android編程舉例4

1、表格布局：Main.xml<?xml version="1.0" encoding="utf-8"?> <TableLayout android:id="+id/TableLayout01" android:layout_width="fill_parent" android:layout_height="fill_parent" xmlns:android="<TableRow android:id="+id/TableRow01" and

2、roid:layout_width="wrap_content" android:layout_height="wrap_content"><TextView android:id="+id/label" android:layout_height="wrap_content" android:layout_width="160dip"android:gravity="right" android:text="用戶名：" android:pad

3、ding="3dip" ></TextView><EditText android:id="+id/entry" android:layout_height="wrap_content" android:layout_width="160dip"android:padding="3dip" ></EditText></TableRow><TableRow android:id="+id/TableRow02" and

4、roid:layout_width="wrap_content" android:layout_height="wrap_content"><Button android:id="+id/ok" android:layout_height="wrap_content" android:padding="3dip" android:text="確認"></Button><Button android:id="+id/Button02

5、" android:layout_width="wrap_content" android:layout_height="wrap_content" android:padding="3dip" android:text="取消"></Button></TableRow></TableLayout> 功能描述：主界面上有一個“登錄”按鈕，點擊“登錄”按鈕后打開一個新的Activity；新的Activity上面有輸入用戶名和密碼的控件，在用戶關閉這個Activity

6、后，將用戶輸入的用戶名和密碼傳遞到主界面中。 編程要點：主界面的Activity命名為MainActivity；啟動新的Activity命名為UserLoginActivity；分別使用顯示啟動和隱式啟動的方式，啟動新的Activity；用戶名中不能出現(xiàn)“”符號，同時長度不超過12個字符；密碼使用密碼文本顯示方式，即顯示為“*”，同時只能為數(shù)字； 返回的用戶名和密碼要以Toast的方式顯示出來； MainActivity和UserLoginActivity中各個生命周期的回調函數(shù)中要以Log.i方式顯示日志信息。兩個布局xml代碼類似上面的布局，故省略，自己模仿MainActivity.jav

7、apublic class MainActivity extends Activity protected int SUBACTIVITY1 = 1;/唯一標示子activity標識碼private static String TAG = "MainActivity"/用來在運行時顯示activity日志，即上面要求的第五條Button button1,button2;public void onCreate(Bundle savedInstanceState) super.onCreate(savedInstanceState);setContentView(R.layo

8、ut.main);Log.i(TAG, "(1) onCreate()");/日志上顯示onCreate（）button1 = (Button) this.findViewById(R.id.button1);button2 = (Button) this.findViewById(R.id.button2);button1.setOnClickListener(new View.OnClickListener() public void onClick(View v) Intent intent = new Intent(MainActivity.this,UserLog

9、inActivity.class);Toast.makeText(getApplicationContext(), "顯示啟動", Toast.LENGTH_SHORT).show();startActivityForResult(intent, SUBACTIVITY1); );button2.setOnClickListener(new View.OnClickListener()public void onClick(View v) Intent intent = new Intent("cn.test.nchu");Toast.makeText(

10、getApplicationContext(), "隱式啟動", Toast.LENGTH_SHORT).show();startActivityForResult(intent, SUBACTIVITY1););protected void onActivityResult(int requestCode, int resultCode, Intent data) super.onActivityResult(requestCode, resultCode, data);if (resultCode = RESULT_OK) Uri uriData = data.getD

11、ata();Toast.makeText(getApplicationContext(), uriData.toString(),Toast.LENGTH_SHORT).show(); else Toast.makeText(getApplicationContext(), "用戶名和密碼為空", Toast.LENGTH_SHORT).show();/可視生命周期開始時被調用，對用戶界面進行必要的更改 public void onStart() super.onStart(); Log.i(TAG, "(2) onStart()"); /在onStar

12、t()后被調用，用于恢復onSaveInstanceState()保存的用戶界面信息 public void onRestoreInstanceState(Bundle savedInstanceState) super.onRestoreInstanceState(savedInstanceState); Log.i(TAG, "(3) onRestoreInstanceState()"); /在活動生命周期開始時被調用，恢復被onPause()停止的用于界面更新的資源 public void onResume() super.onResume(); Log.i(TAG,

13、 "(4) onResume()"); / 在onResume()后被調用，保存界面信息 public void onSaveInstanceState(Bundle savedInstanceState) super.onSaveInstanceState(savedInstanceState); Log.i(TAG, "(5) onSaveInstanceState()"); /在重新進入可視生命周期前被調用，載入界面所需要的更改信息 public void onRestart() super.onRestart(); Log.i(TAG, &quo

14、t;(6) onRestart()"); /在活動生命周期結束時被調用，用來保存持久的數(shù)據或釋放占用的資源。 public void onPause() super.onPause(); Log.i(TAG, "(7) onPause()"); /在可視生命周期結束時被調用，一般用來保存持久的數(shù)據或釋放占用的資源 public void onStop() super.onStop(); Log.i(TAG, "(8) onStop()"); /在完全生命周期結束時被調用，釋放資源，包括線程、數(shù)據連接等 public void onDestroy

15、() super.onDestroy(); Log.i(TAG, "(9) onDestroy()"); UserLoginActivity.javapublic class UserLoginActivity extends Activity EditText username,password;Button submit,reset;private static String TAG = "MainActivity"protected void onCreate(Bundle savedInstanceState) / TODO Auto-gener

16、ated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.login); Log.i(TAG, "(1) onCreate()");username=(EditText)this.findViewById(R.id.username);password=(EditText)this.findViewById(R.id.password);submit=(Button)this.findViewById(R.id.submit);reset=(Button)this.findViewB

