使用 UIbutton 关闭弹出框

Question

当我尝试通过单击 UIButton 来关闭弹出框时，我无法弄清楚为什么它不能正常工作，而 UIButton 本身位于要关闭的弹出框上，我的项目崩溃了...

- (IBAction) cancelButton: (id) sender{
//[self dismissPopoverAnimated:YES];
}

以上是我的 UIButton 代码

Answer 1

不要从其自身中消除弹出框。制定一个协议，向其委托发送消息，然后将其关闭。例如，您的弹出视图控制器可能如下所示..

// MyPopoverViewController.h

@protocol MyPopoverDelegate <NSObject>
-(void)didClickCancelButton;
@end

@interface MyPopoverViewController : UIViewController {

}

@property (nonatomic, assign) id<MyPopoverDelegate> delegate; 

-(IBAction)cancelButton;

@end

// MyPopoverViewController.m
#import "MyPopoverViewController.h"

@implementation MyPopoverViewController

@synthesize delegate;

 // The designated initializer.  Override if you create the controller programmatically and want to perform customization that is not appropriate for viewDidLoad.

/*
// Implement viewDidLoad to do additional setup after loading the view, typically from a nib.
- (void)viewDidLoad {
    [super viewDidLoad];
}
*/

-(IBAction)cancelButton {
   [self.delegate didClickCancelButton];
}

#pragma mark -
#pragma mark Rotation support

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
    // Overriden to allow any orientation.
    return YES;
}

#pragma mark -
#pragma mark Memory Management

- (void)didReceiveMemoryWarning {
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];

    // Release any cached data, images, etc. that aren't in use.
}


- (void)viewDidUnload {
    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
}


- (void)dealloc {   
    [super dealloc];
}


@end

然后你可以使用..

//  ClassImplementingPopoverController.h

#import <UIKit/UIKit.h>
#import "MyPopoverViewController.h"

@interface ClassImplementingPopoverController : UIViewController <UIPopoverControllerDelegate, MyPopoverDelegate> {

    UIPopoverController *myPopoverController;
}

@property (nonatomic, retain) UIPopoverController *myPopoverController;

@end

//  ClassImplementingPopoverController.m

#import "ClassImplementingPopoverController.h"
#import "MyPopoverViewController.h"


@implementation ClassImplementingPopoverController

@synthesize myPopoverController;

#pragma mark -
#pragma mark View lifecycle


- (void)viewDidLoad {
    [super viewDidLoad];
}

 // Override to allow orientations other than the default portrait orientation.
 - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
 // Return YES for supported orientations.
     return YES;
 }

#pragma mark -
#pragma mark MyPopover delegate

-(void)didClickCancelButton {
    if ([myPopoverController isPopoverVisible]) {
       [myPopoverController dismissPopoverAnimated:YES];
       [myPopoverController release];
    }
 }

#pragma mark -
#pragma mark UIPopoverController delegate

-(void)popoverControllerDidDismissPopover:(UIPopoverController *)popoverController {
    if (popoverController == myPopoverController) {
        [myPopoverController release];
    }
}

/* Use something like this to create your popover, just make sure you set the delegate to self so you can receive the messages 

        NSLog(@"Displaying Popover!");
        MyPopoverViewController *detailViewController = [[MyPopoverViewController alloc] initWithNibName:@"MyPopoverViewController" bundle:nil];
        [detailViewController setDelegate:self];
        // Pass the selected object to the new view controller.     
        myPopoverController = [[UIPopoverController alloc] initWithContentViewController:detailViewController];
        [detailViewController release];
        myPopoverController.popoverContentSize = CGSizeMake(500.0, 150.0);
        [myPopoverController setDelegate:self];
*/

#pragma mark -
#pragma mark Memory management

- (void)didReceiveMemoryWarning {
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];

    // Relinquish ownership any cached data, images, etc. that aren't in use.
}

- (void)viewDidUnload {
    // Relinquish ownership of anything that can be recreated in viewDidLoad or on demand.
    // For example: self.myOutlet = nil;
    self.myPopoverController = nil;
}


- (void)dealloc {
    [myPopoverController release];
    [super dealloc];
}

@end

Answer 2

您可以使用 KVC 访问“popoverController”，如

[self valueForKey:@"popoverController"]

但如果 AppStore 检测到您的代码正在使用他们的“私有 API”，它可能会被拒绝。

Answer 3

dismissPopoverAnimated 是 PopoverController 本身的属性，而不是您的自定义 VC。您在“self”上展示了一个 IBAction，这表明您在自己的班级中。 （如果不正确，请发布更多周边代码。）

VC 不能直接到达其封闭的弹出框；您只需要在创建它的 VC 中保留对它的引用，这样您就可以从那里关闭它。

您可以从内部关闭 Popover，这不会崩溃。