关于在gralde 3.6.0以上跑示例同时使用了androidx的同学看这里，有2个坑：

• 1、crash错误：Caused by: java.lang.ClassNotFoundException: Didn't find class "androidx.appcompat.R$drawable"
• 2、Logcat 看不到日志输出

为啥会有这2个问题？

• 第一个问题原因是：gradle 3.6.0以上R类不会转为.class文件而会转成jar，因此在Transform实现中需要单独拷贝，TransformInvocation.inputs.jarInputs
• 第二个问题是因为，androidx中，AppCompatActivity的报名变了，因此在ClassVisitor中，判断条件要更改

解决方案：

第一个问题的解决方案：在transform方法中，inputs.each block 中添加如下代码：

 transformInput.jarInputs.forEach {
            it.file.copyTo(
                info.outputProvider.getContentLocation(it.name, inputTypes, scopes, Format.JAR),
                overwrite = true
            )
        }

或者：

transformInput.jarInputs.each { JarInput jarInput ->
                File file = jarInput.file
                System.out.println("find jar input: " + file.name)
                def dest = outputProvider.getContentLocation(jarInput.name,
                        jarInput.contentTypes,
                        jarInput.scopes, Format.JAR)
                FileUtils.copyFile(file, dest)
            }

第二个问题的解决方案就很简单：在ClassVisitor类的的viditmethod方法中，将下面的代码：

 if(superClassname.equals("android/support/v7/AppCompatActivity")){
            if(name.startsWith("onCreate")){
               return new LifeCycleMethodVisitor(methodVisitor,className,name);
            }
        }

改为

 if(superClassname.equals("androidx/appcompat/app/AppCompatActivity")){
            if(name.startsWith("onCreate")){
               return new LifeCycleMethodVisitor(methodVisitor,className,name);
            }
        }

java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.asmlifecycledemo/com.example.asmlifecycledemo.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.example.asmlifecycledemo.MainActivity" on path: DexPathList[[zip file "/data/app/com.example.asmlifecycledemo-HlJlwafushUImzYDu1LOQg==/base.apk"],nativeLibraryDirectories=[/data/app/com.example.asmlifecycledemo-HlJlwafushUImzYDu1LOQg==/lib/arm64, /system/lib64, /vendor/lib64]]

    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2914)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3100)
    at android.app.ActivityThread.-wrap11(Unknown Source:0)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1804)
    at android.os.Handler.dispatchMessage(Handler.java:106)
    at android.os.Looper.loop(Looper.java:192)
    at android.app.ActivityThread.main(ActivityThread.java:6907)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:549)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:828)
 Caused by: java.lang.ClassNotFoundException: Didn't find class "com.example.asmlifecycledemo.MainActivity" on path: DexPathList[[zip file "/data/app/com.example.asmlifecycledemo-HlJlwafushUImzYDu1LOQg==/base.apk"],nativeLibraryDirectories=[/data/app/com.example.asmlifecycledemo-HlJlwafushUImzYDu1LOQg==/lib/arm64, /system/lib64, /vendor/lib64]]
    at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:125)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
    at android.app.Instrumentation.newActivity(Instrumentation.java:1180)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2904)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3100) 
    at android.app.ActivityThread.-wrap11(Unknown Source:0) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1804) 
    at android.os.Handler.dispatchMessage(Handler.java:106) 
    at android.os.Looper.loop(Looper.java:192) 
    at android.app.ActivityThread.main(ActivityThread.java:6907) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:549) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:828) 

