react-native/ReactAndroid/src/androidTest/js/LayoutEventsTestApp.js

/**
 * Copyright (c) 2013-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @providesModule LayoutEventsTestApp
 */

'use strict';

var React = require('React');
var View = require('View');

var RecordingModule = require('NativeModules').Recording;

const LAYOUT_SPECS = [
 [10, 10, 100, 100],
 [10, 10, 50, 50],
 [0, 0, 50, 50],
 [0, 0, 50, 50],
];

class LayoutEventsTestApp extends React.Component {

  constructor() {
    super();
    this.state = {
      specNumber: 0,
    };
    this.numParentLayouts = 0;
  }

  handleOnLayout = (e) => {
    var layout = e.nativeEvent.layout;
    RecordingModule.record(layout.x + ',' + layout.y + '-' + layout.width + 'x' + layout.height);

    if (this.state.specNumber >= LAYOUT_SPECS.length) {
      // This will cause the test to fail
      RecordingModule.record('Got an extraneous layout call');
    } else {
      this.setState({
        specNumber: this.state.specNumber + 1,
      });
    }
  };

  handleParentOnLayout = (e) => {
    if (this.numParentLayouts > 0) {
      // This will cause the test to fail - the parent's layout doesn't change
      // so we should only get the event once.
      RecordingModule.record('Got an extraneous layout call on the parent');
    }
    this.numParentLayouts++;
  };

  render() {
    const layout = LAYOUT_SPECS[this.state.specNumber];
    return (
      <View
          onLayout={this.handleParentOnLayout}
          testID="parent"
          style={{left: 0, top: 0, width: 500, height: 500}}>
        <View
            onLayout={this.handleOnLayout}
            testID="container"
            style={{left: layout[0], top: layout[1], width: layout[2], height: layout[3]}}/>
      </View>
    );
  }
}

module.exports = LayoutEventsTestApp;