UIAlertView中的UITextView無法在iOS 4.x中工作

Question

在我的醫療應用程序中，我有一項新功能，允許用戶將PDF和其他資源下載到Documents文件夾以供離線查看。該應用程序支持iOS 4.1+和iOS 5.用戶在警報視圖中輸入下載文件的名稱。對於iOS 5，將文本字段放入警報現在很容易。對於類似的外觀和感覺在iOS的4.x中，該代碼通常會正常工作：

 alertNameEntryOld = [[UIAlertView alloc] init]; 
     [alertNameEntryOld setDelegate:self]; 
     [alertNameEntryOld setTitle:@"Enter new file name:"]; 
     [alertNameEntryOld setMessage:@" "]; 
     [alertNameEntryOld addButtonWithTitle:@"Cancel"]; 
     [alertNameEntryOld addButtonWithTitle:@"Continue"]; 

     //Check current device orientation. 
     UIDeviceOrientation interfaceOrientation = [[UIDevice currentDevice] orientation]; 

     //Place text field position appropriate to device position. 
     if (interfaceOrientation == UIInterfaceOrientationPortrait) 
      alertTextFieldOld = [[UITextField alloc] initWithFrame:CGRectMake(20.0, 45.0, 245.0, 25.0)]; 
     if (interfaceOrientation == UIInterfaceOrientationPortraitUpsideDown) 
      alertTextFieldOld = [[UITextField alloc] initWithFrame:CGRectMake(20.0, 45.0, 245.0, 25.0)]; 
     if (interfaceOrientation == UIInterfaceOrientationLandscapeLeft) 
      alertTextFieldOld = [[UITextField alloc] initWithFrame:CGRectMake(20.0, 30.0, 245.0, 25.0)]; 
     if (interfaceOrientation == UIInterfaceOrientationLandscapeRight) 
      alertTextFieldOld = [[UITextField alloc] initWithFrame:CGRectMake(20.0, 30.0, 245.0, 25.0)]; 

     [alertTextFieldOld setBackgroundColor:[UIColor whiteColor]]; 

     //Auto-capitalize first letter with shift key enabled. 
     [alertTextFieldOld setAutocapitalizationType:UITextAutocapitalizationTypeSentences]; 

     [alertNameEntryOld addSubview:alertTextFieldOld]; 
     [alertNameEntryOld show]; 
     [alertTextFieldOld release]; 

我無奈從這個代碼可以工作得很好了iOS 4.1的，4.2的事實推導和4.3的iPhone，以及如iPad上的iOS 4.1。但是，如果使用iOS 4.2或4.3在iPad中運行它，則相同的代碼會創建一個警告視圖，並且只會丟失文本字段。儘管我的應用程序適用於iPhone，但我當然不希望iPad用戶運行它來遇到此錯誤。看起來iOS軟件可能存在一個錯誤。任何想法修復或替代將非常感激。提前致謝。

Answer 1

嘗試這樣的：

UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Enter new file name:" message:@" " delegate:self cancelButtonTitle:@"Continue" otherButtonTitles:@"Cancel", nil]; 
UITextView *mTextView = [[UITextView alloc] init]; 
[mTextView setFrame:CGRectMake(20.0, 30.0, 245.0, 25.0)]; 
[alert addSubview:mTextView]; 
[mTextView release]; 
[alert show]; 
[alert release];