BuildConfig not getting created correctly (Gradle Android)

I am trying to convert our Android application to a gradle build. I have the project and it's libraries building successfully. I am now trying to create separate apks for our various environments (dev/test/prod have different urls for the restful services they consume).

In searching around, the best way that I feel to do this is with making different BuildConfig for each environment. This is what I tried:

import java.util.regex.Pattern

buildscript {
    repositories {
        mavenCentral()
    }

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

apply plugin: 'android'

task('increaseVersionCode') << {
    def manifestFile = file("AndroidManifest.xml")
    def pattern = Pattern.compile("versionCode=\"(\\d+)\"")
    def manifestText = manifestFile.getText()
    def matcher = pattern.matcher(manifestText)
    matcher.find()
    def versionCode = Integer.parseInt(matcher.group(1))
    def manifestContent = matcher.replaceAll("versionCode=\"" + ++versionCode + "\"")
    manifestFile.write(manifestContent)
}

tasks.whenTaskAdded { task ->
    if (task.name == 'generateReleaseBuildConfig') {
        task.dependsOn 'increaseVersionCode'
    }
}

dependencies {
	compile 'com.android.support:support-v4:19.0.0' 
    compile files('libs/commons-io-2.4.jar',
    	          'libs/google-play-services.jar',
    	          'libs/gson-2.2.4.jar',
    	          'libs/universal-image-loader-1.8.6.jar',
    	          'libs/wakeful-1.0.1.jar')
	compile project(':pulltorefresh_lib')
	compile project(':edgeeffect_lib')
	compile project(':viewpagerindicator_lib')        
}

android {
	buildToolsVersion "18.1.1"
    compileSdkVersion "Google Inc.:Google APIs:18"
    
	defaultConfig { 
       minSdkVersion 14
       targetSdkVersion 18
	}

	buildTypes {
		debug {
			packageNameSuffix ".debug"
		}
		dev.initWith(buildTypes.debug)
		dev {
			buildConfigField "String", "URL_SEARCH", "\"https://dev-search.example.com\";"
			buildConfigField "String", "URL_CONNECT", "\"https://dev-connect.example.com\";"
			buildConfigField "String", "URL_SVC_NEWSLIST", "\"https://dev-mobilenews.example.com/newslist\";"
			buildConfigField "String", "URL_SVC_NEWSDETAIL", "\"https://dev-mobilenews.example.com/newsdetail\";"
			buildConfigField "String", "URL_SVC_REGISTERENDPOINTS", "\"https://dev-mobilenews.example.com/registerendpoints\";"
		}
		prod.initWith(buildTypes.release)
		prod {
			buildConfigField "String", "URL_SEARCH", "\"https://search.example.com\";"
			buildConfigField "String", "URL_CONNECT", "\"https://connect.example.com\";"
			buildConfigField "String", "URL_SVC_NEWSLIST", "\"https://mobilenews.example.com/newslist\";"
			buildConfigField "String", "URL_SVC_NEWSDETAIL", "\"https://mobilenews.example.com/newsdetail\";"
			buildConfigField "String", "URL_SVC_REGISTERENDPOINTS", "\"https://mobilenews.pdc-np-cf.lmig.com/registerendpoints\";"			
		}
	}
  
	sourceSets {
        main {
            manifest.srcFile 'AndroidManifest.xml'
            java.srcDirs = ['src']
            resources.srcDirs = ['src']
            res.srcDirs = ['res']
            assets.srcDirs = ['assets']
        }
    }
}

The problem is that my BuildConfig.java doesn't seem to get the static variables injected, therefore I get errors similar to:

