Android很有用的代码片段

1：查看是否有存储卡插入

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

2：让某个Activity透明

OnCreate中不设Layout this.setTheme(R.style.Theme_Transparent);
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.

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

4：发送短信

          

 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：发送彩信

           

 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：发送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：注册一个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：定义ContentObserver，监听某个数据表

 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：获得 手机UA

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

10：清空手机上Cookie

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

11：建立GPRS连接

 //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：通过HttpClient从指定server获取数据

            

 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();
                 }
             }