title: Cannot Resolve symbol ActivityCompat
body: <p>Cannot resolve symbol 'ActivityCompat' 
  I am trying to send SMS through my application.
  I have added uses permission on AndroidManifest.xml as well</p>
  
  <p>ActivityCompat is not resolving help me out.</p>
  
  <p>complie Sdk version is 25</p>
  
  <pre><code>    try {
          SmsManager smsManager = SmsManager.getDefault();
          smsManager.sendTextMessage(phoneNo, null, message, null, null);
          if (ContextCompat.checkSelfPermission(sendSMS2.this, Manifest.permission.SEND_SMS)
                  != PackageManager.PERMISSION_GRANTED) {
              // Permission is not granted
              // Ask for permision
              ActivityCompat.requestPermissions(this,new String[] { Manifest.permission.SEND_SMS}, 1);
          }
  </code></pre>
  
  <p>here is the build.gradle </p>
  
  <pre><code>apply plugin: 'com.android.application'
  
  android {
      compileSdkVersion 25
      buildToolsVersion '25.0.0'
  
      defaultConfig {
          applicationId "com.example.somme.testproj2"
          minSdkVersion 19
          targetSdkVersion 25
          versionCode 1
          versionName "1.0"
      }
      buildTypes {
          release {
              minifyEnabled false
              proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
          }
      }
  }
  
  dependencies {
      compile fileTree(include: ['*.jar'], dir: 'libs')
      compile 'com.android.support:design:25.0.0'
      compile 'com.android.support.constraint:constraint-layout:1.0.2'
      compile 'com.android.support:appcompat-v7:+'
  
  }
  </code></pre>