Android Api 24 can't find sources
<p>I have this grade file:</p>

<pre><code>//ext.support_library_version = '24.0.0'

    android {
        compileSdkVersion 24
        buildToolsVersion '24.0.0'

        defaultConfig {
            applicationId "---"
            minSdkVersion 21
            targetSdkVersion 24
            versionCode 1
            versionName "1.0"
        }
    ...
    }
</code></pre>

<p>But then when i try to open any android related class, it says i haven't got sources for api24, even tho the <code>buildToolsVersion '24.0.0'</code> is installed. Any idea why?</p>