How can I access a BuildConfig value in my AndroidManifest.xml file?
Replace
buildConfigField "long", "FACEBOOK_APP_ID", FACEBOOK_APP_ID
with
resValue "string", "FACEBOOK_APP_ID", FACEBOOK_APP_ID
then rebuild your project (Android Studio -> Build -> Rebuild Project).
The two commands both produce generated values - consisting of Java constants in the first case, and Android resources in the second - during project builds, but the second method will generate a string
resource value that can be accessed using the @string/FACEBOOK_APP_ID
syntax. This means it can be used in the manifest as well as in code.
note: when you use resValue
the value can accidentally be overridden by the strings resource file (e.g. for another language)
To get a true constant value that you can use in the manifest and in java-code, use both manifestPlaceholders
and buildConfigField
: e.g.
android {
defaultConfig {
def addConstant = {constantName, constantValue ->
manifestPlaceholders += [ (constantName):constantValue]
buildConfigField "String", "${constantName}", "\"${constantValue}\""
}
addConstant("FACEBOOK_APP_ID", "xxxxx")
}
access in the manifest file:
<meta-data android:name="com.facebook.sdk.ApplicationId" android:value="${FACEBOOK_APP_ID}"/>
from java:
BuildConfig.FACEBOOK_APP_ID
If the constant value needs to be buildType-specific, the helper addConstant
needs to be tweaked (to work with groovy closure semantics), e.g.,
buildTypes {
def addConstantTo = {target, constantName, constantValue ->
target.manifestPlaceholders += [ (constantName):constantValue]
target.buildConfigField "String", "${constantName}", "\"${constantValue}\""
}
debug {
addConstantTo(owner,"FACEBOOK_APP_ID", "xxxxx-debug")
}
release {
addConstantTo(owner,"FACEBOOK_APP_ID", "xxxxx-release")
}
Another way to access Gradle Build Config values from your AndroidManifest.xml is through placeholders like this:
android {
defaultConfig {
manifestPlaceholders = [ facebookAppId:"someId..."]
}
productFlavors {
flavor1 {
}
flavor2 {
manifestPlaceholders = [ facebookAppId:"anotherId..." ]
}
}
}
and then in your manifest:
<meta-data android:name="com.facebook.sdk.ApplicationId" android:value="${facebookAppId}"/>
See more details here: https://developer.android.com/studio/build/manifest-build-variables.html
(Old link just for reference: http://tools.android.com/tech-docs/new-build-system/user-guide/manifest-merger)
Access build.gradle properties in your manifest as in following example:
For example you have a property "applicationId" in your build.gradle and you want to access that in your AndroidManifest:
Access "applicationId" in AndroidManifest:
<receiver
android:name="com.google.android.gms.gcm.GcmReceiver"
android:exported="true"
android:permission="com.google.android.c2dm.permission.SEND">
<intent-filter>
<action android:name="com.google.android.c2dm.intent.RECEIVE" />
<category android:name="${applicationId}" />
</intent-filter>
</receiver>
Similarly, we can create string resources for other constants and access them in code files as simple as:
context.getString(R.string.GCM_SENDER_ID);