Sascha Schulz
2023-08-15 935b368767b1c0a665c5657c9c7815e71c36633d
index.html
@@ -2386,6 +2386,416 @@
                     </code>
                  </pre>
               </section>
               <section>
                  <h3>Map</h3>
                  <ul>
                     <li>auch als "assoziatives Array" bezeichnet</li>
                     <li>iterierbare Liste</li>
                     <li>ideal zur Assoziation von z.B. Hashes zu Objekt-Instanzen o.ä.</li>
                     <li>nutzbar ab es6 / es2015</li>
                     <li>löst herkömmliche Objekte als Hash-Map ab</li>
                  </ul>
               </section>
               <section>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        const m = new Map();
                        m.set("a", 0);
                        m.set("a", 1);
                        m.set("b", 2);
                        m.has("c"); // => false
                        m.delete("b");
                        console.log(m.get("a")); // => 1
                     </code>
                  </pre>
               </section>
               <section>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        m.forEach((k, v) => console.log(k, v)) // => "a" 1 ...
                        for (const entry of m.entries()) {
                           console.log(entry); // => ["a", 1] ...
                        }
                        for (const key of m.keys()) {
                           console.log(key); // => "a" ...
                        }
                        for (const value of m.values()) {
                           console.log(value); // => "1" ...
                        }
                     </code>
                  </pre>
               </section>
               <section>
                  <h3>Set</h3>
                  <ul>
                     <li>enthält nur einzigartige Werte</li>
                     <li>iterierbare Liste</li>
                     <li>ideale Struktur, wenn einzelne Werte einzigartig sein sollen</li>
                     <li>nutzbar ab es6 / es2015</li>
                     <li>löst individuelle Lösungen mittels Arrays und Array.prototype.indexOf o.ä. ab</li>
                  </ul>
               </section>
               <section>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        const s = new Set();
                        s.add("a");
                        s.add("a");
                        s.has("c"); // => false
                        s.delete("a");
                        console.log(s.size); // => 0
                     </code>
                  </pre>
               </section>
               <section>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        s.forEach((k, v) => console.log(k, v)) // => "a" "a" ...
                        for (const entry of m.entries()) {
                           console.log(entry); // => ["a", "a"] ...
                        }
                        for (const key of m.keys()) {
                           console.log(key); // => "a"...
                        }
                        for (const value of s.values()) {
                           console.log(value); // => "a" ...
                        }
                     </code>
                  </pre>
               </section>
               <section>
                  <h3>DOM-Events</h3>
                  <ul>
                     <li>funktionale Ausführung von Code</li>
                     <li>Trigger können Klicks, Scrollen, Tastendrücke, Änderungen der Fenstergröße usw. sein</li>
                  </ul>
               </section>
               <section>
                  <img data-src="/assets/images/dom-events.svg">
               </section>
               <section>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        function doSomething(e) {
                           console.log("capture");
                        }
                        function click(e) {
                           console.log("bubble");
                        }
                        div.addEventListener("click", doSomething, true);
                        button.addEventListener("click", click, false /* default */);
                     </code>
                  </pre>
                  <pre>
                     <code class="bash" data-trim data-line-numbers>
                        capturing
                        bubble
                     </code>
                  </pre>
               </section>
               <section>
                  <p>Aufgabe: Erweitere das vorherige Beispiel so, dass das div-Element einen weiteren Click-Handler bekommt,
                  der den Text "bubble2" anzeigt, nachdem "bubble" in der Konsole geloggt wurde.</p>
                  <p>Erwartete Ausgabe:</p>
                  <pre>
                     <code class="bash" data-trim data-line-numbers>
                        capturing
                        bubble
                        bubble2
                     </code>
                  </pre>
               </section>
               <section>
                  <p>Lösung:</p>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        function doSomething(e) {
                           console.log("capture");
                        }
                        // neu
                        function doSomething2(e) {
                           console.log("bubble2");
                        }
                        function click(e) {
                           console.log("bubble");
                        }
                        div.addEventListener("click", doSomething, true);
                        div.addEventListener("click", doSomething2, false); // neu
                        button.addEventListener("click", click, false /* default */);
                     </code>
                  </pre>
               </section>
               <section>
                  Die Bubble-Phase stoppen
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        function click(e) {
                           e.stopPropagation()
                        }
                     </code>
                  </pre>
               </section>
               <section>
                  <p>Aufgabe: Ändere das Ergebnis des vorherigen Beispiels, sodass die Bubble-Phase auf Ebene des button-Elements gestoppt wird. Was ändert sich in der Ausgabe?</p>
               </section>
               <section>
                  <p>Lösung:</p>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        function doSomething(e) {
                           console.log("capture");
                        }
                        function doSomething2(e) {
                           console.log("bubble2");
                        }
                        function click(e) {
                           e.stopPropagation();
                           console.log("bubble");
                        }
                        div.addEventListener("click", doSomething, true);
                        div.addEventListener("click", doSomething2, false);
                        button.addEventListener("click", click, false /* default */);
                     </code>
                  </pre>
               </section>
               <section>
                  Events programatisch triggern:
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        button.dispatchEvent(new Event("click"));
                     </code>
                  </pre>
               </section>
               <section>
                  Events sind synchron:
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        doSomethingElse();
                        button.dispatchEvent(new Event("click"));
                        doAnotherThing(); // wird erst ausgeführt, wenn zuvor alle Event-Handler fertig sind
                     </code>
                  </pre>
               </section>
               <section>
                  <h3>Strings</h3>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        const empty1 = "";
                        const empty1 = '';
                        const s1 = 'abc';
                        const s2 = "abc";
                        const s3 = 'a"b"c';
                        const s4 = "a\"b\"c";
                        const s5 = 'a\'b\'c';
                        const s6 = "a'b'c";
                        const s7 = `a'b'"c"`;
                     </code>
                  </pre>
               </section>
               <section>
                  <h5>Strings zusammenfügen</h5>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        const age = 10;
                        // Konkatenation
                        const s = "My age is " + number + "!";
                        // Interpolation
                        const s = `My age is ${number}!`;
                        // => "My age is 10!"
