Android studio 编译出现的问题记录

1、app:transformClassesWithJarMergingForDebug'.

Error:Execution failed for task ':app:transformClassesWithJarMergingForDebug'. > com.android.build.transform.api.TransformException: java.util.zip.ZipException: duplicate entry: > android/support/v7/cardview/BuildConfig.class

解决办法：

1、在 Terminal 输入：./gradlew clean

2、在菜单中选择: Build -> Clean Project

2、Error:Unable to resolve dependency for ':app@releaseUnitTest/compileClasspath': Could not download junit.jar (junit:junit:4.12)

<a href="openFile:/Users/shenjiaqi/Documents/sjq/annotation/app/build.gradle">Open File</a><br><a href="Unable to resolve dependency for &#39;:app@releaseUnitTest/compileClasspath&#39;: Could not download junit.jar (junit:junit:4.12)">Show Details</a>

解决办法：确保在 app 的 build.gradle 中包含下面语句：

repositories {
    google()
    jcenter()
    maven {url 'https://jitpark.io/'}
}

完整版如下：

apply plugin: 'com.android.application'

android {
    compileSdkVersion 27
    buildToolsVersion '26.0.2'
    defaultConfig {
        applicationId "com.sjq.recycletest"
        minSdkVersion 15
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }

    repositories {
        google()
        jcenter()
    }

    sourceSets {
        main {
            manifest.srcFile 'src/main/AndroidManifest.xml'
            java.srcDirs = ['src/main/java', 'src/main/aidl']
            resources.srcDirs = ['src/main/java', 'src/main/aidl']
            aidl.srcDirs = ['src/main/aidl']
            res.srcDirs = ['src/main/res']
            assets.srcDirs = ['src/main/assets']
        }
    }
}

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    implementation 'com.android.support:appcompat-v7:27.1.1'
    implementation 'com.android.support:recyclerview-v7:27.1.1'
    testImplementation 'junit:junit:4.12'
}

3、注解报错Annotation processors must be explicitly declared now.

解决办法：

在app的build中

android {
    ...
    defaultConfig {
        ...
        //添加如下配置就OK了
        javaCompileOptions { annotationProcessorOptions { includeCompileClasspath = true } }
    }
    ...
}