feat(uui-input-file): Only show add button when multiple or no file selected (#395)

* Update uui-input-file.element.ts

Only show add button when multiple or no file selected

* missing import

---------

Co-authored-by: Jacob Overgaard <[email protected]>

Author: nathanwoulfe

packages/uui-input-file/lib/uui-input-file.element.ts

@@ -1,6 +1,6 @@
 import { defineElement } from '@umbraco-ui/uui-base/lib/registration';
 import { property, query, state } from 'lit/decorators.js';
-import { css, html, LitElement } from 'lit';
+import { css, html, LitElement, nothing } from 'lit';
 import { UUIFileDropzoneElement } from '@umbraco-ui/uui-file-dropzone/lib';
 import { FormControlMixin } from '@umbraco-ui/uui-base/lib/mixins';
 import { demandCustomElement } from '@umbraco-ui/uui-base/lib/utils';
@@ -265,11 +265,13 @@ export class UUIInputFileElement extends FormControlMixin(LitElement) {
         label="Drop files here"></uui-file-dropzone>
       <div id="files">
         ${this._renderFiles()}
-        <uui-button
-          @click=${this._handleClick}
-          id="add-button"
-          look="placeholder"
-          label="Add"></uui-button>
+        ${this._files.length === 0 || this.multiple
+          ? html`<uui-button
+              @click=${this._handleClick}
+              id="add-button"
+              look="placeholder"
+              label="Add"></uui-button>`
+          : nothing}
       </div>
     `;
   }