2

我正在尝试实现一个自定义导航栏按钮项，当用户单击以调用一个函数时，我有一个选择器。如果我将栏项目设置为UIBarButtonItem它就可以正常工作，但我必须为按钮使用自定义图像，没有边框和适当的大小。

所以在 viewdidload 我打电话

- (void)viewDidLoad 
{
    [super viewDidLoad];
    //gear button on navigation Bar
    UIImage* imageback2 = [UIImage imageNamed:@"ICON - Gear-BarstyleItem@2x.png"];
    CGRect frameimgback2 = CGRectMake(0, 0, 40, 40);

    UIButton *backButton2 = [[UIButton alloc] initWithFrame:frameimgback2];
    [backButton2 setBackgroundImage:imageback2 forState:UIControlStateNormal];
    [backButton2 addTarget:self
                    action:@selector(setColorButtonTapped:)
          forControlEvents:UIControlEventTouchUpInside];

    UIBarButtonItem *btn2 = [[UIBarButtonItem alloc] initWithCustomView:backButton2];


    UIBarButtonItem *btn3 =[[UIBarButtonItem alloc] initWithImage:imageback2 style:UIBarButtonItemStylePlain target:self action:@selector(setColorButtonTapped:)];

    self.navigationItem.rightBarButtonItem = btn2;
}

#pragma mark Callbacks

- (IBAction)setColorButtonTapped:(id)sender{
    if (_colorPicker == nil) {
        self.colorPicker = [[ColorPickerController alloc] initWithStyle:UITableViewStylePlain];
        _colorPicker.delegate = self;
        self.colorPickerPopover = [[UIPopoverController alloc] initWithContentViewController:_colorPicker];
    }
    [self.colorPickerPopover presentPopoverFromBarButtonItem:sender permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
}

这给了我：

-[UIButton view]: unrecognized selector sent to instance 0x9466620
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIButton view]: unrecognized selector sent to instance 0x9466620'

如果我设置

 self.navigationItem.rightBarButtonItem = btn2;

到

 self.navigationItem.rightBarButtonItem = btn3;

它工作正常，但按钮有边框和背景颜色和较小的图像尺寸

那么为什么它给我错误，我怎样才能让这个按钮成为一个自定义按钮呢？

编辑：

当我添加一个 void 函数时

- (void)gearTapped{
    [self setColorButtonTapped:self];
}

并在按钮处更改选择器它不会给出任何错误，但它只会在屏幕中间显示弹出一行

[backButton2 addTarget:self
                    action:@selector(gearTapped)
          forControlEvents:UIControlEventTouchUpInside];

在此处输入图像描述

它通常应该像这样工作，但有一个自定义按钮 在此处输入图像描述

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3 回答 3

6

您将UIButton实例作为sender参数传递给您的操作。然后sender作为参数传递给期望UIBarButtonItem此处实例的方法：

[self.colorPickerPopover presentPopoverFromBarButtonItem:sender permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];

如果你打算sender在你的动作中使用这个参数，你应该对两个不同类别的对象进行单独的动作。像：

- (void)loadColorPicker
{
    if (_colorPicker == nil) {
        self.colorPicker = [[ColorPickerController alloc] initWithStyle:UITableViewStylePlain];
        _colorPicker.delegate = self;
        self.colorPickerPopover = [[UIPopoverController alloc] initWithContentViewController:_colorPicker];
    }
}
- (void)colorBarButtonItemTapped:(UIBarButtonItem *)sender
{
    [self loadColorPicker];
    [self.colorPickerPopover presentPopoverFromBarButtonItem:sender permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
}

- (void)colorButtonTapped:(UIButton *)sender
{
    [self loadColorPicker];
    [self.colorPickerPopover presentPopoverFromRect:sender.frame inView:self.view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
}

然后在哪里分配目标和操作：

[backButton2 addTarget:self
                action:@selector(colorButtonTapped:)
      forControlEvents:UIControlEventTouchUpInside];

UIBarButtonItem *btn3 =[[UIBarButtonItem alloc] initWithImage:imageback2 style:UIBarButtonItemStylePlain target:self action:@selector(colorBarButtonItemTapped:)];

希望这可以帮助！

于 2012-09-26T18:20:34.763 回答
0 
UIView* btnView = [[UIView alloc] initWithFrame: backButton2.bounds];
[btnView addSubview: backButton2];

UIBarButtonItem *btn2 = [[UIBarButtonItem alloc] initWithCustomView:btnView];

//in case you are not using arc
[btnView release];

干杯...

于 2012-09-26T16:41:05.483 回答
0

您的错误可能是因为您不应该初始化UIButtonusing alloc/initWithFrame而是使用其buttonWithType:设计的初始化程序（然后单独设置其框架）。

于 2012-09-26T16:43:25.327 回答