Android studio devolpment error

Android studio gradle error:

error:  android studio打开项目后一直Gradle:Resolve dependecies 'app_XXAPk'

1. my method:

Add in build.gradle:

allprojects {
    repositories {
++        maven { url 'http://repo1.maven.org/maven2' }
        jcenter()
    }
}

2.

buildscript {
repositories {
maven { url 'http://maven.oschina.net/content/groups/public/' }
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:1.1.0'

// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}

allprojects {
repositories {
maven { url 'http://maven.oschina.net/content/groups/public/' }
jcenter()
}
}