1

我的textfield表格中有一张。键入时textfield，我希望弹出框出现在pickerView里面。我以前用过popOverController，但在这种情况下，我不知道如何放置 apickerView并将其设置为表单视图控制器的委托和数据源，因为实际上弹出框需要一个独立的视图控制器。

我尝试了以下（该应用程序是通用的），弹出窗口没有出现：

- (IBAction)gradeTextfieldPressed:(UITextField *)sender
{

    if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPad) {

        [self.nameTextField resignFirstResponder];
        UIViewController *pickerController = [[UIViewController alloc] init];
        UIPickerView *pickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(self.gradeTextField.center.x, self.gradeTextField.center.y, 320, 320)];
        pickerView.delegate = self;
        pickerView.dataSource = self;
        [pickerController.view addSubview:pickerView];
        UIPopoverController *pickerPopover = [[UIPopoverController alloc] initWithContentViewController:pickerController];
        [pickerPopover presentPopoverFromRect:CGRectMake(self.gradeTextField.center.x, self.gradeTextField.center.y, 320, 320) inView:self.view permittedArrowDirections:UIPopoverArrowDirectionUp animated:YES];
        [self.gradeTextField setInputView:pickerView];
        if ([self.gradeTextField.text isEqualToString:@""]) {
            [self pickerView:pickerView didSelectRow:0 inComponent:0];
        }

    } else if([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone){
        [self.picker setHidden:NO];
        //[self pickerView:self.picker didSelectRow:0 inComponent:0];
        if ([self.gradeTextField.text isEqualToString:@""]) {
            [self pickerView:self.picker didSelectRow:0 inComponent:0];
        }
        [self.gradeTextField setInputView:self.picker];
        [self.nameTextField resignFirstResponder];
        [self.creditstextField resignFirstResponder];
        [self.chaptersTextField resignFirstResponder];
    }    
}
4

1 回答 1

0

我发现的一种方法很简单 创建一个只包含 PickerView 的新控制器（在本例中使用 .xib 完成），并有一个简单的委托协议让您的表单控制器知道何时选择了某些内容。

@protocol MyPickerDelegate <NSObject>
- (void)valuePicked:(NSString*)value
@end

@interface MyPickerController : UIViewController <UIPickerViewDelegate, UIPickerViewDataSource>
{
    __weak IBOutlet UIPickerView *_pickerView;
}
@property (nonatomic, weak) id<MyPickerDelegate> delegate;

然后，您可以在此控制器中实现数据源和委托方法。以下是物品被挑选时的代码：

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
    [_delegate valuePicked:[_myStrings objectAtIndex:row]];
}

最后，在调用类（您的表单控制器）中：

- (void)displayPickerFromRect:(CGRect)rect inView:(UIView*)view
{
    if (!_pickerController)
        _pickerController = [[MyPickerController alloc] initWithNibName:nil bundle:nil];

    if (_pickerController)
    {
        _speedPickerController.delegate = self;

        if (!_pickerPopover)
        {
            _pickerPopover = [[UIPopoverController alloc] initWithContentViewController:_pickerController];
            _pickerPopover.popoverContentSize = _pickerController.view.frame.size;
            _pickerPopover.delegate = self;
        }

        [_pickerPopover presentPopoverFromRect:rect inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
    }
}

- (void)popoverControllerDidDismissPopover:(UIPopoverController *)popoverController
{
    if (_pickerController)
    {
        _pickerController = nil;
        _pickerPopover = nil;
    }
}

- (void)valuePicked:(NSString*)value
{
   // do something with the picked value
   // dismiss the popover if you want it to go away as soon as a value is picked
}
于 2013-04-07T20:57:45.173 回答