maxGraph/packages/html/stories/DynamicStyle.stories.js

/*
Copyright 2021-present The maxGraph project Contributors
Copyright (c) 2006-2020, JGraph Ltd

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

import { Graph, utils, constants, RubberBandHandler } from '@maxgraph/core';

import { globalTypes } from '../.storybook/preview';

export default {
  title: 'Styles/DynamicStyle',
  argTypes: {
    ...globalTypes,
    rubberBand: {
      type: 'boolean',
      defaultValue: true,
    },
  },
};

const Template = ({ label, ...args }) => {
  const container = document.createElement('div');
  container.style.position = 'relative';
  container.style.overflow = 'hidden';
  container.style.width = `${args.width}px`;
  container.style.height = `${args.height}px`;
  container.style.background = 'url(/images/grid.gif)';
  container.style.cursor = 'default';

  // Creates the graph inside the given container
  const graph = new Graph(container);

  // Disables moving of edge labels in this examples
  graph.edgeLabelsMovable = false;

  // Enables rubberband selection
  if (args.rubberBand) new RubberBandHandler(graph);

  // Needs to set a flag to check for dynamic style changes,
  // that is, changes to styles on cells where the style was
  // not explicitely changed using mxStyleChange
  graph.getView().updateStyle = true;

  // Overrides Cell.getStyle to return a specific style
  // for edges that reflects their target terminal (in this case
  // the strokeColor will be equal to the target's fillColor).

  const getStyle = function () {
    // TODO super cannot be used here
    // let style = super.getStyle();
    let style = {};

    if (this.isEdge()) {
      const target = this.getTerminal(false);

      if (target != null) {
        const targetStyle = graph.getCurrentCellStyle(target);
        const fill = utils.getValue(targetStyle, 'fillColor');

        if (fill != null) {
          style.strokeColor = fill;
        }
      }
    } else if (this.isVertex()) {
      const geometry = this.getGeometry();
      if (geometry != null && geometry.width > 80) {
        style.fillColor = 'green';
      }
    }
    return style;
  };

  // Gets the default parent for inserting new cells. This
  // is normally the first child of the root (ie. layer 0).
  const parent = graph.getDefaultParent();

  // Adds cells to the model in a single step
  graph.batchUpdate(() => {
    const v1 = graph.insertVertex({
      parent,
      value: 'Hello,',
      position: [20, 20],
      size: [80, 30],
      style: { fillColor: 'green' },
    });
    v1.getStyle = getStyle;

    const v2 = graph.insertVertex({
      parent,
      value: 'World!',
      position: [200, 150],
      size: [80, 30],
      style: { fillColor: 'blue' },
    });
    v2.getStyle = getStyle;

    const v3 = graph.insertVertex({
      parent,
      value: 'World!',
      position: [20, 150],
      size: [80, 30],
      style: { fillColor: 'red' },
    });
    v3.getStyle = getStyle;

    const e1 = graph.insertEdge({
      parent,
      value: 'Connect',
      source: v1,
      target: v2,
      style: {
        perimeterSpacing: 4,
        strokeWidth: 4,
        labelBackgroundColor: 'white',
        fontStyle: 1,
      },
    });
    e1.getStyle = getStyle;
  });

  return container;
};

export const Default = Template.bind({});