Dropdown with list of table's columns used within models-table.

It allows to toggle visibility for column sets or single column.

Columns that should not be hidden must have property mayBeHidden set to false.

Usage example:

<ModelsTable @data={{data}} @columns={{columns}} as |MT|>
  <MT.ColumnsDropdown />
  {{! .... }}
</ModelsTable>

Block usage example:

<ModelsTable @data={{data}} @columns={{columns}} as |MT|>
  <MT.ColumnsDropdown as |CD|>
    {{#if MT.columnDropdownOptions.showAll}}
      <button {{action MT.showAllColumns}}>Show all</button>
    {{/if}}
    {{#if MT.columnDropdownOptions.hideAll}}
      <button {{action MT.hideAllColumns}}>Hide all</button>
    {{/if}}
    {{#if MT.columnDropdownOptions.restoreDefaults}}
      <button {{action MT.restoreDefaultVisibility}}>Restore default visibility</button>
    {{/if}}
    {{#each MT.columnDropdownOptions.columnSets as |columnSet|}}
      <button {{action MT.toggleColumnSetVisibility columnSet}}>{{columnSet.label}}</button>
    {{/each}}
    {{#each MT.processedColumns as |column|}}
      {{#if column.mayBeHidden}}
        <button {{action MT.toggleHidden column}}>
          <i class={{if column.toggleColumnVisibility MT.themeInstance.columnVisibleIcon MT.themeInstance.columnHiddenIcon}}></i>
          {{column.title}}
        </button>
      {{/if}}
    {{/each}}
  </MT.ColumnsDropdown>
  {{! .... }}
</ModelsTable>