在android中每天的首次启动应用程序显示警报

1. Read a value (lastlaunchdatE) from shared preference.

2. check if current date = lastlaunchdate

3. If #2 is true,then ignore and proceed with usual flow

4. If #2 is false,then  

 4.a display the alert Box

  4.b save current date as lastlaunchdate in shared preference.

示例代码：

if (sharedPref.loadSharedPreference(getApplicationContext(),"LAST_LAUNCH_DATE").equals(new SimpleDateFormat("yyyy/MM/dd",Locale.US).format(new Date())))
{
    // Date matches. User has already Launched the app once today. So do nothing.
}
else
{
    // Display dialog text here......
    // Do all other actions for first time launch in the day...
    // Set the last Launched date to today.
    sharedPref.saveSharedPreference(getApplicationContext(),"LAST_LAUNCH_DATE",new SimpleDateFormat("yyyy/MM/dd",Locale.US).format(new Date()));
}