判斷

/** 
  * 返回當前程序版本名 
  */ 
 public static String getAppVersionName(Context context) {  
    String versionName = "";  
    try {  
         // ---get the package info---  
         PackageManager pm = context.getPackageManager();  
        PackageInfo pi = pm.getPackageInfo(context.getPackageName(), 0);  
         versionName = pi.versionName;  
         if (versionName == null || versionName.length() <= 0) {  
            return "";  
        }  
    } catch (Exception e) {  
        }  
    return versionName;  
 } 
 
 /*
  * 判斷有沒有安裝某個應用程序
  * */ 
  public boolean checkApkExist(Context context, String packageName)
     {
             if (packageName == null || "".equals(packageName))
             {
                     return false;
             }
             try
             {
                     context.getPackageManager().getApplicationInfo(packageName,PackageManager.GET_UNINSTALLED_PACKAGES);
                     return true;
             }
             catch (NameNotFoundException e)
             {
                     return false;
             }
     }

//sdcard是否可讀寫 
public boolean IsCanUseSdCard() { 
    try { 
        return Environment.getExternalStorageState().equals( 
                Environment.MEDIA_MOUNTED); 
    } catch (Exception e) { 
        e.printStackTrace(); 
    } 
    return false; 
} 
//sim卡是否可讀 
public boolean isCanUseSim() { 
    try { 
        TelephonyManager mgr = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE); 
 
        return TelephonyManager.SIM_STATE_READY == mgr 
                .getSimState(); 
    } catch (Exception e) { 
        e.printStackTrace(); 
    } 
    return false; 
}