Xcode。西布。为文本元素设置默认字体
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【中文标题】Xcode。西布。为文本元素设置默认字体【英文标题】:Xcode. Xib. Set a default font for text elements 【发布时间】:2016-10-11 09:05:31 【问题描述】:当我创建它们时,如何为 xib 中的 UILabel、UITextView、UITextField 等文本元素设置默认字体?现在是系统17.0。
【问题讨论】:
【参考方案1】:无法直接在 Interface Builder 中执行此操作...但有一种方法可以通过涉及一些代码来完成此操作。
您需要递归查看子视图(因为子视图本身可以有更多的子视图)并在遇到它们时添加文本元素。
这是我的工作,在 Swift 3.0.2 中经过验证:
/// Recursively checks for UILabels, UITextFields, and UITextViews in a parent UIView and its subviews.
/// - parameter view: The UIView which may contain text elements for further, unified configuration.
/// - returns: A dictionary with UILabels, UITextFields, and UITextViews in their own arrays.
func textElementsInView(_ view: UIView) -> [String : Array<UIView>]
// Get the view's subviews.
let subviews = view.subviews
// Set up empty arrays for labels, text fields, and text views.
var labels : [UILabel] = []
var textFields : [UITextField] = []
var textViews : [UITextView] = []
// Check through the subviews in the given view.
for subview in subviews
if subview.isKind(of: UILabel.classForCoder())
// The subview is a label. Add it to the labels array.
labels.append(subview as! UILabel)
else if subview.isKind(of: UITextField.classForCoder())
// The subview is a text field. Add it to the textFields array.
textFields.append(subview as! UITextField)
else if subview.isKind(of: UITextView.classForCoder())
// The subview is a text view. Add it to the textViews array.
textViews.append(subview as! UITextView)
else
// The subview isn't itself a text element...but it could have some in it!
// Let's check it using this very function.
let elements = textElementsInView(subview)
// Add the labels...
let subviewLabels = elements["labels"] as! [UILabel]
labels.append(contentsOf: subviewLabels)
// ...and the text fields...
let subviewTextFields = elements["textFields"] as! [UITextField]
textFields.append(contentsOf: subviewTextFields)
// ...and the text views, to their respective arrays.
let subviewTextViews = elements["textViews"] as! [UITextView]
textViews.append(contentsOf: subviewTextViews)
// Once we're done with all that, set up our elements dictionary and return it.
let elements : [String : Array<UIView>] = ["labels" : labels, "textFields" : textFields, "textViews" : textViews]
return elements
在 Swift 中普遍应用样式的示例:
// Get the text elements in the given view.
let textElements = textElementsInView(view)
// Get the labels from the textElements dictionary.
let labels = textElements["labels"] as! [UILabel]
// Apply styles to any label in the labels array, all together.
for label in labels
label.font = UIFont.systemFont(ofSize: 24, weight: UIFontWeightBlack)
label.textColor = UIColor.black
...以及Objective-C中的方法:
- (NSDictionary*)textElementsInView: (UIView*)view
// First, set up mutable arrays for our text element types.
NSMutableArray *labels = [NSMutableArray new];
NSMutableArray *textFields = [NSMutableArray new];
NSMutableArray *textViews = [NSMutableArray new];
// And get an array with our subviews.
NSArray *subviews = [view subviews];
// Loop through the subviews in the subviews NSArray
for(UIView* subview in subviews)
if ([subview classForCoder] == [UILabel class])
// If the subview is a UILabel, add it to the labels array.
[labels addObject:subview];
else if ([subview classForCoder] == [UITextField class])
// If the subview is a UITextField, add it to the textFields array.
[textFields addObject:subview];
else if ([subview classForCoder] == [UITextView class])
// If the subview is a UITextView, add it to the labels array.
[textViews addObject:subview];
else
// Try running through this function for the view if none of the above matched.
NSDictionary *subviewTextElements = [self textElementsInView:subview];
// Get any labels in the subview and add them to the labels array.
NSArray *subviewLabels = [subviewTextElements objectForKey:@"labels"];
[labels addObjectsFromArray:subviewLabels];
// Do the same for UITextFields...
NSArray *subviewTextFields = [subviewTextElements objectForKey:@"textFields"];
[labels addObjectsFromArray:subviewTextFields];
// ...and UITextViews.
NSArray *subviewTextViews = [subviewTextElements objectForKey:@"textViews"];
[labels addObjectsFromArray:subviewTextViews];
// After all that's done, create a dictionary and return it.
NSDictionary *textElements = @
@"labels" : labels,
@"textFields" : textFields,
@"textViews": textViews
;
return textElements;
这当然不是很漂亮,但这是我能想到的完成工作的唯一方法。
【讨论】:
为objective-C写一个变种,赏金是你的:) @NikKov 使用 Obj-C 方法编辑。【参考方案2】:还有另一种可能的解决方案,但它比上述更“自动化”的解决方案需要更多的体力劳动。
即继承UILabel、UITextField等,并在init
中为该类设置默认字体,然后在Interface Builder中选择它们各自的对象并根据需要设置子类。
鉴于这不是我对这种情况的首选解决方案,我不会详细介绍我为其他答案所做的详细说明。但是,如果您对这个解决方案感到好奇,here's a helpful link 关于子类化 UILabel
从 Swift 1 天开始。我会说从那以后事情发生了一些变化,但是您自己应该很容易弄清楚。
重要提示:这些用于通用设置样式的解决方案都不会出现在 Interface Builder 中。这些是运行时设置,因此您只需确保在构建时正确设置了这些设置。
就个人而言,我建议仅手动设置它们而不是这些解决方案中的任何一个,除非您有一些需要这些选项中的任何一个的动态情况。
【讨论】:
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