RxSwift MVVM 实现查询

Posted 2023-03-10

【中文标题】RxSwift MVVM 实现查询

【英文标题】：RxSwift MVVM implemention inquire

【发布时间】：2018-08-01 01:25:43

【问题描述】：

我有两个UITextField 和一个UITableView 在一个UIViewController 中。这个UIViewController 的 ViewModel 公开了一个 Observable 作为表视图数据源。两个UITextField 从用户那里获取参数并刷新表视图Observable。 UITextField 使用 UIPickerView 作为 InputView，而 UIPickerViews 使用自定义类作为适配器。

在 UIViewController 中：

//bind the adapter to the UIPickerView
self.viewModel.dateList.bind(to: self.datePickerView.rx.items(adapter: self.viewModel.pickerViewAdapter)).disposed(by: rx.disposeBag)

在 ViewModel 中：

let dateList = Observable.just([[Int](0...1), [Int](1...12)])

final class PickerViewViewAdapter
    : NSObject
    , UIPickerViewDataSource
    , UIPickerViewDelegate
    , RxPickerViewDataSourceType
, SectionedViewDataSourceType 
    typealias Element = [[Int]]
    private var items: [[Int]] = []

    var activeTextField:UITextField!

    func model(at indexPath: IndexPath) throws -> Any 
        return items[indexPath.section][indexPath.row]
    

    func numberOfComponents(in pickerView: UIPickerView) -> Int 
        return items.count
    

    func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int 
        return items[component].count
    

    func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView 
        let label = UILabel()


        if component == 0
            label.text = "\(2018 - items[component][row])"
        else
            label.text = "\(items[component][row])"
        

        label.font = UIFont.preferredFont(forTextStyle: .title1)
        label.textAlignment = .center
        return label
    

    func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int)
///
/// Need to update the UITextField.text in a specific form
///
        

    func pickerView(_ pickerView: UIPickerView, observedEvent: Event<Element>) 
        Binder(self)  (adapter, items) in
            adapter.items = items
            pickerView.reloadAllComponents()
            .on(observedEvent)
    

用户从UIPickerView中选择后，我需要以特定形式更新UITextField.text，然后将这些文本用作API的参数。

我应该如何在 MVVM 中以 Reactive 方式执行此操作？

【参考方案1】：

我不确定您的代码中发生了什么，但也许这会有所帮助：

let items = Observable.just(Calendar.current.monthSymbols)
let pickerView = UIPickerView()

textField.inputView = pickerView

// this pipe displays the items in the picker view
items
    .bind(to: pickerView.rx.itemTitles)  $1 
    .disposed(by: bag)

// this pipe displays the picked item in the text field
Observable.combineLatest(items, pickerView.rx.itemSelected)  $0[$1.row] 
    .bind(to: textField.rx.text)
    .disposed(by: bag)