DailyDictionary Mars Study

1.spinner

Activity

public class MainActivity extends AppCompatActivity {private Spinner spinner;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        spinner=(Spinner)findViewById(R.id.spinner);        ArrayAdapter<CharSequence> adapter=ArrayAdapter.createFromResource(                this,R.array.arrar,android.R.layout.simple_spinner_item);        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);        spinner.setAdapter(adapter);        spinner.setPrompt("Spinner");        spinner.setOnItemSelectedListener(new SpinnerOnSelectedListener());    }     class SpinnerOnSelectedListener implements AdapterView.OnItemSelectedListener{         @Override         public void onItemSelected(AdapterView<?> adapterView, View view,int position,long id){             String selected=adapterView.getItemAtPosition(position).toString();             Log.d("1",selected);         }         @Override         public void onNothingSelected(AdapterView<?>adapterView){             System.out.println("nothingselected");         }     }

stings

 <string name="spinner">spinner</string>    <string-array name="arrar">        <item>Earth</item>        <item>Mars</item>        <item>Moon</item>    </string-array>

Mars Java4Android

面向对象+继承+抽象+super

抽象Person父类 

public abstract class Person {String name;int age;Person(){System.out.println("Pserson函数");} Person(String name,int age){System.out.println("Person函数 "+"Test输入"+name+"  "+age);}void introduse(){System.out.println("introduce");}abstract void eat();}

子类Chinese

public  class Chinese extends Person{Chinese(){super();System.out.println("Chinese构造函数");} Chinese(String name,int age){super(name,age); }void eat(){System.out.println("Chinese eat");}}

测试Test

public class Test {  public static void main(String args[]){Chinese chinese=new Chinese();chinese.eat();Chinese chin=new Chinese("2",1);chinese.introduse();}  }

Pserson函数
Chinese构造函数
Chinese eat
Person函数 Test输入2  1
introduce

接口interface

接口:Wifi,Usb,

Phone实现WIFi和USB接口 ：implements

Test调用Phone

public interface Wifi {void open();void close();}

public interface Usb {void write();void read();}

public class Phone implements Usb,Wifi{//继承两个接口

public void write(){System.out.println("Usb write");}public void read(){System.out.println("Usb read");}public void open(){System.out.println("Wifi open");}public void close(){System.out.println("Wifi close");}}

public class Test {public static void main(String args[]){Phone p=new Phone();p.write();Usb pe=new Phone();//向上转型pe.read();Phone w=new Phone();w.open();Wifi wi=new Phone();//向上转型wi.close();}}

工厂方法模式

工厂类

public class PrinterFactory {public static Printer getPrinter(int flag){Printer printer=null;if(flag==1){printer=new HpPrinter();}else if (flag==2){printer=new CaPrinter(); }else if(flag==3){printer =new QhPrinter();}return printer;}}

MarsforAndroid 22

public static void main(String[] args) {// TODO Auto-generated method stubint flag=2;Printer printer=PrinterFactory.getPrinter(flag);printer.Open();printer.Print("s");printer.Close();

public class CaPrinter extends Printer{void Close(){this.Clean();super.Close();}void Clean(){System.out.println("Ca  Clean");}}

public class Printer {void Open(){System.out.println("open");}void Close(){System.out.println("close");}void Print(String s){System.out.println("print   "+s);}}