React Native TouchableOpacity not updating styles

Question

I have a strange issue with the TouchableOpacity component. I have a MainButton component which takes 2 props, item and disabled. Based on the the disabled prop I want my MainButton component to apply a different style. The problem is when the TouchableOpacity component re renders, it does not refresh the style. The prop disabled is correctly set on re render.

What makes this strange is that if i change it to a TouchableHeighlight it works as expected.

Does anyone know why? Is this a bug in TouchableOpacity?

import React, { Component } from 'react'
import UI from '../styles/ui'

import {
  Text,
  TouchableOpacity
} from 'react-native'

const ui = new UI()
const styles = ui.styles

class MainButton extends Component {
  constructor (props) {
    super(props)
    this.state = {
      disabled : props.disabled,
      item: props.item
    }
  }

  componentWillReceiveProps(props) {
    this.setState({disabled:props.disabled})
  }

  render() {
    var normalStyles = [styles.mainButton,styles.widthEighty]
    var disabledStyle = [styles.mainButton,styles.widthEighty,styles.lowOpacity]
    var correctStyles = this.state.disabled ? disabledStyle : normalStyles
    console.log(this.state.disabled,'this.state.disabled ? ');
    return (
      <TouchableOpacity disabled={this.state.disabled} style={correctStyles} accessibilityLabel={this.state.item.name} onPress={this.state.item.onPress.bind(this)}>
        <Text style={styles.mediumLabel}>{this.state.item.name}</Text>
      </TouchableOpacity>
    );
  }
}

export { MainButton as default }

Answer 1

I don't have enough context to understand exactly what you try to achieve here but try this:

  <TouchableOpacity disabled={this.state.disabled} style={this.state.disabled ? disabledStyle : normalStyles} accessibilityLabel={this.state.item.name} onPress={this.state.item.onPress.bind(this)}>
    <Text style={styles.mediumLabel}>{this.state.item.name}</Text>
  </TouchableOpacity>

There is also not enough context on what 'this.state.item.onPress' do, or why you use an item you pass in the props in order to change the props on the first place. It sounds like you can improve the way you implemented this, if you give me more context I might be able to help.

Answer 2

First, I don't think pass the disabled and item props to state. You can directly do it in this way and get rid of constructor as well as componentWillReceiveProps. componentWillReceiveProps lifecycle method will be deprecated soon, so they don't encourage its usage.

Also if possible, separate event handler from item props. It's not best way to do that

render () {
  const { disabled, item, onPress } = this.props;
  const { name } = item;
  ...
  return (
    ...
    <TouchableOpacity
      disabled={disabled}
      style={disabled ? disabledStyle : normalStyle}
      accessibilityLabel={name}
      onPress={onPress}
    >
      <Text style={styles.mediumLabel}>{name}</Text>
    </TouchableOpacity>
    ...
  ); 
}

Answer 3

The workaround I came up with is to use

setOpacityTo(value) in order to update the canvas.

I did this componentDidUpdate() as this lifecycle method get's called whenever your new style has been applied within your component. So I gave the <TouchableOpacity/> component a ref and updated it whenever it's style did change.

Example:

import React, { Component } from 'react'
import UI from '../styles/ui'

import {
  Text,
  TouchableOpacity
} from 'react-native'

const ui = new UI()
const styles = ui.styles

class MainButton extends Component {
  constructor (props) {
    super(props)
    this.state = {
      disabled : props.disabled,
      item: props.item
    }
  }

  componentWillReceiveProps(props) {
    this.setState({disabled:props.disabled})
  }

  componentDidUpdate() {
    this.refs['touchable'].setOpacityTo(1.0);
  }

  render() {
    var normalStyles = [styles.mainButton,styles.widthEighty]
    var disabledStyle = [styles.mainButton,styles.widthEighty,styles.lowOpacity]
    var correctStyles = this.state.disabled ? disabledStyle : normalStyles
    console.log(this.state.disabled,'this.state.disabled ? ');
    return (
      <TouchableOpacity ref={'touchable'} disabled={this.state.disabled} style={correctStyles} accessibilityLabel={this.state.item.name} onPress={this.state.item.onPress.bind(this)}>
        <Text style={styles.mediumLabel}>{this.state.item.name}</Text>
      </TouchableOpacity>
    );
  }
}

export { MainButton as default }

Answer 4

If you use opacity style (which using by TouchableOpacity), you should set this style for children of TouchableOpacity (ex a View) like this:

<TouchableOpacity
  disabled={disabled}
  accessibilityLabel={name}
  onPress={onPress}
>
  <View style={disabled ? disabledStyle : normalStyle}>
    <Text style={styles.mediumLabel}>{name}</Text>
  </View>
</TouchableOpacity>