Android很有用的程式碼片段

1：查看是否有儲存卡插入

String status=Environment.getExternalStorageState();if(status.equals(Enviroment.MEDIA_MOUNTED)){   說明有SD卡插入}

2：讓某個Activity透明

OnCreate中不設Layout this.setTheme(R.style.Theme_Transparent);
以下是Theme_Transparent的定義（注意transparent_bg是一副透明的圖片）

3：在螢幕元素中設定控制代碼

使用Activity.findViewById來取得螢幕上的元素的控制代碼. 使用該控制代碼您可以設定或擷取任何該對象外露的值.

TextView msgTextView = (TextView)findViewById(R.id.msg);   msgTextView.setText(R.string.push_me); 

4：傳送簡訊

          

 String body=”this is mms demo”;           Intent mmsintent = new Intent(Intent.ACTION_SENDTO, Uri.fromParts(”smsto”, number, null));           mmsintent.putExtra(Messaging.KEY_ACTION_SENDTO_MESSAGE_BODY, body);           mmsintent.putExtra(Messaging.KEY_ACTION_SENDTO_COMPOSE_MODE, true);           mmsintent.putExtra(Messaging.KEY_ACTION_SENDTO_EXIT_ON_SENT, true);            startActivity(mmsintent);

5：發送多媒體訊息

           

StringBuilder sb = new StringBuilder();            sb.append(”file://”);            sb.append(fd.getAbsoluteFile());            Intent intent = new Intent(Intent.ACTION_SENDTO, Uri.fromParts(”mmsto”, number, null));            // Below extra datas are all optional.            intent.putExtra(Messaging.KEY_ACTION_SENDTO_MESSAGE_SUBJECT, subject);            intent.putExtra(Messaging.KEY_ACTION_SENDTO_MESSAGE_BODY, body);            intent.putExtra(Messaging.KEY_ACTION_SENDTO_CONTENT_URI, sb.toString());            intent.putExtra(Messaging.KEY_ACTION_SENDTO_COMPOSE_MODE, composeMode);            intent.putExtra(Messaging.KEY_ACTION_SENDTO_EXIT_ON_SENT, exitOnSent);            startActivity(intent)

6：發送Mail

         

mime = “img/jpg”;            shareIntent.setDataAndType(Uri.fromFile(fd), mime);            shareIntent.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(fd));            shareIntent.putExtra(Intent.EXTRA_SUBJECT, subject);            shareIntent.putExtra(Intent.EXTRA_TEXT, body);

7：註冊一個BroadcastReceiver

registerReceiver(mMasterResetReciever, new IntentFilter(”oms.action.MASTERRESET”));private BroadcastReceiver mMasterResetReciever = new BroadcastReceiver() {        public void onReceive(Context context, Intent intent){            String action = intent.getAction();            if(”oms.action.MASTERRESET”.equals(action)){                RecoverDefaultConfig();            }        }    }

8：定義ContentObserver，監聽某個資料表

private ContentObserver mDownloadsObserver = new DownloadsChangeObserver(Downloads.CONTENT_URI);private class DownloadsChangeObserver extends ContentObserver {        public DownloadsChangeObserver(Uri uri) {            super(new Handler());        }        @Override        public void onChange(boolean selfChange) {｝          }

 
9：獲得 手機UA

public String getUserAgent()    {           String user_agent = ProductProperties.get(ProductProperties.USER_AGENT_KEY, null);            return user_agent;    }

10：清空手機上Cookie

CookieSyncManager.createInstance(getApplicationContext());        CookieManager.getInstance().removeAllCookie();

11：建立GPRS串連

 //Dial the GPRS link.    private boolean openDataConnection() {        // Set up data connection.        DataConnection conn = DataConnection.getInstance();                 if (connectMode == 0) {                ret = conn.openConnection(mContext, “cmwap”, “cmwap”, “cmwap”);            } else {                ret = conn.openConnection(mContext, “cmnet”, “”, “”);            }    }

12：PreferenceActivity 用法

public class Setting extends PreferenceActivity｛    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        addPreferencesFromResource(R.xml.settings)；    }｝Setting.xml:            android:key=”seting2″            android:title=”@string/seting2″            android:summary=”@string/seting2″/>            android:key=”seting1″            android:title=”@string/seting1″            android:summaryOff=”@string/seting1summaryOff”            android:summaryOn=”@stringseting1summaryOff”/>

13：通過HttpClient從指定server擷取資料

            

DefaultHttpClient httpClient = new DefaultHttpClient();            HttpGet method = new HttpGet(“http://www.baidu.com/1.html”);            HttpResponse resp;            Reader reader = null;            try {                // AllClientPNames.TIMEOUT                HttpParams params = new BasicHttpParams();                params.setIntParameter(AllClientPNames.CONNECTION_TIMEOUT, 10000);                httpClient.setParams(params);                resp = httpClient.execute(method);                int status = resp.getStatusLine().getStatusCode();                if (status != HttpStatus.SC_OK) return false;                // HttpStatus.SC_OK;                return true;            } catch (ClientProtocolException e) {                // TODO Auto-generated catch block                e.printStackTrace();            } catch (IOException e) {                // TODO Auto-generated catch block                e.printStackTrace();            } finally {                if (reader != null) try {                    reader.close();                } catch (IOException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                }            }