@instructure/quiz-interactions/es/components/hotspot/common/Canvas/index.js

A React UI component Library for quiz interaction types.

import _classCallCheck from "@babel/runtime/helpers/esm/classCallCheck";
import _createClass from "@babel/runtime/helpers/esm/createClass";
import _possibleConstructorReturn from "@babel/runtime/helpers/esm/possibleConstructorReturn";
import _getPrototypeOf from "@babel/runtime/helpers/esm/getPrototypeOf";
import _inherits from "@babel/runtime/helpers/esm/inherits";
import _defineProperty from "@babel/runtime/helpers/esm/defineProperty";
var _dec, _class, _Canvas;
function ownKeys(object, enumerableOnly) { var keys = Object.keys(object); if (Object.getOwnPropertySymbols) { var symbols = Object.getOwnPropertySymbols(object); if (enumerableOnly) { symbols = symbols.filter(function (sym) { return Object.getOwnPropertyDescriptor(object, sym).enumerable; }); } keys.push.apply(keys, symbols); } return keys; }
function _objectSpread(target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i] != null ? arguments[i] : {}; if (i % 2) { ownKeys(Object(source), true).forEach(function (key) { _defineProperty(target, key, source[key]); }); } else if (Object.getOwnPropertyDescriptors) { Object.defineProperties(target, Object.getOwnPropertyDescriptors(source)); } else { ownKeys(Object(source)).forEach(function (key) { Object.defineProperty(target, key, Object.getOwnPropertyDescriptor(source, key)); }); } } return target; }
function _callSuper(_this, derived, args) {
  function isNativeReflectConstruct() {
    if (typeof Reflect === "undefined" || !Reflect.construct) return false;
    if (Reflect.construct.sham) return false;
    if (typeof Proxy === "function") return true;
    try {
      return !Boolean.prototype.valueOf.call(Reflect.construct(Boolean, [], function () {}));
    } catch (e) {
      return false;
    }
  }
  derived = _getPrototypeOf(derived);
  return _possibleConstructorReturn(_this, isNativeReflectConstruct() ? Reflect.construct(derived, args || [], _getPrototypeOf(_this).constructor) : derived.apply(_this, args));
}
/** @jsx jsx */
import { Component } from 'react';
import PropTypes from 'prop-types';
import pickBy from 'lodash/pickBy';
import propTypes, { defaultProps } from './propTypes';
import { jsx } from '@instructure/emotion';
import generateComponentTheme from './theme';
import generateStyle from './styles';
import { withStyleOverrides } from '@instructure/quiz-common';
var Canvas = (_dec = withStyleOverrides(generateStyle, generateComponentTheme), _dec(_class = (_Canvas = /*#__PURE__*/function (_Component) {
  function Canvas(props) {
    var _this2;
    _classCallCheck(this, Canvas);
    _this2 = _callSuper(this, Canvas, [props]);
    // these handlers shouldn't change, so set them once per initialization
    _defineProperty(_this2, "state", {
      isDrawing: false
    });
    _defineProperty(_this2, "refCanvas", function (node) {
      _this2.canvasElement = node;
    });
    // ===========
    //   ACTIONS
    // ===========
    _defineProperty(_this2, "drawShape", function (coordinates) {
      _this2.clearCanvas();
      _this2.props.drawShape(coordinates);
    });
    // ===========
    //   HANDLERS
    // ===========
    _defineProperty(_this2, "onMouseOut", function (e) {
      // the mouse out event is handled by default as a click/release on the exiting canvas border
      _this2.props.onMouseOut // eslint-disable-line no-unused-expressions
      ? _this2.props.onMouseOut(e) : function (e) {};
    });
    _this2.eventHandlers = _objectSpread({
      onMouseOut: _this2.onMouseOut
    }, pickBy(props, function (prop, propName) {
      return prop !== null && propName.startsWith('on');
    }));
    return _this2;
  }
  _inherits(Canvas, _Component);
  return _createClass(Canvas, [{
    key: "componentDidMount",
    value: function componentDidMount() {
      if (this.props.realRef) {
        this.props.realRef(this);
      }
      this.drawShape(this.props.coordinates);
    }
  }, {
    key: "componentDidUpdate",
    value: function componentDidUpdate() {
      this.drawShape(this.props.coordinates);
      if (this.isDrawing()) {
        this.canvasElement.focus();
      }
    }

