kotlin编《第一行代码》

Posted 2020-10-01 霞腾龙升

一、alertdialog

java：

　　AlertDialog.Builder dialog=new AlertDialog.Builder(MainActivity.this);

　　dialog.setTitle("This is Dialog");

　　dialog.setMessage("Something important.");

　　dialog.setCancelable(false);

　　dialog.setPositiveButton("OK",new DialogInterface.OnClickListener(){

　　　　public void onClick(DialogInterface dialog,int which){

　　　　}

　　});

　　dialog.setNegativeButton("Cancel",new DialogInterface.OnclickListener(){

　　　　public void onClick(DialogInterface diailog,int which){

　　　　}

　　});

　　dialog.show();

kotlin:

fun alert(v:View?){
　　val dialog1=AlertDialog.Builder(this)
　　dialog1.setTitle("This is Dialog")
　　dialog1.setMessage("Something important.")
　　dialog1.setCancelable(false)
　　dialog1.create().show()
}

二、listview

java：

　　<ListView
　　　　android:id="@+id/list_view"
　　　　android:layout_width="match_parent"
　　　　android:layout_height="match_parent"

　　/>

　　private String[] data={"Apple","Banana","Orange","Watermelon","Pear","Grape","Pineapple",
　　　　"Strawberry","Cherry","Mango","Apple","Banana","Orange","Watermelon",
　　　　"Pear","Grape","Pineapple","Strawberry","Cherry","Mango"};
　　@Override
　　protected void onCreate(Bundle savedInstanceState) {
　　　　super.onCreate(savedInstanceState);
　　　　setContentView(R.layout.activity_main);
　　　　ArrayAdapter<String> adapter=new ArrayAdapter<String>(
　　　　MainActivity.this,R.layout.abc_action_menu_item_layout,data);
　　　　ListView listView=(ListView)findViewById(R.id.list_view);
　　　　listView.setAdapter(adapter);
　　}

kotlin：

　　private val data = arrayOf("Apple", "Banana", "Orange", "Watermelon", "Pear", "Grape", "Pineapple",

　　　　 "Strawberry", "Cherry", "Mango", "Apple", "Banana", "Orange", "Watermelon",

　　　　"Pear", "Grape", "Pineapple", "Strawberry", "Cherry", "Mango")
　　override fun onCreate(savedInstanceState: Bundle?) {
　　val adapter = ArrayAdapter(
　　　　[email protected], R.layout.abc_action_menu_item_layout, data)
　　listView.adapter = adapter

}