Question

在我的医疗应用程序中，我有一项新功能，允许用户将PDF和其他资源下载到Documents文件夹以供离线查看。该应用程序支持iOS 4.1+和iOS 5.用户在警报视图中输入下载文件的名称。对于iOS 5，现在可以轻松地在警报中放置文本字段。对于iOS 4.x中的类似外观，此代码通常运行良好：

        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];

我的沮丧源于这样一个事实：这个代码适用于iPhone上的iOS 4.1,4.2和4.3，以及iPad上的iOS 4.1。但是，如果在iOS 4.2或4.3中运行它，相同的代码会创建一个警告视图，文本字段就会丢失。虽然我的应用程序适用于iPhone，但我当然不希望运行它的iPad用户遇到此错误。似乎iOS软件中可能存在错误。任何修复或替代的想法将非常感激。提前谢谢。

Answer 1

试试这样：

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];

UIAlertview中的UITextView无法在iOS 4.x中运行

1 个答案: