make sure there is a v7 directory in your sdk, I thought having the 'Android Support Library' (in Extras) was sufficient. Turns out I was missing the 'Local Maven repository for Support Libraries (extras;android;m2repository)' Studio found that actually and fixed the gradle dependencies. using gradle to build then worked.
$ cat app/build.gradle
apply plugin: 'com.android.application'
android {
compileSdkVersion 23
buildToolsVersion "23.0.2"
defaultConfig {
applicationId "pat.example.com.gdbdemo"
minSdkVersion 15
targetSdkVersion 23
versionCode 1
versionName "1.0"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:appcompat-v7:23.2.1'
}