React-Native : measure a View

Question

I\'m trying to measure a view using a ref, but the width returned is 0 despite the fact that I see the view displayed on the screen (and it\'s far

Answer 1

You want to measure the progress bar onLayout.

var Time = React.createClass({
  getInitialState: function() {
    return({ progressMaxSize: 0 }); 
  },
  measureProgressBar: function() {
    this.progressBar.measure(this.setWidthProgressMaxSize);
  },
  setWidthProgressMaxSize: function(ox, oy, width, height, px, py) {
    this.setState({ progressMaxSize: width });
  },
  render: function() {
    return(
       { this.progressBar = c; } onLayout={this.measureProgressBar}>
        
          
        
      
    );
  }
});