[Android] Check Permissions

안드로이드 여러가지 권한을 요청하고 처리하는 코드

• AndroidManifest.xml

  <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
  <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
  <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
  <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>

• 선언

  private val reuqestCodePermission = 101
  private val keyPermissionsRequestCount = "KEY_PERMISSIONS_REQUEST_COUNT"
  private val maxNumberReqeustPermissions = 4
  private val permissions = Arrays.asList(
  	Manifest.permission.READ_EXTERNAL_STORAGE,
  	Manifest.permission.WRITE_EXTERNAL_STORAGE,
  	Manifest.permission.ACCESS_FINE_LOCATION,
  	Manifest.permission.ACCESS_COARSE_LOCATION
  )

• onCreate()

  override fun onCreate(savedInstanceState: Bundle?) {
      ...
      ...
      savedInstanceState?.let {permissionRequestCount = it.getInt(KEY_PERMISSIONS_REQUEST_COUNT, 0)}
      ...
      requestPermissions()
      ...
  }

• 퍼미션 체크

  private fun checkAllPermissions(): Boolean {
  var hasPermissions = true
      for (permission in permissions) {
          hasPermissions = hasPermissions and isPermissionGranted(permission)
      }
  	return hasPermissions
  }

• 퍼미션 요청

  private fun requestPermissionsIfNecessary() {
  	if (!checkAllPermissions()) {
  		if (permissionRequestCount < MAX_NUMBER_REQUEST_PERMISSIONS) {
  			permissionRequestCount += 1
  			ActivityCompat.requestPermissions(
  				this,
  				permissions.toTypedArray(),
  				REQUEST_CODE_PERMISSIONS
  			)
  		} else {
  			Toast.makeText(this,"Go to Settings",Toast.LENGTH_LONG).show()
  		}
  	}
  }

• onSaveInstanceState()

  override fun onSaveInstanceState(outState: Bundle) {
  	super.onSaveInstanceState(outState)
  	outState.putInt(KEY_PERMISSIONS_REQUEST_COUNT, permissionRequestCount)
  }