update default values when chart type changes

reports/static/reports/js/reportImg.js

@@ -145,11 +145,32 @@ function change(newType) {
     // Remove the old chart and all its event handles
     if (myChart) {
         myChart.destroy();
-
     }
 
     // Chart.js modifies the object you pass in. Pass a copy of the object so we can use the original object later
 
+
+
+
+    // -------------- set last values when the chart was destroyed ------
+    let selectedLayers = getSelectedLayersName().map( layerName => {
+        const layerCheckbox = $(':checkbox[value='+layerName+']');
+        return layerCheckbox.parent().attr('id')
+    });
+    selectedLayers = selectedLayers.filter(layerId => layerId!=null);
+    selectedLayers = selectedLayers.map(layerId => layerId.replace('sclcheck-', '').replace('-', ' '));
+
+    config.data.datasets.forEach(data => {
+        const label = data.label.toLowerCase().replace('-', ' ');
+        data.hidden = true;
+
+        if (selectedLayers.includes(label)) {
+            data.hidden = false;
+        }
+    })
+    // -------------------------------------------------------------------
+
+
     var temp = jQuery.extend(true, {}, config);
     if (newType == "stackedBar"){
         temp.type = "bar";