build.gradle

# Our merge report task

task jacocoTestReport(type: JacocoReport, dependsOn: ['testDebugUnitTest', 'createDebugCoverageReport']) {

    reports {
        xml.enabled = true
        html.enabled = true
    }

    def fileFilter = ['**/R.class', '**/R$*.class', '**/BuildConfig.*', '**/Manifest*.*', '**/*Test*.*', 'android/**/*.*']
    def debugTree = fileTree(dir: "$project.buildDir/intermediates/classes/debug", excludes: fileFilter)
    def mainSrc = "$project.projectDir/src/main/java"

    sourceDirectories = files([mainSrc])
    classDirectories = files([debugTree])
    executionData = fileTree(dir: project.buildDir, includes: [
            'jacoco/testDebugUnitTest.exec', 'outputs/code-coverage/connected/*coverage.ec'
    ])
}