我最近一直在问有关UIToolbars的问题,但现在我发现我需要在程序中添加项目,我看到其他人处理此事的方法,但当我尝试做同样的事情时,什么也没有出现。我需要帮助解决这个问题。以下是我在IB中的连接:
以下是相关代码:
头文件:
#import <UIKit/UIKit.h>
@interface ParkingRootViewController : UIViewController {
UINavigationController *navigationController;
UIToolbar *toolbar;
UIBarButtonItem *lastUpdateLabel;
}
@property(nonatomic, retain) IBOutlet UINavigationController *navigationController;
@property (nonatomic, retain) IBOutlet UIToolbar *toolbar;
@property (nonatomic, retain) IBOutlet UIBarButtonItem *lastUpdateLabel;
- (IBAction)selectHome:(id)sender;
@end
实现文件:
- (void)viewDidLoad {
[super viewDidLoad];
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 150.0f, 20.0f)];
label.text = @"last updated...";
label.textColor = [UIColor colorWithWhite:1.0 alpha:1.0];
label.backgroundColor = [UIColor clearColor];
label.textAlignment = UITextAlignmentCenter;
label.font = [UIFont boldSystemFontOfSize:13.0];
label.userInteractionEnabled = NO;
lastUpdateLabel = [[UIBarButtonItem alloc] initWithCustomView:label];
[label release];
[toolbar setItems:[NSArray arrayWithObject:lastUpdateLabel]];
[self.view addSubview:self.navigationController.view];
//[self.view addSubview:toolbar];
//[self.navigationController.view addSubview:toolbar];
[self.navigationController.view setFrame:self.view.frame];
}
非常感谢您的帮助!
编辑:
我已经删除了nib文件中可能导致工具栏出现/被修改的内容,并且我在viewDidLoad方法中更新了我的代码,如下所示:
self.navigationController.toolbarHidden = NO;
//creating label in tool bar
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 150.0f, 20.0f)];
label.text = @"last updated...";
label.textColor = [UIColor colorWithWhite:1.0 alpha:1.0];
label.backgroundColor = [UIColor clearColor];
label.textAlignment = UITextAlignmentCenter;
//label.highlightedTextColor = [UIColor colorWithWhite:0.5 alpha:1.0];
//label.highlighted = YES;
label.font = [UIFont systemFontOfSize:13.0];
label.userInteractionEnabled = NO;
UIBarButtonItem *lastUpdateLabel = [[UIBarButtonItem alloc] initWithCustomView:label];
//[lastUpdateLabel initWithCustomView:label];
//[label release];
//[toolbar setItems:[NSArray arrayWithObject:lastUpdateLabel]];
[self setToolbarItems:[NSArray arrayWithObject:lastUpdateLabel]];
我最终得到了一个空白的工具栏。我启动调试器,看到以下内容:
![enter image description here](https://istack.dev59.com/GqLdv.webp)
啊哈!lastUpdateLabel的视图的_text字段超出了范围!但是为什么?我该如何解决?
编辑2:
我已经能够使用以下代码添加标签和NSActivityIndicator:
@synthesize refreshDataButton;
//...
self.navigationController.toolbarHidden = NO;
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(20.0f, 0.0f, 80.0f, 40.0f)];
label.text = @"last updated...";
label.textColor = [UIColor colorWithWhite:1.0 alpha:1.0];
label.backgroundColor = [UIColor clearColor];
label.textAlignment = UITextAlignmentCenter;
label.font = [UIFont systemFontOfSize:13.0];
label.userInteractionEnabled = NO;
[self.toolbar addSubview:label];
// create activity indicator
// dist frm lft, dist frm top
CGRect frame = CGRectMake( 90.0, 11.0, 25.0, 25.0);
UIActivityIndicatorView *loading = [[UIActivityIndicatorView alloc] initWithFrame:frame];
loading.activityIndicatorViewStyle = UIActivityIndicatorViewStyleWhite;
[loading sizeToFit];
loading.autoresizingMask = (UIViewAutoresizingFlexibleLeftMargin |
UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleTopMargin |
UIViewAutoresizingFlexibleBottomMargin);
[loading startAnimating];
[self.toolbar addSubview:loading];
但是当我尝试添加一个UIBarButtonItem时,我没有成功(在工具栏中没有显示):
self.refreshDataButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:100 target:self action:@selector(refreshDataButtonTapped)];
[self setToolbarItems:[NSArray arrayWithObject:refreshDataButton]];
这是头文件:
#import <UIKit/UIKit.h>
//#import <CoreData/CoreData.h>
@interface ParkingRootViewController : UIViewController {
UINavigationController *navigationController;
UIToolbar *toolbar;
UIBarButtonItem *refreshDataButton;
//UIActivityIndicatorView *loading;
}
@property (nonatomic, retain) IBOutlet UINavigationController *navigationController;
@property (nonatomic, retain) IBOutlet UIToolbar *toolbar;
@property (nonatomic, retain) UIBarButtonItem *refreshDataButton;
//@property (nonatomic, retain) IBOutlet UIActivityIndicatorView *loading;
@property (nonatomic, readonly) NSString *applicationDocumentsDirectory;
-(IBAction)selectHome:(id)sender;
-(void)testCoreData;
-(void)refreshDataButtonTapped;
@end