Dojo 2如何实现输入的双向绑定？

Question

How to achieve 2 way data binding for input in dojo 2?

handleChange = (e) => {
  this.setState({ textValue: e.target.value });}
<Input name='title' defaultValue={this.state.textValue} placeholder='title...' onChange={this.handleChange} />

I know this is how we do in React but don't know how to achieve in dojo 2.

Answer 1

In fact React supports only one-way binding, and your example illustrates it well. You need to update state, to re-render react component. And as far as I understood from dojo2 docs and tutorials, there is almost same approach under the hood. Take a look here

Dojo 2 is built around unidirectional, top-down property propagation where it is the parent widget's job to pass properties down to its children. In fact, a child widget has no direct reference to a parent widget! When a property changes, widgets are re-rendered (using an efficient virtual DOM) to reflect the updated state.

And it may look like this:

private _addWorker() {
        this._workerData = this._workerData.concat(this._newWorker);
        this._newWorker = {};
        this.invalidate();
    }

You change data and call invalidate() to re-render widget.

Answer 2

This is the solution to achieve 2 way data binding in Dojo 2.

InputWidget:-

interface IInputProps {
   value: string;
   onChange(event: Event): void;
}
export class InputWidget extends WidgetBase<IInputProps> {
  private _onChange (event: Event) {
    event.stopPropagation();
    this.properties.onChange && this.properties.onChange((event.target as HTMLInputElement).value);
  }

  protected render(): DNode {
    const { value } = this.properties;
    return v('input', { 
        key: "input",
        type: "text",
        value
        onchange: this._onChange
    });
  }
}

InputWrapper widget:-

export class InputWrapper extends WidgetBase<IWrapperProps> {
  private inputValue: string = ''; 
  protected inputValueChanges(value: string) {
    this.inputValue = value;
    this.invalidate();
  }

  protected render(): DNode {
    <div>
        {w(InputWidget, {onchange: this.inputValueChanges, value: this.inputValue })}
        <span>Input Value:- {this.inputValue}</span>
    </div>

  }
}

This is the solution to achieve 2 way data binding in Dojo 2.

Hope this will be helpful! :(