问题描述
我想使用 Xamarin.forms 在 Android 上的整个应用程序中保持沉浸式模式。我读过一些博客和帖子。 This one 有效,但仅在我按下输入文本框或滚动屏幕之前。我想避免这种情况。 This question 争论我的担忧,但我不明白解决方案。也许它已经过时了。我的安卓设备是 7.1,这是我在 .Android
MainActivity
,void OnCreate
,void OnCreate
上的代码:
public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity{
protected override void OnCreate(Bundle savedInstanceState){
Xamarin.Essentials.Platform.Init(this,savedInstanceState);
global::Xamarin.Forms.Forms.Init(this,savedInstanceState);
TabLayoutResource = Resource.Layout.Tabbar;
ToolbarResource = Resource.Layout.Toolbar;
base.OnCreate(savedInstanceState);
LoadApplication(new App());
ImmersiveMode();
}
public override void OnRequestPermissionsResult(int requestCode,string[] permissions,[GeneratedEnum] Android.Content.PM.Permission[] grantResults){
Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode,permissions,grantResults);
base.OnRequestPermissionsResult(requestCode,grantResults);
}
public void ImmersiveMode() {
int uiOptions = (int)(Forms.Context as Activity).Window.DecorView.systemUIVisibility;
uiOptions |= (int)systemUIFlags.Fullscreen;
uiOptions |= (int)systemUIFlags.HideNavigation;
uiOptions |= (int)systemUIFlags.ImmersiveSticky;
(Forms.Context as Activity).Window.DecorView.systemUIVisibility = (StatusBarVisibility)uiOptions;
}
}
我该如何解决这个问题?您能否具体说明我应该在哪里找到新代码。我是 Xamarin.Forms 的菜鸟,对我来说看起来很棘手。谢谢
编辑:这段代码:
this.Window.AddFlags(WindowManagerFlags.Fullscreen);
在 .Android
MainActivity
上隐藏带有 wifi 信号、时间、蓝牙等的 Android 栏
有没有像这样的一行来隐藏这个 android 按钮?
解决方法
Window.DecorView.SystemUiVisibility
自 Android R (11)
起已弃用。在这个 API 版本中有一种新方法可以做到这一点。
以下是我在我的一个应用中使用的代码。我不得不重写 MainActivity 类中的一堆方法。
using System;
using Android.App;
using Android.Content.PM;
using Android.Runtime;
using Android.OS;
using Android.Views;
namespace SampleApp.Droid
{
[Activity(Label = "SampleApp",Icon = "@mipmap/icon",Theme = "@style/MainTheme",MainLauncher = true,ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation | ConfigChanges.UiMode | ConfigChanges.ScreenLayout | ConfigChanges.SmallestScreenSize )]
public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity
{
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
Xamarin.Essentials.Platform.Init(this,savedInstanceState);
global::Xamarin.Forms.Forms.Init(this,savedInstanceState);
LoadApplication(new App());
SetFullscreenFlags();
}
protected override void OnResume()
{
base.OnResume();
SetFullscreenFlags();
}
public override void OnWindowFocusChanged(bool hasFocus)
{
base.OnWindowFocusChanged(hasFocus);
SetFullscreenFlags();
}
protected void SetFullscreenFlags()
{
var attrs = Window.Attributes;
attrs.Flags |= WindowManagerFlags.Fullscreen;
Window.Attributes = attrs;
// BuildVersionCodes has a wrong value for Android R (1000 instead of 30)
// https://github.com/xamarin/xamarin-android/issues/5723
// if (Build.VERSION.SdkInt >= BuildVersionCodes.R)
if ((int)Build.VERSION.SdkInt >= 30)
{
Window.SetDecorFitsSystemWindows(false);
if (Window.InsetsController != null)
{
Window.InsetsController.Hide(WindowInsets.Type.NavigationBars());
Window.InsetsController.Hide(WindowInsets.Type.StatusBars());
Window.InsetsController.Hide(WindowInsets.Type.SystemBars());
Window.InsetsController.Show(WindowInsets.Type.Ime());
}
}
else
{
var uiOptions = (int)Window.DecorView.SystemUiVisibility;
var newUiOptions = (int)uiOptions;
newUiOptions |=
(int)SystemUiFlags.LayoutStable |
(int)SystemUiFlags.LayoutHideNavigation |
(int)SystemUiFlags.LayoutFullscreen |
(int)SystemUiFlags.HideNavigation |
(int)SystemUiFlags.Fullscreen |
(int)SystemUiFlags.ImmersiveSticky;
Window.DecorView.SystemUiVisibility = (StatusBarVisibility)newUiOptions;
}
}
public override void OnRequestPermissionsResult(int requestCode,string[] permissions,[GeneratedEnum] Android.Content.PM.Permission[] grantResults)
{
Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode,permissions,grantResults);
base.OnRequestPermissionsResult(requestCode,grantResults);
}
}
}
之前,我还实现了 View.IOnSystemUiVisibilityChangeListener
接口。但它也已弃用,并将在未来版本中删除:
public class MainActivity : global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity,View.IOnSystemUiVisibilityChangeListener
{
protected override void OnCreate(Bundle savedInstanceState)
{
// omitted code
Window.DecorView.SetOnSystemUiVisibilityChangeListener(this);
}
public void OnSystemUiVisibilityChange([GeneratedEnum] StatusBarVisibility visibility)
{
SetFullscreenFlags();
}
}
编辑:
如果您想在用户将某些输入控件聚焦在屏幕上后保持沉浸模式,您可以实现 ViewTreeObserver.IOnGlobalFocusChangeListener
界面。我是这样做的:
public class MainActivity :
global::Xamarin.Forms.Platform.Android.FormsAppCompatActivity,ViewTreeObserver.IOnGlobalFocusChangeListener
{
protected override void OnCreate(Bundle savedInstanceState)
{
// ommited code
}
public override void SetContentView(View view)
{
base.SetContentView(view);
if (view?.ViewTreeObserver != null)
view.ViewTreeObserver.AddOnGlobalFocusChangeListener(this);
}
public override void SetContentView(View view,ViewGroup.LayoutParams @params)
{
base.SetContentView(view,@params);
if (view?.ViewTreeObserver != null)
view.ViewTreeObserver.AddOnGlobalFocusChangeListener(this);
}
public void OnGlobalFocusChanged(View oldFocus,View newFocus)
{
SetFullscreenFlags();
}
}