AppCompat ActionBar加载失败，出现未知错误

Question

Failed to load AppCompatActionBar with unknown error.

dependencies {
    classpath 'com.android.tools.build:gradle:3.1.3'
}

Build.gradle(Module:app)

dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'com.android.support:appcompat-v7:28.0.0-beta01'
implementation 'com.android.support.constraint:constraint-layout:1.1.2'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.1'
androidTestImplementation 'com.android.support.test.espresso:espresso- 
core:3.0.2'
}

Answer 1

Try This

    implementation 'com.android.support:appcompat-v7:26.0.0'

with:

    buildToolsVersion '26.0.0' 

and

    classpath 'com.android.tools.build:gradle:3.1.3'