fix gradle property

Author: MasayukiSuda

gpuv/build.gradle

@@ -1,15 +1,13 @@
 apply plugin: 'com.android.library'
 
 android {
-    compileSdkVersion 28
-
-
+    compileSdkVersion COMPILE_SDK_VERSION as int
 
     defaultConfig {
-        minSdkVersion 21
-        targetSdkVersion 28
-        versionCode 1
-        versionName "1.0"
+        minSdkVersion COMPILE_MIN_SDK_VERSION as int
+        targetSdkVersion COMPILE_SDK_VERSION as int
+        versionCode VERSION_CODE as int
+        versionName VERSION_NAME
 
     }
 

gradle.properties

@@ -15,3 +15,8 @@ org.gradle.jvmargs=-Xmx1536m
 kotlin.code.style=official
 android.useAndroidX=true
 android.enableJetifier=true
+VERSION_NAME=0.1.0
+VERSION_CODE=1
+BUILD_TOOLS_VERSION=28.0.3
+COMPILE_SDK_VERSION=28
+COMPILE_MIN_SDK_VERSION=21

sample/build.gradle

@@ -3,11 +3,11 @@ apply plugin: 'kotlin-android'
 apply plugin: 'kotlin-android-extensions'
 
 android {
-    compileSdkVersion 28
+    compileSdkVersion COMPILE_SDK_VERSION as int
     defaultConfig {
         applicationId "com.daasuu.gpuvideoandroid"
-        minSdkVersion 21
-        targetSdkVersion 28
+        minSdkVersion COMPILE_MIN_SDK_VERSION as int
+        targetSdkVersion COMPILE_SDK_VERSION as int
         versionCode 1
         versionName "1.0"
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"