Statically typed programming language for the JVM, Android and the browser

inline fun Activity.toast(message : Int) {
   Toast.makeText(this, message, Toast.LENGTH_SHORT).show()
 }

when(x) {
1-> {}
2-> {}
}

switch(x) {
case 1:
 break;
case 2:
 break;
default:
 break;
}

var a: String? = "abc" 

dependencies {
    classpath 'com.android.tools.build:gradle:2.2.3'
    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version" //这是需要你加入的
  }

allprojects {
  repositories {
    jcenter()
    maven {url 'https://dl.bintray.com/jetbrains/anko'} //这是你需要加入的
  }
}

compile "org.jetbrains.anko:anko-sdk15:0.9.1" // So here it's 15 too
  compile "org.jetbrains.anko:anko-appcompat-v7:0.9.1"
  compile "org.jetbrains.anko:anko-design:0.9.1"
  compile "org.jetbrains.anko:anko-recyclerview-v7:0.9.1"

class MainActivity : AppCompatActivity(), MainContract.View {
  override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
  }
}

relativeLayout {

      var mToolbar =
      toolbar(R.style.Base_ThemeOverlay_AppCompat_Dark_ActionBar) {
        id = ID_TOOLBAR
        title = "登录"
        backgroundColor = ContextCompat.getColor(this@MainActivity, R.color.colorPrimary)

        popupTheme = R.style.Base_ThemeOverlay_AppCompat_Light
        inflateMenu(R.menu.main)

        setNavigationIcon(R.mipmap.img_back_white)

        onMenuItemClick {
          menuItem ->
          val itemId = menuItem!!.itemId
          when (itemId) {
            R.id.menu_main -> {
              toast(R.string.main_toast)
            }
          }
          false
          }

        lparams {
          width = matchParent
          height = wrapContent
        }

        setNavigationOnClickListener {
          finish()
        }
      }

      var mUserEdit = editText {
        id = ID_USER_EDIT
        hint = "请输入同户名"
        maxLines=1

        lparams {
          width = matchParent
          height = wrapContent
          margin=dip(8)
          centerInParent()
        }
      }

      var mPsdEdit = editText {
        id= ID_PSD_EDIT
        hint="请输入密码"
        maxLines=1
        maxWidth = 16

        lparams {
          width = matchParent
          height = wrapContent
          margin = dip(8)
          below(ID_USER_EDIT)
        }
      }


      var mButton = button("登录") {
        id= ID_BTN_LOGIN

        onClick {
          var username = mUserEdit.text.toString()
          var password = mPsdEdit.text.toString()

          mPresenter!!.login(username,password)
        }

        lparams {
          width= matchParent
          height = wrapContent
          margin = dip(8)
          below(ID_PSD_EDIT)
        }
      }
    }

companion object static {
    val ID_TOOLBAR: Int = 1
    val ID_USER_EDIT: Int = 2
    val ID_PSD_EDIT: Int = 3
    val ID_BTN_LOGIN: Int = 4
  }

interface BaseView<T> {
  fun setPresenter(presenter: T)
}

interface BasePresenter

interface MainContract {
  interface View : BaseView<Presenter> {
    fun login()
    fun loginNUll()
  }

  interface Presenter : BasePresenter {
    fun login(username: String, password: String)
  }
}

public class MainPresenter implements MainContract.Presenter {

  private MainContract.View mView;

  public MainPresenter(MainContract.View view) {
    mView = view;
    mView.setPresenter(this);
  }

  @Override
  public void login(String username, String password) {
    if (TextUtils.isEmpty(username) || TextUtils.isEmpty(password)) {
      mView.loginNUll();
      return;
    }
    mView.login();
  }
}

var mPresenter : MainContract.Presenter? = null

override fun setPresenter(presenter: MainContract.Presenter) {
  mPresenter = presenter!!
}

override fun loginNUll() {
  toast("用户名密码不得为空")
}

override fun login() {
  toast("执行登录逻辑...")
}