Android开发教程：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); 
 
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Cookie 
 
CookieSyncManager.createInstance(getApplicationContext()); 
        CookieManager.getInstance().removeAllCookie();