/Users/path/to/project/MainActivity.java:348: error: cannot find symbol
			startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(BuildConfig.URL_SEARCH)));
			                                                                  ^
  symbol:   variable URL_SEARCH
  location: class BuildConfig
/Users/path/to/project/MainActivity.java:359: error: cannot find symbol
			startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse(BuildConfig.URL_CONNECT)));
			                                                                  ^
  symbol:   variable URL_CONNECT
  location: class BuildConfig
/Users/path/to/project/MainActivity.java:600: error: cannot find symbol
			HttpPost httpPost = new HttpPost(BuildConfig.URL_SVC_REGISTERENDPOINTS);
			                                            ^
  symbol:   variable URL_SVC_REGISTERENDPOINTS
  location: class BuildConfig
/Users/path/to/project/service/AlarmNotificationService.java:145: error: cannot find symbol
		String requestUrl = BuildConfig.URL_SVC_NEWSLIST + "?"
		                               ^
  symbol:   variable URL_SVC_NEWSLIST
  location: class BuildConfig
/Users/path/to/project/service/NewsService.java:240: error: cannot find symbol
		String requestUrl = BuildConfig.URL_SVC_NEWSLIST + "?"
		                               ^
  symbol:   variable URL_SVC_NEWSLIST
  location: class BuildConfig
/Users/path/to/project/service/NewsService.java:530: error: cannot find symbol
			HttpPost httpPost = new HttpPost(BuildConfig.URL_SVC_NEWSDETAIL);
			                                            ^
  symbol:   variable URL_SVC_NEWSDETAIL
  location: class BuildConfig
6 errors

My build/source/buildConfig/debug/com/.../BuildConfig.java file contains:

/**
 * Automatically generated file. DO NOT MODIFY
 */
package com....;

public final class BuildConfig {
  public static final boolean DEBUG = Boolean.parseBoolean("true");
  public static final String PACKAGE_NAME = "com.....debug";
  public static final String BUILD_TYPE = "debug";
  public static final String FLAVOR = "";
  public static final int VERSION_CODE = 5;
}

What am I doing wrong?

Please, be sure that you are building "dev" or "prod" variant. There is no BuildConfig definition in default "debug" and "release" variant. In Android Studio, you can select current variant in bottom left corner:

To simplify your build.gradle file, you can define:

buildTypes {
    debug {
        buildConfigField "String", "URL_SEARCH", "\"https://dev-search.example.com\""
        // etc.
    }
    release {
        buildConfigField "String", "URL_SEARCH", "\"https://search.example.com\""
        // etc.      
    }
}

and then just use default "debug" and "release" variants.

At last, delete semicolon (sign: ';') from the value of buildConfigField parameter.

I had same issue and fixed it like below:

buildConfigField 'String', 'BASE_URL', '"https://api.example.com"'

first do

File -> Invalidate Caches/Restart... -> Invalidate and Restart 

then do

Build -> Clean Project

then do

Build - > Rebuild Project 

Just in case that helps somebody else, in my case it was a missing import: import uk.co.yourpackage.yourapp.BuildConfig;

Somehow, nowhere in the doc does it mention you need that include! Made me think it was automatically imported somehow but it ISN'T. not for me at least... So much time lost... Hope that helps another newbie like me!

Try to do

> Build -> Clean Project

then do

> Build - > Rebuild Project

If it doesn't work, try

> File -> Invalidate Caches/Restart... -> Invalidate and Restart

then do

> Build -> Clean Project

then do

> Build - > Rebuild Project

Here is what fixed this for me:

File -> Invalidate Caches/Restart... -> Invalidate and Restart 

If you are modifying your Environment Variables, and they are not reflecting correctly in Android studio try doing:

Build -> Clean Project 
File -> Invalidate Caches/Restart... -> Invalidate and Restart 

I solve this problem as given below in this case Android studio will generate Build Config file itself

File -> Sync Project with Gradle Files

In the project.ext.envConfigFiles array, ensure you set the debug to the right .env file you are using for development

I did all the things in the answers but still didn't work. I solved my problem by changing the package name in the manifest.xml file which still hadn't been updated :

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.example.android">

After trying everything, switching the build variant and selecting Build > Make Project worked for me.

I had similar problem related to build types being setup using .initWith(someotherbuildtype), BuildConfig was not being created properly. I had to switch to the parent build variant and build that first, then the build types that initWith the parent built fine.

In my case, I was expecting the BuildConfig for my new gradle module created. But forgot to add it as a dependency in app: module.

In my case there was an string field resValue "string", "app_name", "MyApp" in strings.xml as well as in product flavours.

I did Invalidate Caches then Rebuild then android studion given the actual error of duplicate resources.

so Invalidate caches -> Rebuild -> Remove string resources which were already in buildconfigfield resvalue worked for me

I was using Android Studio Bumblebee 2021.1.1