UIPickerView在窗体页面viewController(iPad)内的弹出窗口中

时间:2013-04-07 18:32:41

标签: ios objective-c uipickerview uipopovercontroller

我的表单中有textfield。当输入textfield时,我希望弹出窗口中出现pickerView。我之前使用过popOverController,但在这种情况下,我不知道如何放置pickerView并将其委托和数据源设置为表单查看控制器,因为实际上popover需要一个独立的视图控制器。

我尝试了以下(应用程序是通用的),popover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];
    }    
}

1 个答案:

答案 0 :(得分:0)

这样做的一种方法,我发现简单创建一个只有PickerView的新控制器(在这种情况下用.xib完成),并有一个简单的委托协议,让你的表单控制器知道什么时候有什么拾取。

@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。这是选择项目时的代码:

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

最后,在调用类(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
}