Add option to disable workspace auto focus

Resolve #40

Signed-off-by: Songlin Jiang <songlin.jiang@csc.fi>

Author: HollowMan6

README.md

@@ -40,6 +40,9 @@ options = {
   // Keep the fields of multiple selected same-type blocks with the same value
   multiFieldUpdate: true,
 
+  // Auto focus the workspace when the mouse enters.
+  workspaceAutoFocus: true,
+
   // Use custom icon for the multi select controls.
   multiselectIcon: {
     hideIcon: false,

src/multiselect.js

@@ -52,7 +52,8 @@ export class Multiselect {
     this.onFocusOutWrapper_ = Blockly.browserEvents.conditionalBind(
         injectionDiv, 'focusout', this, this.onBlur_);
     injectionDiv.addEventListener('mouseenter', () => {
-      if (document.activeElement === this.workspace_.svgGroup_.parentElement ||
+      if (options.workspaceAutoFocus === false ||
+          document.activeElement === this.workspace_.svgGroup_.parentElement ||
           document.activeElement.nodeName.toLowerCase() === 'input' ||
           document.activeElement.nodeName.toLowerCase() === 'textarea') {
         return;