                     </code>
                  </pre>
               </section>
               <section>
                  <h5>Template Strings</h5>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        function sayHello() {
                           return "Hello";
                        }
                        let interpolation = `${sayHello()}`;
                        // => "Hello"
                        interpolation = `5 + 5 = ${5+5}`;
                        // => "5 + 5 = 10"
                     </code>
                  </pre>
               </section>
               <section>
                  lit
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        return html`<div>hello world!</div>`
                     </code>
                  </pre>
               </section>
               <section>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        function myTag() {
                           console.log(arguments);
                           // return 5;
                           // return true;
                           return "abc";
                        }
                        let interpolation = myTag`a ${5} b ${6} c`;
                        // => "abc"
                     </code>
                  </pre>
                  <pre>
                     <code class="bash" data-trim data-line-numbers>
                        Arguments(3) [Array(3), 5, 6]
                           0 : (3) ['a ', ' b ', ' c', raw: Array(3)]
                           1 : 5
                           2 : 6
                     </code>
                  </pre>
               </section>
               <section>
                  <h5>Aufgabe</h5>
                  <p>Schreibe ein Tag, welches die Zahlen aus den dynamischen Ausdrücken zusammenrechnet (<code>strings.js</code>)</p>
               </section>
               <section>
                  <h5>Lösung</h5>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        function add(parts, ...numbers) {
                           return numbers.reduce((p, c) => p + c, 0);
                        }
                        let sum = add`a ${5} b ${6} c`;
                        console.log(sum);
                        // => 11
                     </code>
                  </pre>
               </section>
               <section>
                  <h5>Rest-Operator</h5>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        function add(...numbers) {
                           return numbers.reduce((p, c) => p + c, 0);
                        }
                        add(1, 2, 3); // => 6
                     </code>
                  </pre>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        const o1 = {a: 1, b: 2};
                        const o2 = {x: 5, y: 6, ...o1};
                     </code>
                  </pre>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        const a1 = [4, 5, 6];
                        const a2 = [1, 2, 3, ...a1];
                     </code>
                  </pre>
               </section>
               <section>
                  <h3>Relevante Browser-APIs</h3>
               </section>
               <section>
                  <h5>window</h5>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        window.innerWidth; // innere Auflösung des sichtbaren Fensters
                        window.innerHeight;
                        window.outerWidth; // äußere Auflösung des Browserfensters inklusive Adresszeile usw.
                        window.outerHeight;
                        window.addEventListener(); // Events an das äußerste "Dach"-Element hängen
                     </code>
                  </pre>
               </section>
               <section>
                  <h5>location</h5>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        location.href; // aktuelle URL
                        location.host; // aktuelle Domain, z.B. "www.google.de"
                        location.protocol; // aktuelles Protokoll, z.B. "https:"
                     </code>
                  </pre>
               </section>
               <section>
                  <h5>Navigator</h5>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        navigator.language; // bevorzugte Browsersprache, z.B. "de"
                        navigator.userAgent; // z.B. "Mozilla/5.0 (Linux; Android 6.0; Nexus 5 Build/MRA58N) [...]"
                        navigator
                           .mediaDevices
                           .getDisplayMedia(); // Fordere Erlaubis zum Streamen von Anwendungen oder Bildschirmen an
                     </code>
                  </pre>
               </section>
               <section>
                  <h5>Document</h5>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        document.body; // &lt;body>-Element der Seite
                        document.activeElement; // aktives Element der Seite, welche gerade den Fokus besitzt
                        document.cookie; // für die aktuelle Seite gesetzte Cookies
                        document.execCommand("copy"); // Texte in die Zwischenablage zu schreiben
                        document.createElement("div"); // erzeuge neues DOM-Element mit angegebenen Tag
                     </code>
                  </pre>
               </section>
               <section>
                  <h5>LocalStorage</h5>
                  <pre>
                     <code class="js" data-trim data-line-numbers>
                        // auf 5MB Daten pro Domain begrenzt
                        localStorage.getItem(key); // Element holen
                        localStorage.setItem(key, value); // Element setzen
                        localStorage.removeItem(key); // Element entfernen
                     </code>
                  </pre>
               </section>
            </section>
         </div>
      </div>
@@ -2402,7 +2812,7 @@
            hash: true,
            slideNumber: "c/t",
            transition: "fade",
            // Learn about plugins: https://revealjs.com/plugins/
            plugins: [ RevealMarkdown, RevealHighlight, RevealNotes ]
         });