17、yId(R.id.reset);username.setFocusable(true);username.setOnKeyListener(new OnKeyListener()public boolean onKey(View v, int keyCode, KeyEvent event) / TODO Auto-generated method stubint unicodeChar = event.getUnicodeChar();if(unicodeChar= 64)return true;else return false;);submit.setOnClickListener(ne

18、w View.OnClickListener() public void onClick(View v) / TODO Auto-generated method stubString name =username.getText().toString();String pass=password.getText().toString();String uriString="用戶名："+name+"密碼："+pass; Uri data = Uri.parse(uriString); Intent result = new Intent(null, da

19、ta); setResult(RESULT_OK, result);finish(););reset.setOnClickListener(new View.OnClickListener() public void onClick(View v) / TODO Auto-generated method stubsetResult(RESULT_CANCELED, null);finish(););下面和MainActivity.java中的一樣都是設置activity生命周期在log中顯示AndroidManifest.xml<?xml version="1.0"

20、 encoding="utf-8"?><manifest xmlns:android=" package="cn.test.nchu" android:versionCode="1" android:versionName="1.0"> <uses-sdk android:minSdkVersion="8" /> <application android:icon="drawable/icon" android:label=&qu

21、ot;string/app_name"> <activity android:name=".MainActivity" android:label="string/app_name"> <intent-filter> <action android:name="ent.action.MAIN" /> <category android:name="ent.category.LAUNCHER" /> </

22、intent-filter> </activity><activity android:name="cn.test.nchu.UserLoginActivity" >/顯式啟動要加的activity <intent-filter> <action android:name="cn.test.nchu" />/隱式啟動，名字和MainActivity.java中的隱式啟動里的名字一樣 <category android:name="ent.category.DEFA

23、ULT" /> </intent-filter> </activity> </application></manifest>編程建立一個簡單的進程內服務，實現(xiàn)比較兩個整數(shù)大小的功能。服務提供IntCompare(Int, Int)函數(shù)，輸入兩個整數(shù)，輸出較大的整數(shù)。 主界面的Activity命名為MainActivity；提供兩個EditText，分別輸入兩個整數(shù)；提供一個Botton，啟動比較過程；提供一個TextView，顯示較大的整數(shù)；分別使用啟動方式和綁定方式使用Service；分別使用Handle和AsyncTask更新

24、TextView中的內容。啟動方式MainActivity.javapublic class MainActivity extends Activity public static int maxNum;public static Handler handler=new Handler();private static TextView result=null;private static Button compare=null;private static Button reset=null;private static EditText one=null;private static Ed

25、itText two=null;public static void UpdateGUI(int refreshDouble)maxNum=refreshDouble;handler.post(RefreshLable); private static Runnable RefreshLable=new Runnable()public void run() result.setText(String.valueOf(maxNum); public void onCreate(Bundle savedInstanceState) final Bundle mybundle=new Bundle

26、(); super.onCreate(savedInstanceState); setContentView(R.layout.main); final Intent intent=new Intent(MainActivity.this,CompareService.class); result=(EditText)findViewById(R.id.result); compare=(Button)findViewById(Rpare); reset=(Button)findViewById(R.id.reset); one=(EditText)findViewById(R.id.one)

27、; two=(EditText)findViewById(R.id.two); compare.setOnClickListener(new OnClickListener() public void onClick(View v) mybundle.putString("one", one.getText().toString(); mybundle.putString("two", two.getText().toString(); intent.putExtras(mybundle); startService(intent); ); reset.

28、setOnClickListener(new OnClickListener() public void onClick(View v) one.setText(null); two.setText(null); result.setText(null); ); CompareService.javapublic class CompareService extends Service private Thread workThread;Bundle bundle=null;int one=0,two=0;public void onCreate() super.onCreate(); wor

29、kThread = new Thread(null,backgroudWork,"WorkThread");public void onStart(Intent intent, int startId) super.onStart(intent, startId); bundle=intent.getExtras(); String c1=bundle.getString("one"); String c2=bundle.getString("two"); if(!c1.toString().equals("")&

30、amp;&!c2.toString().equals("") one=Integer.parseInt(c1); two=Integer.parseInt(c2); if (!workThread.isAlive() workThread.start(); public IBinder onBind(Intent intent) return null;private Runnable backgroudWork = new Runnable()public void run() int randomDouble =IntCompare(one,two);MainA

31、ctivity.UpdateGUI(randomDouble);stopSelf();int IntCompare(int a,int b)if(a>=b)return a;elsereturn b;這樣并沒有完，還要在AndroidManifest.xml中加入service名字，如<application 。（和前面的AndroidManifest.xml代碼相同） <service android:name=".CompareService" ></service></application>綁定啟動MainActivi

32、ty.Javapublic class MainActivity extends Activity private boolean isBound = false;private CompareService compareService;int a=0,b=0; public void onCreate(Bundle savedInstanceState) super.onCreate(savedInstanceState); setContentView(R.layout.main); final TextView result=(TextView)findViewById(R.id.re

33、sult); Button compare=(Button)findViewById(Rpare); Button reset=(Button)findViewById(R.id.reset); final EditText one=(EditText)findViewById(R.id.one); final EditText two=(EditText)findViewById(R.id.two); if(!isBound)Intent serviceIntent=new Intent(MainActivity.this,CompareService.class);bindService(serviceIntent,mConnection,Context.BIND_AUTO_CREATE);isBound=true; compare.setOnClickListener(new OnClickList