web/admin: improve empty state

Signed-off-by: Jens Langhammer <jens.langhammer@beryju.org>

# Conflicts:
#	web/src/elements/table/TablePage.ts
#	web/src/pages/applications/ApplicationListPage.ts

web/src/elements/table/TablePage.ts

@@ -1,3 +1,5 @@
+import { t } from "@lingui/macro";
+
 import { CSSResult } from "lit";
 import { TemplateResult, html } from "lit";
 import { ifDefined } from "lit/directives/if-defined.js";
@@ -26,6 +28,24 @@ export abstract class TablePage<T> extends Table<T> {
         return html``;
     }
 
+    renderEmpty(inner?: TemplateResult): TemplateResult {
+        return super.renderEmpty(html`
+            ${inner
+                ? inner
+                : html`<ak-empty-state icon=${this.pageIcon()} header="${t`No objects found.`}">
+                      <div slot="body">${this.renderObjectCreate()}</div>
+                  </ak-empty-state>`}
+        `);
+    }
+
+    renderObjectCreate(): TemplateResult {
+        return html``;
+    }
+
+    renderToolbar(): TemplateResult {
+        return html`${this.renderObjectCreate()}${super.renderToolbar()}`;
+    }
+
     render(): TemplateResult {
         return html`<ak-page-header
                 icon=${this.pageIcon()}