React-native: View: Style doesn't update with setState

[aniss]

When I try to change the View style by changing the state. it will not respond. Do you have any idea why?

var React = require('react-native');

var { View, Text} = React;

var TouchIt = React.createClass({

  getInitialState() {
    return {
      style: style
    }
  },

  shouldSetResponder() {
    return true;
  },

  shouldSetMoveResponder() {
    return true;
  },

  responderGrant() {
    console.log('finger in');
  },

  responderMove() {
    var style = this.state.style;
    style.backgroundColor = this.getRandomColor();
    this.setState({backgroundColor: backgroundColor});
  },

  responderRelease() {
    console.log('finger out');
  },

  getRandomColor() {
    var randomColor = '#'+Math.random().toString(16).substr(-6);
    return randomColor;
  },

  render() {

    return (
        <View style={this.state.style}
          onStartShouldSetResponder={this.shouldSetResponder}
          onMoveShouldSetResponder={this.shouldSetMoveResponder}
          onResponderGrant={this.responderGrant}
          onResponderMove={this.responderMove}
          onResponderRelease={this.responderRelease}
          >
          <Text>{this.style.backgroundColor}</Text>
        </View>
    );
  }

});

var style = {
  backgroundColor: 'rgb(11, 135, 91)',
  flex: 1
}

module.exports = TouchIt;

[ide]

Not sure if this will fix things but try changing the first line in responderMove to var style = {...this.state.style}; so that you create a new object and make it clear that the new View on the second render pass has a different style than the first one.

[PhilippKrone]

Not 100% sure as I have not tested it, but you seem to have two backgroundColors, one in your "var style" and the other in "this.state" and I think you are mixing them up. You should decide whether you want to have the backgroundColor saved here or there, and respectively set the correct value in your responderMove method.

[brentvatne]

Here you go!

var React = require('react-native');

var {
  AppRegistry,
  Image,
  ScrollView,
  StyleSheet,
  Text,
  View,
} = React;

var ExampleApp = React.createClass({

  getInitialState() {
    return {
      style: style
    }
  },

  shouldSetResponder() {
    return true;
  },

  shouldSetMoveResponder() {
    return true;
  },

  responderGrant() {
    console.log('finger in');
  },

  responderMove() {
    var backgroundColor = this.getRandomColor();
    this.setState({style: {backgroundColor}});
  },

  responderRelease() {
    console.log('finger out');
  },

  getRandomColor() {
    var randomColor = '#'+Math.random().toString(16).substr(-6);
    return randomColor;
  },

  render() {

    return (
        <View style={[{flex: 1}, this.state.style]}
          onStartShouldSetResponder={this.shouldSetResponder}
          onMoveShouldSetResponder={this.shouldSetMoveResponder}
          onResponderGrant={this.responderGrant}
          onResponderMove={this.responderMove}
          onResponderRelease={this.responderRelease}
          >
          <Text>{this.state.style.backgroundColor}</Text>
        </View>
    );
  }

});

var style = {
  backgroundColor: 'rgb(11, 135, 91)',
  flex: 1
}

Lots of issues with variables, check out my code above to see where you went wrong :) By the way, this kind of question is better suited for StackOverflow!