fix(button): fix ssr

A-l-y-l-e · Nov 23, 2018 · 5e5aede · 5e5aede
1 parent 28f5088
commit 5e5aede
Showing 1 changed file with 15 additions and 11 deletions.
diff --git a/src/lib/button/button.ts b/src/lib/button/button.ts
@@ -188,18 +188,22 @@ export class LyButton extends LyButtonMixinBase implements OnChanges, OnInit, Af
     if (this.disableRipple === null) {
       this.disableRipple = DEFAULT_DISABLE_RIPPLE;
     }
-    this._focusState.listen(this._el).subscribe((event) => {
-      if (this._onFocusByKeyboardState === true) {
-        this._renderer.removeClass(this._el.nativeElement, this.classes.onFocusByKeyboard);
-        this._onFocusByKeyboardState = false;
-      }
-      if (event.by === 'keyboard') {
-        if (event.event.type === 'focus') {
-          this._onFocusByKeyboardState = true;
-          this._renderer.addClass(this._el.nativeElement, this.classes.onFocusByKeyboard);
+
+    const focusState = this._focusState.listen(this._el);
+    if (focusState) {
+      focusState.subscribe((event) => {
+        if (this._onFocusByKeyboardState === true) {
+          this._renderer.removeClass(this._el.nativeElement, this.classes.onFocusByKeyboard);
+          this._onFocusByKeyboardState = false;
         }
-      }
-    });
+        if (event.by === 'keyboard') {
+          if (event.event.type === 'focus') {
+            this._onFocusByKeyboardState = true;
+            this._renderer.addClass(this._el.nativeElement, this.classes.onFocusByKeyboard);
+          }
+        }
+      });
+    }
   }
 
   public focus() {