可以在编译后生成的文件中，看到预期的代码。

一下是崩溃日志，一启动就会崩溃。但是如果和课程中一样只是加入Log的方法没有这个问题。
2020-09-10 15:39:47.556 16981-16981/? E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.wondroid.transforminject, PID: 16981
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.wondroid.transforminject/com.wondroid.transforminject.MainActivity}: java.lang.ClassNotFoundException: Didn't find class "com.wondroid.transforminject.MainActivity" on path: DexPathList[[zip file "/data/app/com.wondroid.transforminject-o5Gj4PwPLYWk0oRKUyulcg==/base.apk"],nativeLibraryDirectories=[/data/app/com.wondroid.transforminject-o5Gj4PwPLYWk0oRKUyulcg==/lib/arm64, /system/lib64, /system/product/lib64]]
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3228)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3443)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2040)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:224)
at android.app.ActivityThread.main(ActivityThread.java:7520)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:539)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)
Caused by: java.lang.ClassNotFoundException: Didn't find class "com.wondroid.transforminject.MainActivity" on path: DexPathList[[zip file "/data/app/com.wondroid.transforminject-o5Gj4PwPLYWk0oRKUyulcg==/base.apk"],nativeLibraryDirectories=[/data/app/com.wondroid.transforminject-o5Gj4PwPLYWk0oRKUyulcg==/lib/arm64, /system/lib64, /system/product/lib64]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:230)
at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
at android.app.AppComponentFactory.instantiateActivity(AppComponentFactory.java:95)
at androidx.core.app.CoreComponentFactory.instantiateActivity(CoreComponentFactory.java:41)
at android.app.Instrumentation.newActivity(Instrumentation.java:1251)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3216)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3443) 
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83) 
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2040) 
at android.os.Handler.dispatchMessage(Handler.java:107) 
at android.os.Looper.loop(Looper.java:224) 
at android.app.ActivityThread.main(ActivityThread.java:7520) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:539) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950) 

2020-04-12 22:03:24.204 18100-18100/com.laojizhang.compile_insert E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.laojizhang.compile_insert, PID: 18100
java.lang.NoClassDefFoundError: Failed resolution of: Landroidx/appcompat/R$drawable;
at androidx.appcompat.widget.AppCompatDrawableManager$1.(AppCompatDrawableManager.java:63)
at androidx.appcompat.widget.AppCompatDrawableManager.preload(AppCompatDrawableManager.java:57)
at androidx.appcompat.app.AppCompatDelegateImpl.(AppCompatDelegateImpl.java:328)
at androidx.appcompat.app.AppCompatDelegateImpl.(AppCompatDelegateImpl.java:278)
at androidx.appcompat.app.AppCompatDelegate.create(AppCompatDelegate.java:221)
at androidx.appcompat.app.AppCompatActivity.getDelegate(AppCompatActivity.java:543)
at androidx.appcompat.app.AppCompatActivity.attachBaseContext(AppCompatActivity.java:98)
at android.app.Activity.attach(Activity.java:6909)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2750)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
at android.app.ActivityThread.-wrap11(Unknown Source:0)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
at android.os.Handler.dispatchMessage(Handler.java:105)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6541)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
Caused by: java.lang.ClassNotFoundException: Didn't find class "androidx.appcompat.R$drawable" on path: DexPathList[[zip file "/data/app/com.laojizhang.compile_insert-6QI6CYdHxt2f3XyKbd9MaQ==/base.apk"],nativeLibraryDirectories=[/data/app/com.laojizhang.compile_insert-6QI6CYdHxt2f3XyKbd9MaQ==/lib/x86, /system/lib, /vendor/lib]]
at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:93)
at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
at androidx.appcompat.widget.AppCompatDrawableManager$1.(AppCompatDrawableManager.java:63) 
at androidx.appcompat.widget.AppCompatDrawableManager.preload(AppCompatDrawableManager.java:57) 
at androidx.appcompat.app.AppCompatDelegateImpl.(AppCompatDelegateImpl.java:328) 
at androidx.appcompat.app.AppCompatDelegateImpl.(AppCompatDelegateImpl.java:278) 
at androidx.appcompat.app.AppCompatDelegate.create(AppCompatDelegate.java:221) 
at androidx.appcompat.app.AppCompatActivity.getDelegate(AppCompatActivity.java:543) 
at androidx.appcompat.app.AppCompatActivity.attachBaseContext(AppCompatActivity.java:98) 
at android.app.Activity.attach(Activity.java:6909) 
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2750) 
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892) 
at android.app.ActivityThread.-wrap11(Unknown Source:0) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593) 
at android.os.Handler.dispatchMessage(Handler.java:105) 
at android.os.Looper.loop(Looper.java:164) 
at android.app.ActivityThread.main(ActivityThread.java:6541) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767) 

java.lang.ClassNotFoundException: Didn't find class "android.support.constraint.ConstraintLayout" on path: DexPathList[[zip file "/data/app/com.example.asmlifecycledemo-2/base.apk"],nativeLibraryDirectories=[/data/app/com.example.asmlifecycledemo-2/lib/x86, /system/lib, /vendor/lib]]

