19. 코틀린 버튼 이벤트

class MainActivity : AppCompatActivity() {       override fun onCreate(savedInstanceState: Bundle?) {         super.onCreate(savedInstanceState)         setContentView(R.layout.activity_main)   //        val quizStart = findViewById<Button>(R.id.quiz_start);         findViewById<Button>(R.id.quiz_start).setOnClickListener { view ->  onQuizStart(view) }     }       fun onQuizStart(view: View) : Unit {         //퀴즈 데이터베이스에 데이터가 있으면 띄워준다.         //데이터가 존재하지 않으면 없음으로 표시.           val builder = AlertDialog.Builder(this@MainActivity)         builder.setTitle("제목(kotlin)")         builder.setMessage("내용(Kotlin)")           builder.setPositiveButton(android.R.string.yes) { dialog, which ->             Toast.makeText(applicationContext,                 android.R.string.yes, Toast.LENGTH_SHORT).show()         }           builder.setNegativeButton(android.R.string.no) { dialog, which ->             Toast.makeText(applicationContext,                 android.R.string.no, Toast.LENGTH_SHORT).show()         }           builder.setNeutralButton("Maybe") { dialog, which ->             Toast.makeText(applicationContext,                 "Maybe", Toast.LENGTH_SHORT).show()         }           builder.show()     }       fun onQuizCreate(view: View) : Unit {         //퀴즈 데이터가 있으면 불러오고, 없으면 빈칸으로 표시.           val builder = AlertDialog.Builder(ContextThemeWrapper(this@MainActivity, R.style.Theme_AppCompat_Light_Dialog))         builder.setTitle("제목(kotlin)2")         builder.setMessage("내용(Kotlin)2")           builder.show();     }       fun onQuizCreate2(view : View) : Unit {         var temp:String = "";           when(view.id){             R.id.quiz_start -> temp = "quiz_start";             R.id.quiz_create -> temp = "quiz_create";         }     } }

1. findViewById<Button>(R.id.quiz_start).setOnClickListener { view ->  onQuizStart(view) } 리스너 대기(이벤트)

2. onQuizCreate xml activity에서 접근, 매개변수는 view를 받아야 한다.

3. onQuizCreate2 xml activity에서 접근, 다수의 이벤트를 한번에 실행시켜, id로 판별

 

<?xml version="1.0" encoding="utf-8"?>   <LinearLayout     xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:tools="http://schemas.android.com/tools"     xmlns:app="http://schemas.android.com/apk/res-auto"     android:layout_width="match_parent"     android:layout_height="match_parent"     android:orientation="vertical"     android:gravity="center_vertical"     android:layout_weight="1" >       <Button             android:id="@+id/quiz_start"             android:layout_width="@dimen/button_width_size"             android:layout_height="wrap_content"             android:layout_gravity="center_horizontal"             android:layout_marginBottom="10dp"             android:textSize="@dimen/button_text_size"             android:text="퀴즈 시작"     />       <Button             android:id="@+id/quiz_create"             android:layout_width="@dimen/button_width_size"             android:layout_height="wrap_content"             android:layout_gravity="center_horizontal"             android:textSize="@dimen/button_text_size"             android:text="퀴즈 만들기"             android:onClick="onQuizCreate"     />   </LinearLayout>