add tooltip viewer

src/components/TooltipViewer.js

@@ -0,0 +1,45 @@
+import React, { Component } from 'react';
+import PropTypes from 'prop-types';
+import { connect } from 'react-redux';
+
+import withWidth from '@material-ui/core/withWidth';
+
+import { Card } from '@material-ui/core';
+import * as Blockly from 'blockly'
+import CardContent from '@material-ui/core/CardContent';
+
+import Typography from '@material-ui/core/Typography';
+import ReactMarkdown from 'react-markdown';
+import Link from '@material-ui/core/Link'
+import CardActions from '@material-ui/core/CardActions';
+import Button from '@material-ui/core/Button';
+
+class TooltipViewer extends Component {
+
+
+  render() {
+
+    return (
+      <Card style={{ height: '100%', margin: '1vH 0 0 0', maxHeight: '19vH' }} ref={this.myDiv}>
+        <CardContent>
+          <Typography variant="h5" component="h2">
+            Hilfe
+        </Typography>
+          <Typography variant="body1" component="p">
+            <ReactMarkdown>{this.props.tooltip}</ReactMarkdown>
+          </Typography>
+        </CardContent>
+      </Card>
+    );
+  };
+}
+
+TooltipViewer.propTypes = {
+  tooltip: PropTypes.string.isRequired
+};
+
+const mapStateToProps = state => ({
+  tooltip: state.workspace.code.tooltip
+});
+
+export default connect(mapStateToProps, null)(withWidth()(TooltipViewer));