已经申请了读写SD权限
Suppressed: java.io.IOException: No original dex files found for dex location /storage/emulated/0/say_something_hotfix.jar

一步一坑走过来 最后死在的classNotFound， 下面是报错
2020-05-26 15:50:54.649 12581-12581/com.android.internal.policy W/System.err: java.lang.ClassNotFoundException: Didn't find class "com.android.internal.policy.ClassLoader.android.SayHotFix" on path: DexPathList[[zip file "/storage/emulated/0/say_something_hotfix.jar"],nativeLibraryDirectories=[/system/lib, /system/product/lib]]
2020-05-26 15:50:54.649 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:196)
2020-05-26 15:50:54.649 12581-12581/com.android.internal.policy W/System.err: at java.lang.ClassLoader.loadClass(ClassLoader.java:379)
2020-05-26 15:50:54.649 12581-12581/com.android.internal.policy W/System.err: at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
2020-05-26 15:50:54.649 12581-12581/com.android.internal.policy W/System.err: at com.android.internal.policy.mainActivity$1.onClick(mainActivity.java:46)
2020-05-26 15:50:54.649 12581-12581/com.android.internal.policy W/System.err: at android.view.View.performClick(View.java:7125)
2020-05-26 15:50:54.650 12581-12581/com.android.internal.policy W/System.err: at android.view.View.performClickInternal(View.java:7102)
2020-05-26 15:50:54.650 12581-12581/com.android.internal.policy W/System.err: at android.view.View.access$3500(View.java:801)
2020-05-26 15:50:54.651 12581-12581/com.android.internal.policy W/System.err: at android.view.View$PerformClick.run(View.java:27336)
2020-05-26 15:50:54.651 12581-12581/com.android.internal.policy W/System.err: at android.os.Handler.handleCallback(Handler.java:883)
2020-05-26 15:50:54.651 12581-12581/com.android.internal.policy W/System.err: at android.os.Handler.dispatchMessage(Handler.java:100)
2020-05-26 15:50:54.651 12581-12581/com.android.internal.policy W/System.err: at android.os.Looper.loop(Looper.java:214)
2020-05-26 15:50:54.652 12581-12581/com.android.internal.policy W/System.err: at android.app.ActivityThread.main(ActivityThread.java:7356)
2020-05-26 15:50:54.652 12581-12581/com.android.internal.policy W/System.err: at java.lang.reflect.Method.invoke(Native Method)
2020-05-26 15:50:54.652 12581-12581/com.android.internal.policy W/System.err: at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
2020-05-26 15:50:54.652 12581-12581/com.android.internal.policy W/System.err: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: Suppressed: java.io.IOException: No original dex files found for dex location /storage/emulated/0/say_something_hotfix.jar
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.DexFile.openDexFileNative(Native Method)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.DexFile.openDexFile(DexFile.java:365)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.DexFile.(DexFile.java:107)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.DexFile.(DexFile.java:80)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.DexPathList.loadDexFile(DexPathList.java:444)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.DexPathList.makeDexElements(DexPathList.java:403)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.DexPathList.(DexPathList.java:164)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.BaseDexClassLoader.(BaseDexClassLoader.java:126)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.BaseDexClassLoader.(BaseDexClassLoader.java:84)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at dalvik.system.DexClassLoader.(DexClassLoader.java:55)
2020-05-26 15:50:54.653 12581-12581/com.android.internal.policy W/System.err: at com.android.internal.policy.mainActivity$1.onClick(mainActivity.java:42)
2020-05-26 15:50:54.654 12581-12581/com.android.internal.policy W/System.err: ... 11 more