Question

有没有更好的方法在Xcode for iPhone应用程序中执行以下操作？

我有一个主导航UIViewController屏幕，上面有4个按钮。

单击按钮1会显示一个子导航UIViewController，上面有4个按钮。单击按钮2显示相同的子导航UIViewController，但上面有5个按钮。单击按钮3显示相同的子导航UIViewController，但上面有4个按钮。单击按钮4显示相同的子导航UIViewController，但上面有6个按钮。

为了解决这个问题，我为主导航中的每个按钮分配了标签。单击一个按钮时，我会获取此标记号并将其传递给子导航UIViewController。

然后在子导航UIViewController中，根据这个值，我根据需要手动绘制/创建子导航按钮。

以下是我在子导航UIViewController中处理这个问题的方法。我检查从主导航UIViewController传递的值，并相应地绘制按钮数。我还为每个按钮设置了自定义背景图像。对于每个按钮单击我有自己的选择器方法。请注意，子导航中的某些按钮将转到UIViewController，而某些按钮将转到TableViewController。此外，每个子导航按钮都必须在其目标视图中显示自己的“内容”。

有更好，更优雅的方式处理这个吗？它似乎与我的代码重复很多。下面的例子简洁起见。

//  SubNavViewController.m
//  SegueTest
#import "SubNavViewController.h"
#import "GettingHereViewController.h"
#import "TableViewController.h"
#import "GettingHereContent.h"

@interface SubNavViewController ()
@end

@implementation SubNavViewController
@synthesize tagNumber;
@synthesize buttonNumber;
@synthesize buttonPushedTrackNumber;

@synthesize hotelButton;
@synthesize bAndBButton;
@synthesize caravanButton;
@synthesize selfCateringButton;
@synthesize apartmentsButton;
.
.
.
etc (19 in total)


- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
    } 
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    if (self.tagNumber == 1)
    {
        self.navigationItem.title = @"Getting Here";

        // By Air Button
        byAirButton = [UIButton buttonWithType:UIButtonTypeCustom];
        byAirButton.tag = 1;
        byAirButton.frame = CGRectMake(25, 140, 280.f, 40.f);
        UIImage *airButton = [UIImage imageNamed:@"gettingHereByAirButton.png"];
        [byAirButton setBackgroundImage:airButton forState:UIControlStateNormal];
        [self.view addSubview:byAirButton];
        [byAirButton addTarget:self action:@selector(byAirButtonClicked) forControlEvents:UIControlEventTouchUpInside];

        // By Rail Button
        byRailButton = [UIButton buttonWithType:UIButtonTypeCustom];
        byRailButton.tag = 2;
        byRailButton.frame = CGRectMake(25, 190, 280.f, 40.f);
        UIImage *railButton = [UIImage imageNamed:@"gettingHereByRailButton.png"];
        [byRailButton setBackgroundImage:railButton forState:UIControlStateNormal];
        [self.view addSubview:byRailButton];
        [byRailButton addTarget:self action:@selector(byRailButtonClicked) forControlEvents:UIControlEventTouchUpInside];

        .
        .
        . etc (2 more button)
    }
    else if (self.tagNumber == 2)
    {
        self.navigationItem.title = @"Where to Stay";

        // B&B Button
        bAndBButton = [UIButton buttonWithType:UIButtonTypeCustom];
        bAndBButton.tag = 1;
        bAndBButton.frame = CGRectMake(25, 140, 280.f, 40.f);
        UIImage *bedAndBreakfast = [UIImage imageNamed:@"whereToStayBedAndBreakfastButton.png"];
        [bAndBButton setBackgroundImage:bedAndBreakfast forState:UIControlStateNormal];
        [self.view addSubview:bAndBButton];
        [bAndBButton addTarget:self action:@selector(bAndBButtonClicked) forControlEvents:UIControlEventTouchUpInside];
        .
        .
        . etc (do this for the rest of the buttons)  
}

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

- (void) byAirButtonClicked
{
    GettingHereContent *gettingHere = [GettingHereContent new];
    gettingHere = @"By Air";
    NSLog(@"Content: %@", gettingHere);
    [self performSegueWithIdentifier:@"gettingHereSegue" sender:self];
}

- (void) bAndBButtonClicked
{
    GettingHereContent *gettingHere = [GettingHereContent new];
    gettingHere = @"Bed and Breakfast";
    NSLog(@"Content: %@", gettingHere);
    [self performSegueWithIdentifier:@"tableViewSegue" sender:self];
}

.
.
. (do this for all buttons - 19 in total)

- (void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
}
@end

Answer 1

首先，我建议按以下方式创建一个定义所有按钮的NS_ENUM：

typedef NS_ENUM(NSUInteger, ButtonTag)
{
    ButtonTagHotel,
    ButtonTagOther,
    ...
}

然后在viewDidLoad中：您可以创建一个包含所有按钮的数组，这些按钮是您当前状态所需的，如下所示：

NSMutableArray *buttonTags = [[NSMutableArray alloc] init];

if (self.tagNumber == 1 || self.tagNumber == 3)
    [buttonTags addObject: @(ButtonTagHotel)];

if (self.tagNumber == 5 || self.tagNumber == 8)
    [buttonTags addObject: @(ButtonTagOther)];

// etc...

当您构建所需的按钮标签时，您可以在一个循环中创建并添加它们：

uint cnt = 0;

for (NSNumber *tag in buttonTags)
{
    UIButton *btn = [UIButton buttonWithType:UIButtonTypeCustom];
    btn.tag = [tag unsignedIntValue];
    btn.frame = CGRectMake(25, 20 + (cnt * 50.f), 280.f, 40.f);
    UIImage *image = [UIImage imageNamed:@"genericButtonImage.png"];
    [btn setBackgroundImage:image forState:UIControlStateNormal];
    [self.view addSubview:btn];
    [btn addTarget:self action:@selector(buttonTouched:) forControlEvents:UIControlEventTouchUpInside];

    cnt++;
}

如果你必须为每个按钮设置不同的图像，那么你应该创建另一个数组，其中包含由ButtonTag枚举索引的所有图像名称......

现在你只需要实现 - （void）buttonTouched：（UIButton *）sender：

-(void)buttonTouched:(UIButton*)sender
{
    switch (sender.tag) {
        case ButtonTagHotel:
        {
            // do your stuff
        }
            break;
        ...
        default:
            break;
    }
}

在Xcode中创建按钮

1 个答案: