Android 6.0 multiple permissions

Question

I know that Android 6.0 has new permissions and I know I can call them with something like this

if (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) !=
    PackageManager.PERMISSION_GRANTED) {
    ActivityCompat.requestPermissions(this,
        new String[] { 
            Manifest.permission.WRITE_EXTERNAL_STORAGE
        }, PERMISSION_WRITE_STORAGE);
}

Today I saw a Google app which needs 3 permissions: contacts, sms and camera. It's making a page 1-3 and calls them all together at the same time to activate.

Can anybody tell me how I can call 4 permissions to activate at the same time like sms, camera, contacts and storage?

Example (forgot the name of the google app :( )
The app needs sms,contacts and camera

the app asked me (and made a dialog page1-3) activate sms, activate contacts and then camera. So this google app was calling all 3 required permissions together and my question is how can i achive the same ?

Answer 1

After seeing all the long and complex answers. I want post this answer.

RxPermission is widely used library now for asking permission in one line code.

RxPermissions rxPermissions = new RxPermissions(this);
rxPermissions
.request(Manifest.permission.CAMERA,
         Manifest.permission.READ_PHONE_STATE)
.subscribe(granted -> {
    if (granted) {
       // All requested permissions are granted
    } else {
       // At least one permission is denied
    }
});

add in your build.gradle

allprojects {
    repositories {
        ...
        maven { url 'https://jitpack.io' }
    }
}

dependencies {
    implementation 'com.github.tbruyelle:rxpermissions:0.10.1'
    implementation 'com.jakewharton.rxbinding2:rxbinding:2.1.1'
}

Isn't this easy?