问题
I just updated my Android Studio to latest 3.0 and then the Layout Preview is not working anymore. I have tried open up different projects and they all have the same render issues. As I checked, I don't see any compile errors or gradle issues. So far, I tried
- Build Project
- Refresh Layout
- Clean Project
- Invalid Caches / Restart
The following attached screenshot shows that some classes cannot be initiated but I dont get why and how to fix them. Thank you very much. Any hints could help.
Updates: It seems there is a duplicate case at Render error in Android Studio 3.0 Layout Editor but mine problem is slightly different. The solution for above linked issue is to modify the theme to a more specific one by clarifying parent theme under Base.Theme.AppCompat.Light.DarkActionBar. However, I don't even have an ActionBar so I am looking for a solution for Theme.AppCompat.NoActionBar.
Before updating to 3.0, everything is fine. I wonder if I need to change deployment SDK/Version.
回答1:
OK, I tried to explore every possible solution but no work. I finally figured it out by changing the deployment SDK/Version. I changed all to 26 and it fixed my problems. As I tested version lower and higher, it seems only ver 26 can work.
android {
compileSdkVersion 26
buildToolsVersion '26.0.2'
...
defaultConfig {
targetSdkVersion 26
...
}
}
...
dependencies {
compile 'com.android.support:appcompat-v7:26.0.0'
compile 'com.android.support:design:26.0.0'
compile 'com.android.support:support-v13:26.0.0'
compile 'com.android.support:support-v4:26.0.0'
compile 'com.android.support:palette-v7:26.0.0'
...
}
So if the solution at Render error in Android Studio 3.0 Layout Editor does not work for you. You can try 26. Let me know.
回答2:
This is a serious bug in Android Studio 3.0, when using support libraries that are not version 26. As of November 2017, it's not yet fixed and it has been reported several times:
In Stackoverflow:
- Why preview not showing for many layout since update to android studio 3.0?
- Render error in Android Studio 3.0 Layout Editor
- Failed to load AppCompat ActionBar with unknown error in android studio
In Google Issue tracker:
- https://issuetracker.google.com/issues/68353097 - Cannot display preview of layout after update to Android Studio 3.0
- https://issuetracker.google.com/issues/68498497 - Android Studio 3.0 Preview ScrollView
- https://issuetracker.google.com/issues/68423477 - Rendering issue with layout preview after updating to Android Studio 3.0
- https://issuetracker.google.com/issues/68288395 - After upgrade android studio as 3.0, layout preview is not showing with error
- https://issuetracker.google.com/issues/65858429 - Preview is not working in Android Studio 3.0-Beta6
- https://issuetracker.google.com/issues/64028640 - Rendering problem still exists on AS 3.0 canary 8 "Failed to load AppCompat ActionBar with unknown error." and Failed to instantiate one of more classes on android.support:appcompat-v7:26.0.0-beta2
- https://issuetracker.google.com/issues/63786429 - Layout Editor Not Displaying Preview in Android Studio 3.0 Preview 7
Update April 2018: The minimum support library version is 25.4.0, for Android Studio 3.0 and 3.1. More info in the Google Issue Tracker links.
回答3:
JUST CHANGE alpha3 to alpha1 in gradle module app implementation 'com.android.support:appcompat-v7:28.0.0-alpha1'
回答4:
Click on Design tab >> Top corner layout option (Design, Blueprint) >> Select Force Refresh Layout.
回答5:
You need to install SDK platforms depends on which compat library you are using.
For example:
If you are using compile 'com.android.support:appcompat-v7:25.0.0'. Make sure SDk platforms API 25 is downloaded.
To check downloaded SDK platforms, goto
Tools-> Sdk Manager ->Sdk Platforms.
then download the required platforms depends on the library you are using.
Restart the Android studio to effect the changes.
回答6:
I had that same problem. After searching, I found that there was a problem with API 28, which was the one I had at that time. What I did was download the 26 and I could fix it. Go to Tools / SDK Manager / SDK Platforms / Download API 26 and delete another one we have.
来源：https://stackoverflow.com/questions/46996939/android-studio-3-0-layout-preview-render-issues