3.Use one UIAlertView to pass the string parameter to display multiple way Alert Message//.

-(void)Show_Alert:(NSString*)strMessage

{

    UIAlertView *alertView = [[UIAlertView alloc]initWithTitle:nil message:strMessage delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];

    [alertView show];

}

// some method here

     if ([txtSchDate.text length]==0)

        {

            [self Show_Alert:@"Please select schedule date"];return;

        }

        if ([txtSchStartTime.text length]==0)

        {

            [self Show_Alert:@"Please select Start Time"];return;

        }

        if ([txtSchEndTime.text length]==0)

        {

            [self Show_Alert:@"Please select End Time"];return;

        }