ios - 用 initWithFrame 编写的类——我想从 Storyboard 实例化

Question

我想使用 UIExpandableTableView - https://github.com/OliverLetterer/UIExpandableTableView#readme。

我遇到了一个问题，因为它唯一的初始化程序是initWithFrame：

#pragma mark - Initialization

- (id)initWithFrame:(CGRect)frame style:(UITableViewStyle)style {
    if ((self = [super initWithFrame:frame style:style])) {
        self.maximumRowCountToStillUseAnimationWhileExpanding = NSIntegerMax;
        self.expandableSectionsDictionary = [NSMutableDictionary dictionary];
        self.showingSectionsDictionary = [NSMutableDictionary dictionary];
        self.downloadingSectionsDictionary = [NSMutableDictionary dictionary];
        self.animatingSectionsDictionary = [NSMutableDictionary dictionary];
    }
    return self;
}

我一直在尝试从 Storyboard 初始化 tableView 并意识到我看到的错误是因为它initWithFrame从未被调用并且NSMutableDictionaries没有被初始化。如何解决这个问题？

如果不容易解决，我可以以编程方式实例化并使用initWithFrame，但除了想使用 Storyboard 之外，我也很好奇解决方案会是什么。

---

编辑以下是这些属性及其 ivars 在 UIExpandableTableView 中的声明方式。这是在 .h 文件中：

@interface UIExpandableTableView : UITableView <UITableViewDelegate, UITableViewDataSource, NSCoding> {

@private id __UIExpandableTableView_weak _myDelegate; id __UIExpandableTableView_weak _myDataSource;

NSMutableDictionary *_expandableSectionsDictionary;     // will store BOOLs for each section that is expandable
NSMutableDictionary *_showingSectionsDictionary;        // will store BOOLs for the sections state (nil: not expanded, 1: expanded)
NSMutableDictionary *_downloadingSectionsDictionary;    // will store BOOLs for the sections state (nil: not downloading, YES: downloading)
NSMutableDictionary *_animatingSectionsDictionary;

NSInteger _maximumRowCountToStillUseAnimationWhileExpanding;

BOOL _onlyDisplayHeaderAndFooterViewIfTableViewIsNotEmpty;
UIView *_storedTableHeaderView;
UIView *_storedTableFooterView;

}

这是 UIExpandableTableView 的 .m 文件的顶部。吨

@interface UIExpandableTableView ()

@property (nonatomic, retain) NSMutableDictionary *expandableSectionsDictionary;
@property (nonatomic, retain) NSMutableDictionary *showingSectionsDictionary;
@property (nonatomic, retain) NSMutableDictionary *downloadingSectionsDictionary;
@property (nonatomic, retain) NSMutableDictionary *animatingSectionsDictionary;

@property (nonatomic, retain) UIView *storedTableHeaderView;
@property (nonatomic, retain) UIView *storedTableFooterView;

- (void)downloadDataInSection:(NSInteger)section;

- (void)_resetExpansionStates;

@end

Answer 1

您所要做的就是删除initWithFrame:并覆盖initWithCoder:。当界面构建器元素到达 init 以允许您设置字典时，将调用此方法。并且不要担心消除样式和框架参数，因为这两种情况都将在界面生成器中处理。

- (id)initWithCoder:(NSCoder *)aDecoder
{
    if (self = [super initWithCoder:aDecoder]) {
        NSLog(@"%s",__PRETTY_FUNCTION__); // Proof of call
        self.maximumRowCountToStillUseAnimationWhileExpanding = NSIntegerMax;
        self.expandableSectionsDictionary = [NSMutableDictionary dictionary];
        self.showingSectionsDictionary = [NSMutableDictionary dictionary];
        self.downloadingSectionsDictionary = [NSMutableDictionary dictionary];
        self.animatingSectionsDictionary = [NSMutableDictionary dictionary];
    }
    return self;
}

Answer 2

你可以从 UIExpandableTableView 子类化，然后做

- (id)initWithFrame:(CGRect)frame style:(UITableViewStyle)style {
    if (self = [super initWithFrame:frame style:style]) {
        [self configure];
    }
    return self;
}


-(id)initWithCoder:(NSCoder *)aCoder {
    if(self = [super initWithCoder:aCoder]){ 
        [self configure];
    }
   return self;
}


-(void) configure {
    self.maximumRowCountToStillUseAnimationWhileExpanding = NSIntegerMax;
    self.expandableSectionsDictionary = [NSMutableDictionary dictionary];
    self.showingSectionsDictionary = [NSMutableDictionary dictionary];
    self.downloadingSectionsDictionary = [NSMutableDictionary dictionary];
    self.animatingSectionsDictionary = [NSMutableDictionary dictionary];
}

Nibs 和 Storybord 实例化是通过initWithCoder:

在这种情况下，Subcalssing 允许您使用未打补丁的第三方代码。

Answer 3

我会做以下事情：

- (id)initWithFrame:(CGRect)frame style:(UITableViewStyle)style {
    if ((self = [super initWithFrame:frame style:style])) {
        [self setup];
    }
    return self;
}

- (void)awakeFromNib {
    [super awakeFromNib];
    [self setup];
}

- (void)setup {
    self.maximumRowCountToStillUseAnimationWhileExpanding = NSIntegerMax;
    self.expandableSectionsDictionary = [NSMutableDictionary dictionary];
    self.showingSectionsDictionary = [NSMutableDictionary dictionary];
    self.downloadingSectionsDictionary = [NSMutableDictionary dictionary];
    self.animatingSectionsDictionary = [NSMutableDictionary dictionary];
}

Answer 4

我认为这是最简单的解决方案……您不必担心视图控制器的初始化方式。

-(void)viewDidLoad
{
    [super viewDidLoad];
    self.maximumRowCountToStillUseAnimationWhileExpanding = NSIntegerMax;
    self.expandableSectionsDictionary = [NSMutableDictionary dictionary];
    self.showingSectionsDictionary = [NSMutableDictionary dictionary];
    self.downloadingSectionsDictionary = [NSMutableDictionary dictionary];
    self.animatingSectionsDictionary = [NSMutableDictionary dictionary];
}