Android开发 常用代码片段

1、查看是否有存储卡插入 

1	String status=Environment.getExternalStorageState();

2

3	if ( status.equals ( Enviroment.MEDIA_MOUNTED ) )

4

{

5

说明有SD卡插入

6

}

2、让某个Activity透明 

1	OnCreate中不设Layout

2

3	this.setTheme(R.style.Theme_Transparent);

4

5	以下是Theme_Transparent的定义（注意transparent_bg是一副透明的图片）

3、在屏幕元素中设置句柄  

 使用Activity.findViewById来取得屏幕上的元素的句柄.使用该句柄您可以设置或获取任何该对象外露的值.

1	TextView msgTextView = (TextView)findViewById(R.id.msg);

2

3	msgTextView.setText(R.string.push_me);

4、发送短信

1	String body=”this is mms demo”;

2

3	Intent mmsintent = new Intent(Intent.ACTION_SENDTO, Uri.fromParts(”smsto”, number, null));

4

5	mmsintent.putExtra(Messaging.KEY_ACTION_SENDTO_MESSAGE_BODY, body);

6	mmsintent.putExtra(Messaging.KEY_ACTION_SENDTO_COMPOSE_MODE, true);

7	mmsintent.putExtra(Messaging.KEY_ACTION_SENDTO_EXIT_ON_SENT, true);

8

9	startActivity(mmsintent);

5、发送彩信

01	StringBuilder sb = new StringBuilder();

02

03	sb.append(”file://”);

04

05	sb.append(fd.getAbsoluteFile());

06

07	Intent intent = new Intent(Intent.ACTION_SENDTO, Uri.fromParts(”mmsto”, number,null));

08

09	// Below extra datas are all optional.

10	intent.putExtra(Messaging.KEY_ACTION_SENDTO_MESSAGE_SUBJECT, subject);

11	intent.putExtra(Messaging.KEY_ACTION_SENDTO_MESSAGE_BODY, body);

12	intent.putExtra(Messaging.KEY_ACTION_SENDTO_CONTENT_URI, sb.toString());

13	intent.putExtra(Messaging.KEY_ACTION_SENDTO_COMPOSE_MODE, composeMode);

14	intent.putExtra(Messaging.KEY_ACTION_SENDTO_EXIT_ON_SENT, exitOnSent);

15

16	startActivity(intent);

6、显示toast

1	Toast.makeText(this._getApplicationContext(), R.string._item, Toast.LENGTH_SHORT).show();

7、发送Mail

1	mime = “img/jpg”;

2

3	shareIntent.setDataAndType(Uri.fromFile(fd), mime);

4

5	shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(fd));

6

7	shareIntent.putExtra(Intent.EXTRA_SUBJECT, subject);

8

9	shareIntent.putExtra(Intent.EXTRA_TEXT, body);

8、注册一个BroadcastReceiver

01	registerReceiver(mMasterResetReciever, newIntentFilter(”OMS.action.MASTERRESET”));

02

03	private BroadcastReceiver mMasterResetReciever = new BroadcastReceiver()

04

{

05	public void onReceive(Context context, Intent intent)

06

{

07	String action = intent.getAction();

08

09	if (”oms.action.MASTERRESET”.equals(action) )

10

{

11	RecoverDefaultConfig();

12

}

13

}

14

};

9、定义ContentObserver，监听某个数据表

01	private ContentObserver mDownloadsObserver = newDownloadsChangeObserver(Downloads.CONTENT_URI);

02

03	private class DownloadsChangeObserver extends ContentObserver

04

{

05	public DownloadsChangeObserver(Uri uri)

06

{

07	super(new Handler());

08

}

09

10

@Override

11	public void onChange(boolean selfChange) {}

12

13

}

10、获得 手机UA 

1	public String getUserAgent()

2

{

3	String user_agent = ProductProperties.get(ProductProperties.USER_AGENT_KEY,null);

4

5	return user_agent;

6

}

11、清空手机上cookie 

1	CookieSyncManager.createInstance (getApplicationContext() );

2

3	CookieManager.getInstance().removeAllCookie();

12、建立GPRS连接 

01	//Dial the GPRS link.

02	private boolean openDataConnection()

03

{

04	// Set up data connection.

05	DataConnection conn = DataConnection.getInstance();

06

07	if ( connectMode == 0 )

08

{

09	ret = conn.openConnection ( mContext, “cmwap”, "cmwap”, "cmwap” );

10

}

11

else

12

{

13	ret = conn.openConnection(mContext, “cmnet”, "", "");

14

}

15

}

13、PreferenceActivity 用法 

1	public class Setting extends PreferenceActivity

2

{

3	public void onCreate ( Bundle savedInstanceState )

4

{

5	super.onCreate ( savedInstanceState );

6	addPreferencesFromResource ( R.xml.settings );

7

}

8

}

Setting.xml: 

1	Android:key=”seting2″

2

3	android:title=”@string/seting2″

4	android:summary=”@string/seting2″/>

5	android:key=”seting1″

6	android:title=”@string/seting1″

7	android:summaryOff=”@string/seting1summaryOff”

8	android:summaryOn=”@stringseting1summaryOff”/>

14、通过HttpClient从指定server获取数据

01	DefaultHttpClient httpClient = new DefaultHttpClient();

02

03	HttpGet method = new HttpGet(“/templets/default/index.html”);

04	HttpResponse resp;

05	Reader reader = null;

06

07

try {

08	// AllClientPNames.TIMEOUT

09	HttpParams params = new BasicHttpParams();

10	params.setIntParameter(AllClientPNames.CONNECTION_TIMEOUT, 10000);

11

12	httpClient.setParams(params);

13	resp = httpClient.execute(method);

14	int status = resp.getStatusLine().getStatusCode();

15

16	if (status != HttpStatus.SC_OK)

17

{

18	return false;

19

}

20

21	// HttpStatus.SC_OK;

22	return true;

23

24

}

25	catch (ClientProtocolException e)

26

{

27	// TODO Auto-generated catch block

28	e.printStackTrace();

29

}

30	catch (IOException e)

31

{

32	// TODO Auto-generated catch block

33	e.printStackTrace();

34

}

35

finally

36

{

37	if (reader != null)

38

try

39

{

40	reader.close();

41

}

42	catch (IOException e)

43

{

44	// TODO Auto-generated catch block

45	e.printStackTrace();

46

}

47

}