Android Learning notes-Generate 40 list items with Baseadapter

RT;

Main.xml

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<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"               android:orientation="vertical"               android:layout_width="match_parent"               android:layout_height="match_parent"         >     <ListView             android:id="@+id/myList"             android:layout_width="match_parent"             android:layout_height="match_parent"             /> </LinearLayout>

Myactivity.java

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public class MyActivity extends Activity {     /**      * Called when the activity is first created.      */    ListView myList;     public void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         setContentView(R.layout.main);         myList=(ListView)findViewById(R.id.myList);         BaseAdapter adapter =new BaseAdapter() {             @Override             public int getCount() {                 //指定一共包含40个选项                 return 40;             }            @Override             public Object getItem(int i) {                 return null;  //To change body of implemented methods use File | Settings | File Templates.             } //重写该方法，该方法的返回值将作为列表项的ID             @Override             public long getItemId(int i) {                 return i;  //To change body of implemented methods use File | Settings | File Templates.             }            @Override             public View getView(int i, View view, ViewGroup viewGroup) {           //创建一个LinerarLayout，并向其中添加两个组件                 LinearLayout line=new LinearLayout(MyActivity.this);                 line.setOrientation(0);                 ImageView image=new ImageView(MyActivity.this);                 image.setImageResource(R.drawable.ic_launcher);                 TextView text=new TextView(MyActivity.this);                 text.setText("第"+(i+1)+"个列表项");                 text.setTextSize(20);                 text.setTextColor(Color.RED);                 line.addView(image);                 line.addView(text);                 //返回LinearLayout实例                 return line;             }         };         myList.setAdapter(adapter);     } }

Effect

To create a Badeadapter object, you need to override the following 4 methods to extend the object

* GetCount (): The return value of this method controls how many list items the adapter will contain.

* GetItem (): The return value of the method determines the contents of the list item at postion.

* GETITEMID (int i): The return value of the method determines the ID of the list item at postion.

* GetView (int i,view view,viewgroup viewgroup): The return value of this method determines the list item component in section I