Android编程15个很有用的代码片段

Android代码

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);

7：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);

8: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();             }         }     };

9: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) {｝          }   

10:获得 手机ua public string getuseragent()     {            string user_agent = productproperties.get(productproperties.user_agent_key, null);             return user_agent;     }

11：清空手机上cookiecookiesyncmanager.createinstance(getapplicationcontext());         cookiemanager.getinstance().removeallcookie();

12：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”, “”, “”);             }     }

13：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”/>

14: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();                 }             }

15:显示toast toast.maketext(this._getapplicationcontext(), r.string._item, toast.length_short).show();