Add default keymap icon hint

src/components/keymap/header/keymap-header.component.ts

@@ -1,4 +1,4 @@
-import { Component, ElementRef, Input, Renderer, ViewChild } from '@angular/core';
+import { ChangeDetectionStrategy, Component, ElementRef, Input, OnChanges, Renderer, ViewChild } from '@angular/core';
 
 import { Store } from '@ngrx/store';
 
@@ -10,15 +10,22 @@ import { KeymapActions } from '../../../store/actions';
 @Component({
     selector: 'keymap-header',
     template: require('./keymap-header.component.html'),
-    styles: [require('./keymap-header.component.scss')]
+    styles: [require('./keymap-header.component.scss')],
+    changeDetection: ChangeDetectionStrategy.OnPush
 })
-export class KeymapHeaderComponent {
+export class KeymapHeaderComponent implements OnChanges {
     @Input() keymap: Keymap;
     @ViewChild('name') keymapName: ElementRef;
     @ViewChild('abbr') keymapAbbr: ElementRef;
 
+    private starTitle: string;
+
     constructor(private store: Store<AppState>, private renderer: Renderer) { }
 
+    ngOnChanges() {
+        this.setTitle();
+    }
+
     setDefault() {
         if (!this.keymap.isDefault) {
             this.store.dispatch(KeymapActions.setDefault(this.keymap.abbreviation));
@@ -51,4 +58,10 @@ export class KeymapHeaderComponent {
         newAbbr = newAbbr.toUpperCase();
         this.store.dispatch(KeymapActions.editKeymapAbbr(this.keymap.abbreviation, newAbbr));
     }
+
+    setTitle(): void {
+        this.starTitle = this.keymap.isDefault
+        ? 'This is the default keymap which gets activated when powering the keyboard.'
+        : 'Makes this keymap the default keymap which gets activated when powering the keyboard.';
+    }
 }