Dynamic content with NSLocalizedString

FaqViewModel.swift

import Foundation

struct FaqCategory: Equatable {
	let id: Int
	let name: String
	let items: [FaqItem]
}
func ==(lhs: FaqCategory, rhs: FaqCategory) -> Bool {
	return lhs.id == rhs.id
}

struct FaqItem: Equatable {
	let id: Int
	let question: String
	let answer: String
}
func ==(lhs: FaqItem, rhs: FaqItem) -> Bool {
	return lhs.id == rhs.id
}

struct FaqCategoriesViewModel {
	
	var categories: [FaqCategory] = []
	
	init() {
		var catId = 1
		var catKey = String(format: "faq.c.%d.title", catId)
		
		while NSLocalizedString(catKey, comment: "") != catKey {
			var items: [FaqItem] = []
			var itemId = 1
			var questionKey = String(format: "faq.c.%d.q.%d.q", catId, itemId)
			var answerKey = String(format: "faq.c.%d.q.%d.a", catId, itemId)
			
			while NSLocalizedString(questionKey, comment: "") != questionKey
				&& NSLocalizedString(answerKey, comment: "") != answerKey {
					
				items.append(
					FaqItem(
						id: itemId,
						question: NSLocalizedString(questionKey, comment: ""),
						answer: NSLocalizedString(answerKey, comment: "")
					)
				)
				itemId += 1
				questionKey = String(format: "faq.c.%d.q.%d.q", catId, itemId)
				answerKey = String(format: "faq.c.%d.q.%d.a", catId, itemId)
			}
			
			categories.append(
				FaqCategory(
					id: catId,
					name: NSLocalizedString(catKey, comment: ""),
					items: items
				)
			)
			catId += 1
			catKey = String(format: "faq.c.%d.title", catId)
		}
	}
	
}

struct FaqCategoryViewModel {
	var category: FaqCategory
	init(category: FaqCategory) {
		self.category = category
	}
}

Localizable.strings

"faq.c.1.title" = "Category 1";
"faq.c.1.q.1.q" = "Question 1";
"faq.c.1.q.1.a" = "Answer 1";

"faq.c.2.title" = "Category 2";
"faq.c.2.q.1.q" = "Question 1";
"faq.c.2.q.1.a" = "Answer 1";
"faq.c.2.q.2.q" = "Question 2";
"faq.c.2.q.2.a" = "Answer 2";

func faqCategories() -> [FaqCategory] {
    var categories: [FaqCategory] = []
    
    var catIx = 1
    while let categoryTitle = category(catIx) {
        var questions: [FaqQuestion] = []
        
        var questionIx = 1
        while let question = question(questionIx, catIx: catIx), let answer = answer(questionIx, catIx: catIx) {
            let faqQuestion = FaqQuestion(question: question, answer: answer)
            questions.append(faqQuestion)
            questionIx += 1
        }
        
        let faqCategory = FaqCategory(title: categoryTitle, questions: questions)
        categories.append(faqCategory)
        
        catIx += 1
    }
    
    return categories
}

private func category(_ ix: Int) -> String? {
    return localizedStringOrNil(key: "faq.\(ix).title")
}

private func question(_ ix: Int, catIx: Int) -> String? {
    return localizedStringOrNil(key: "faq.\(catIx).\(ix).question")
}

private func answer(_ ix: Int, catIx: Int) -> String? {
    return localizedStringOrNil(key: "faq.\(catIx).\(ix).answer")
}

private func localizedStringOrNil(key: String) -> String? {
    let string = NSLocalizedString(key, comment: "")
    return string == key ? nil : string
}