fix(): fixed style flickering (closes #71)

Author: marhi

e2e/app.e2e.ts

@@ -464,5 +464,10 @@ describe('bterm launch', function() {
     });
   }
 
-})
+  it('should inject a style element into head', () => {
+  return this.app.client.waitUntilWindowLoaded()
+      .then(() => this.app.client.elements('head style'))
+      .then(result => expect(result.value.length).to.equal(1));
+  });
 
+});

src/app/components/window-top/window-top.component.ts

@@ -145,7 +145,7 @@ export class WindowTopComponent implements OnInit {
             return([ mm.screenX - startX, mm.screenY - startY ]);
           }
         )
-        .filter(x => x[0] != 0 || x[1] != 0)
+        .filter(x => x[0] !== 0 || x[1] !== 0)
         .takeUntil(mouseUp$)
       }
     )

src/utils.ts

@@ -87,14 +87,16 @@ export class CssBuilder {
     return this.css;
   }
 
-  inject(): void {
+  inject(seamless: boolean = true): void {
     this.build();
-    if (this.styleEl) { this.styleEl.remove(); }
+    if (!seamless && this.styleEl) { this.styleEl.remove(); }
 
-    this.styleEl = document.createElement('style') as HTMLStyleElement;
-    this.styleEl.setAttribute('type', 'text/css');
-    this.styleEl.innerHTML = this.css;
+    let newStyle: HTMLStyleElement = document.createElement('style') as HTMLStyleElement;
+    newStyle.setAttribute('type', 'text/css');
+    newStyle.innerHTML = this.css;
 
-    setTimeout(() => document.querySelector('head').appendChild(this.styleEl));
+    document.querySelector('head').appendChild(newStyle);
+    if (this.styleEl) { this.styleEl.remove(); }
+    this.styleEl = newStyle;
   }
 }