer))]
namespace CustomNavigateBar.Droid
{
public class MyBoxViewRenderer: BoxRenderer
{
public MyBoxViewRenderer(Context context) : base(context) { }
protected override void OnElementChanged(ElementChangedEventArgs<BoxView> e)
{
base.OnElementChanged(e);
ViewGroup.SetBackgroundResource(Resource.Drawable.boxview_shadow);
}
}
}
[程序集:ExportRenderer(typeof(BoxView)、typeof(MyBoxViewRenderer))]
命名空间CustomNavigateBar.Droid
{
公共类MyBoxViewRenderer:BoxRenderer
{
公共MyBoxViewRenderer(上下文):基本(上下文){}
受保护的覆盖无效OnElementChanged(ElementChangedEventArgs e)
{
基础。一个要素发生变化(e);
ViewGroup.SetBackgroundResource(Resource.Drawable.boxview\u shadow);
}
}
}
boxview_shadow.xml
<?xml version="1.0" encoding="utf-8" ?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<shape android:shape="rectangle">
<solid android:color="#CABBBBBB" />
</shape>
</item>
</layer-list>
这是跑步
很抱歉延迟,如果导航栏不透明,您的解决方案可以正常工作。如果使用解决方案,则导航栏将失去透明度的效果。