How To Add More component dynamically React Native

问题

I want to add more components after clicking on the button. Can you share code or an idea so that I can implement? As the image shows, every time when user click on the add button, one row / component will be added.

回答1:

It's where state shining of,

for example:

constructor(props) {
   super(props);

   this._handleAddButton = this._handleAddButton.bind(this);

   this.state = {    /* initial your state. without any added component */
      data: []
   }
}

_handleAddButton() {
    let newly_added_data = { title: 'new title', content: 'new content goes here' };

    this.setState({
        data: [...this.state.data, newly_added_data]
    });
}

render() {
    let added_buttons_goes_here = this.state.data.map( (data, index) => {
        return (
            <MyComponent key={index} pass_in_data={data} />
        )
    });

    return (
        <View>
            <Button title="Add more" onPress={this._handleAddButton} />
            {added_buttons_goes_here}
        </View>
    );
}

So every time you click the button,

1. _handleAddButton get called
2. a new data is added, update with setState()
3. render() get triggered.
4. more <MyComponent> added into View and show

================

2017/8/3 edited:

if you want to further delete <MyComponent>, the prop key should be taken care of. The key act as change detector for react framework, an auto-increment key would suit your case. example:

_handleAddButton() {
    let newly_added_data = {
        /* psedo code to simulate key auto increment */
        key: this.state.data[this.state.data.length-1].key+1,
        title: 'new title',
        content: 'new content goes here'
    };

    this.setState({
        data: [...this.state.data, newly_added_data]
    });
}

_handleRemoveButton(key) {
    let result = this.state.data.filter( (data) => data.key !== key );

    this.setState({
        data: result,
    });
}

render() {
    let added_buttons_goes_here = this.state.data.map( (data, index) => {
        return (
            <MyComponent key={data.key} pass_in_data={data}>
                /// psedo code of pass-in remove button as a children
                <Button title="Remove" onPress={ () => this._handleRemoveButton(data.key) } />
            </MyComponent>
        )
    });

    return (
        <View>
            <Button title="Add more" onPress={this._handleAddButton} />
            {added_buttons_goes_here}
        </View>
    );
}

来源：https://stackoverflow.com/questions/45477583/how-to-add-more-component-dynamically-react-native