Try creating gradle wrapper with travis
diff --git a/.travis.yml b/.travis.yml
index 4463448..39f1ba8 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -29,5 +29,6 @@
before_install:
- yes | sdkmanager "platforms;android-28"
+ - gradle -b wrapper.gradle wrapper
script: "./gradlew build --stacktrace"
diff --git a/wrapper.gradle b/wrapper.gradle
new file mode 100644
index 0000000..33df39c
--- /dev/null
+++ b/wrapper.gradle
@@ -0,0 +1,3 @@
+task wrapper(type: Wrappper) {
+ gradleVersion = '4.10.1'
+}
\ No newline at end of file