Xamarin 常见问题解决方案汇总

出现如下提示，错误: 找不到或无法加载主类 com.sun.tools.javac.MainMSB6006:

或

閿欒: 绋嬪簭鍖卆ndroid.support.v4.view.ViewPager涓嶅瓨鍦?

删掉bin,obj文件夹重新生成

还是没有效果的话参照这里http://blog.csdn.net/cctvcqupt/article/details/46636809

Your emulator is out of date, please update by launching Android Studio:
- Start Android Studio
- Select menu "Tools > Android > SDK Manager"
- Click "SDK Tools" tab
- Check "Android SDK Tools" checkbox
- Click "OK"

这个问题的解决方案其实不需要我汇总。。。错误信息很明白了

打开 Visual Studio,工具>Android>SDK 管理器，更新 Android SDK Tools

开启 ProGuard 后无法编译

https://forums.xamarin.com/discussion/54656/proguard-with-api-23-wont-compile-on-release-with-google-play-services-27-0-0-0
https://forums.xamarin.com/discussion/45210/enable-proguard-error-c-program-files-access-is-denied
https://www.shisujie.com/blog/Enable-ProGuard-Cause-Java-Exit

运行时错误不显示错误详情

监听

AndroidEnvironment.UnhandledExceptionRaiser

事件

System.IO.IsolatedStorage 无法使用

Xamarin Android nuget上的 System.IO.IsolatedStorage 是假的，请换用 System.IO 读写

System.IO 操作无效

确保路径分隔符正确

HttpWebRequest 的 AllowReadStreamBuffering 无法设置为 true

mono 目前没有实现这个属性，无解

iOS 无法生成

确保项目里的所有PNG都是有效的，还不行试试关闭优化 png 的选项

android 模拟器测试卡在部署阶段

生成，取消生成，然后再试一次

iOS 的优化 PNG 选项无法开启

删掉 iOS 项目中的无效 PNG 文件

Cannot build iOS App (Can not resolve reference: C:/Windows/Microsoft.NET/Framework/v4.0.30319/语言代码/mscorlib.resources.dll)

https://bugzilla.xamarin.com/show_bug.cgi?id=56213#c12

Hi All,
I'm sorry you're facing this bug. There is a workaround for both the build and debug issues:
1- On Windows, open the Visual Studio 2017 installation folder. (Default: C:\Program Files (x86)\Microsoft Visual Studio\2017\<Edition>\)
2- Navigate to MSBuild\Xamarin.
3- Open the Xamarin.Apple.Sdk.targets file in an editor with Administrator privileges.
4- At the end of the file you'll find a PropertyGroup (line 100), between the PropertyGroup tags add the following line:
<FrameworkPathOverride>$(TargetFrameworkRootPath)$(TargetFrameworkIdentifier)\$(TargetFrameworkVersion)</FrameworkPathOverride>

In case you're still able to reproduce this bug after applying the workaround, please let us know and attach a Detailed build output and the Xamarin Logs (Help -> Xamarin -> Zip Logs...)

Thanks!

在位于100行的PropertyGroup元素中加入这一行<FrameworkPathOverride>$(TargetFrameworkRootPath)$(TargetFrameworkIdentifier)\$(TargetFrameworkVersion)</FrameworkPathOverride>

DisplayAlert或UIAlertView在iOS无法正常工作

换用iPhone SE模拟器

启动模拟器后没有启动调试

不关闭模拟器重新调试

Effect的Control为null

Xamarin的Control里面是不含子元素的View,所以Control为null时试试Container

Android 7.0上不显示 SearchBar

设置HeightRequest为48

Unhandled Exception: System.TypeLoadException: Could not resolve type with token

重新生成项目

MSB3644 Xamarin.iOS,Version=v1.0 binding Microsoft.Common.CurrentVersion.targets

参考https://bugzilla.xamarin.com/show_bug.cgi?id=56213#c24

无法“存档”APK

But I found another strange workaround:
If I compile and Archive, the Archive will fail. Then I Archive once more and it will also fail. But now it is possible to Distribute the last failed Archive!
I have so far not found any problem at all with the distributed apk file. It runs without any problem and Google Play accepts it.

参考 https://forums.xamarin.com/discussion/86557/xamarin-archive-manager-fails-with-the-specified-path-file-name-or-both-are-too-long

发布生成的 APK 莫名闪退

试试打开 Nuget 管理器，看是否提示需要重启，按提示操作

https://stackoverflow.com/questions/44122396/after-updating-xamarin-forms-nuget-package-the-task-could-not-be-loaded-fr

还有一些问题参见这里

https://releases.xamarin.com/common-issues-in-the-xamarin-15-2-2-release-being-tracked-by-the-xamarin-team/

提示没有调用 super.OnCreated

清理解决方案

调试卡在使用临时签名签名

取消并重新调试

Android新创建的模拟器启动后立刻闪退且ADB工具无法复制文件到模拟器中

更新各种android tools