Add contour, geojson, and heatmap example image

Signed-off-by: Willie Hung <[email protected]>

superset-frontend/plugins/legacy-preset-chart-deckgl/src/layers/Contour/index.ts

@@ -20,13 +20,15 @@ import { t, ChartMetadata, ChartPlugin } from '@superset-ui/core';
 import transformProps from '../../transformProps';
 import controlPanel from './controlPanel';
 import thumbnail from './images/thumbnail.png';
+import example from './images/example.png';
 
 const metadata = new ChartMetadata({
   category: t('Map'),
   credits: ['https://uber.github.io/deck.gl'],
   description: t(
     'Uses Gaussian Kernel Density Estimation to visualize spatial distribution of data',
   ),
+  exampleGallery: [{ url: example }],
   name: t('deck.gl Countour'),
   thumbnail,
   useLegacyApi: true,

superset-frontend/plugins/legacy-preset-chart-deckgl/src/layers/Geojson/index.ts

@@ -18,6 +18,7 @@
  */
 import { t, ChartMetadata, ChartPlugin } from '@superset-ui/core';
 import thumbnail from './images/thumbnail.png';
+import example from './images/example.png';
 import transformProps from '../../transformProps';
 import controlPanel from './controlPanel';
 
@@ -27,6 +28,7 @@ const metadata = new ChartMetadata({
   description: t(
     'The GeoJsonLayer takes in GeoJSON formatted data and renders it as interactive polygons, lines and points (circles, icons and/or texts).',
   ),
+  exampleGallery: [{ url: example }],
   name: t('deck.gl Geojson'),
   thumbnail,
   useLegacyApi: true,

superset-frontend/plugins/legacy-preset-chart-deckgl/src/layers/Heatmap/index.ts

@@ -20,13 +20,15 @@ import { t, ChartMetadata, ChartPlugin } from '@superset-ui/core';
 import transformProps from '../../transformProps';
 import controlPanel from './controlPanel';
 import thumbnail from './images/thumbnail.png';
+import example from './images/example.png';
 
 const metadata = new ChartMetadata({
   category: t('Map'),
   credits: ['https://uber.github.io/deck.gl'],
   description: t(
     'Uses Gaussian Kernel Density Estimation to visualize spatial distribution of data',
   ),
+  exampleGallery: [{ url: example }],
   name: t('deck.gl Heatmap'),
   thumbnail,
   useLegacyApi: true,