    // ===========
    //   HELPERS
    // ===========
  }, {
    key: "isDrawing",
    value: function isDrawing() {
      return this.state.isDrawing;
    }
  }, {
    key: "getInitialCoordinate",
    value: function getInitialCoordinate() {
      return this.props.coordinates[0];
    }
  }, {
    key: "getLastCoordinate",
    value: function getLastCoordinate() {
      return this.props.coordinates[this.props.coordinates.length - 1];
    }
  }, {
    key: "getCurrentCoordinates",
    value: function getCurrentCoordinates(e) {
      var x = e.nativeEvent.offsetX;
      var y = e.nativeEvent.offsetY;
      return {
        x: x,
        y: y
      };
    }
  }, {
    key: "convertTouchCoordinates",
    value: function convertTouchCoordinates(touchEvent) {
      var rect = this.canvasElement.getBoundingClientRect();
      var x = touchEvent.changedTouches[0].pageX - rect.left;
      var y = touchEvent.changedTouches[0].pageY - rect.top;
      var evt = {
        nativeEvent: {
          offsetX: x,
          offsetY: y
        }
      };
      return evt;
    }
  }, {
    key: "focus",
    value: function focus() {
      this.canvasElement.focus();
    }
  }, {
    key: "clearCanvas",
    value: function clearCanvas() {
      var ctx = this.canvasElement.getContext('2d');
      ctx.clearRect(0, 0, this.canvasElement.width, this.canvasElement.height);
    }
  }, {
    key: "setStrokeStyle",
    value: function setStrokeStyle() {
      var color = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : this.props.styles.shapeColor;
      var ctx = this.canvasElement.getContext('2d');
      ctx.lineWidth = 2;
      ctx.strokeStyle = color;
    }
  }, {
    key: "setFillStyle",
    value: function setFillStyle() {
      var color = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : this.props.styles.shapeColor;
      var ctx = this.canvasElement.getContext('2d');
      ctx.globalAlpha = 0.5;
      ctx.fillStyle = color;
    }
  }, {
    key: "startDrawing",
    value: function startDrawing(e) {
      var initialCoordinate = this.getCurrentCoordinates(e);
      this.props.handleSetCoordinates([initialCoordinate], true);
      this.setState({
        isDrawing: true
      });
    }
  }, {
    key: "stopDrawing",
    value: function stopDrawing(coordinates) {
      this.props.handleSetCoordinates(coordinates, false);
      this.setState({
        isDrawing: false
      });
    }
  }, {
    key: "renderCanvas",
    value:
    // ===========
    //   RENDER
    // ===========

    function renderCanvas() {
      if (this.props.readOnly) {
        return jsx("canvas", {
          height: this.props.height,
          ref: this.refCanvas,
          width: this.props.width
        });
      }
      return jsx("canvas", Object.assign({
        css: this.props.styles.canvas,
        height: this.props.height,
        ref: this.refCanvas,
        tabIndex: "0",
        width: this.props.width,
        onBlur: this.onMouseOut
      }, this.eventHandlers));
    }
  }, {
    key: "render",
    value: function render() {
      return jsx("div", {
        css: this.props.styles.canvasWrapper
      }, this.renderCanvas());
    }
  }]);
}(Component), _defineProperty(_Canvas, "displayName", 'Canvas'), _defineProperty(_Canvas, "componentId", "Quizzes".concat(_Canvas.displayName)), _defineProperty(_Canvas, "propTypes", _objectSpread(_objectSpread({}, propTypes), {}, {
  realRef: PropTypes.func,
  drawShape: PropTypes.func.isRequired,
  onMouseOut: PropTypes.func,
  onMouseMove: PropTypes.func,
  onDoubleClick: PropTypes.func,
  onClick: PropTypes.func,
  onKeyPress: PropTypes.func,
  onMouseDown: PropTypes.func,
  onMouseUp: PropTypes.func,
  onTouchStart: PropTypes.func,
  onTouchMove: PropTypes.func,
  onTouchEnd: PropTypes.func,
  styles: PropTypes.object
})), _defineProperty(_Canvas, "defaultProps", _objectSpread({
  realRef: null,
  onMouseOut: null,
  onMouseMove: null,
  onDoubleClick: null,
  onClick: null,
  onKeyPress: null,
  onMouseDown: null,
  onMouseUp: null,
  onTouchStart: null,
  onTouchMove: null,
  onTouchEnd: null
}, defaultProps)), _Canvas)) || _class);
export { Canvas as default };