Android Studio 3.1 does not render xml file due to a java class missing

Question

It always shows me this error in the massages:

java.lang.ClassNotFoundException: android.view.View$OnUnhandledKeyEventListener

My project is literally Hello, World! and I just open Android Studio and click on the empty activity and then wait for the build to finish, but it doesn't render the app.

I reinstalled Android Studio and JDK 10. But it doesn't work. The project shows fine in virtual device and I can even edit Hello, World! to any string, but in the XML view, it just shows a white screen:

.

Here is the stack trace:

java.lang.ClassNotFoundException: android.view.View$OnUnhandledKeyEventListener
    at org.jetbrains.android.uipreview.ModuleClassLoader.load(ModuleClassLoader.java:180)
    at com.android.tools.idea.rendering.RenderClassLoader.findClass(RenderClassLoader.java:61)
    at org.jetbrains.android.uipreview.ModuleClassLoader.findClass(ModuleClassLoader.java:118)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    at org.jetbrains.android.uipreview.ModuleClassLoader.loadClass(ModuleClassLoader.java:213)
    at android.support.v7.widget.ActionBarContainer.<init>(ActionBarContainer.java:62)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at org.jetbrains.android.uipreview.ViewLoader.createNewInstance(ViewLoader.java:481)
    at org.jetbrains.android.uipreview.ViewLoader.loadClass(ViewLoader.java:264)
    at org.jetbrains.android.uipreview.ViewLoader.loadView(ViewLoader.java:222)
    at com.android.tools.idea.rendering.LayoutlibCallbackImpl.loadView(LayoutlibCallbackImpl.java:209)
    at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:337)
    at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:348)
    at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:248)
    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:730)
    at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:863)
    at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:72)
    at android.view.LayoutInflater.rInflate(LayoutInflater.java:837)
    at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:824)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:423)
    at com.android.layoutlib.bridge.bars.BridgeActionBar.<init>(BridgeActionBar.java:89)
    at com.android.layoutlib.bridge.bars.AppCompatActionBar.<init>(AppCompatActionBar.java:68)
    at com.android.layoutlib.bridge.impl.Layout.createActionBar(Layout.java:277)
    at com.android.layoutlib.bridge.impl.Layout.<init>(Layout.java:161)
    at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:288)
    at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:384)
    at com.android.tools.idea.layoutlib.LayoutLibrary.createSession(LayoutLibrary.java:193)
    at com.android.tools.idea.rendering.RenderTask.createRenderSession(RenderTask.java:544)
    at com.android.tools.idea.rendering.RenderTask.lambda$inflate$3(RenderTask.java:678)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Answer 1

Yes, it happens. You can fix it easily.

The first method:

Open build.gradle (Module: app) under Gradle Scripts and change version alpha3 to alpha1 and Sync now

implementation 'com.android.support:appcompat-v7:28.0.0-alpha1'

The second method:

Open file style.xml under res → values → style.xml and change this line:

style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">

Put Base. before Theme.AppCompat.Light.DarkActionBar like

style name="AppTheme" parent="Base.Theme.AppCompat.Light.DarkActionBar">

Answer 2

- Use Alpha/Beta at your own risk

• You are developing an app, so you don't want to face these types of issues. So I suggest you always use the stable version of every dependency.

The issue you faced was due to using an alpha version of the AppCompat library. Use the stable version to get rid of this issue now and in the future.

1. Use the android.support stable version

Currently 27.1.1 is the latest version of AppComactV7. You can see the Maven Repo link to find out the latest.

final def SUPPORT_VERSION = "27.1.1"
implementation "com.android.support:appcompat-v7:$SUPPORT_VERSION"
implementation "com.android.support:design:$SUPPORT_VERSION" // use only if already using

I use definitions to have the same version for all support versions. Also ignore the design library if you are not already using it.

2. Downgrade compileSdkVersion and targetSdkVersion (optional)

You also need to downgrade your compileSdkVersion and targetSdkVersion to remove some Gradle warnings.

So use the below versions.

compileSdkVersion 27
targetSdkVersion 27

Read about Alpha and Beta releases.

Answer 3

Go to
Gradle scripts>build.gradle(module app) > change 'com.android.support:appcompat-v7:28.0.0-alpha3' to 'com.android.support:appcompat-v7:28.0.0-alpha1'

You may have something other than alpha3 after "-v7:28.0.0-" whatever it is just change it to alpha1.