added examples

2017-05-19 02:21:50 +02:00
parent 0a321610aa
commit 42abcc897c
25 changed files with 753 additions and 2 deletions
--- a/examples/chat/index.html
+++ b/examples/chat/index.html
@@ -0,0 +1,18 @@
+<!DOCTYPE html>
+<html>
+  <body>
+    <style>
+      #chat p span {
+        color: blue;
+      }
+    </style>
+    <div id="chat"></div>
+    <form id="chatform">
+      <input name="username" type="text" style="width:15%;">
+      <input name="message" type="text" style="width:60%;">
+      <input type="submit" value="Send">
+    </form>
+    <script src="../bower_components/yjs/y.js"></script>
+    <script src="./index.js"></script>
+  </body>
+</html>
--- a/examples/chat/index.js
+++ b/examples/chat/index.js
@@ -0,0 +1,75 @@
+/* @flow */
+/* global Y */
+
+// initialize a shared object. This function call returns a promise!
+Y({
+  db: {
+    name: 'memory'
+  },
+  connector: {
+    name: 'websockets-client',
+    room: 'chat-example'
+  },
+  sourceDir: '/bower_components',
+  share: {
+    chat: 'Array'
+  }
+}).then(function (y) {
+  window.yChat = y
+  // This functions inserts a message at the specified position in the DOM
+  function appendMessage(message, position) { 
+    var p = document.createElement('p')
+    var uname = document.createElement('span')
+    uname.appendChild(document.createTextNode(message.username + ": "))
+    p.appendChild(uname)
+    p.appendChild(document.createTextNode(message.message))
+    document.querySelector('#chat').insertBefore(p, chat.children[position] || null)
+  }
+  // This function makes sure that only 7 messages exist in the chat history.
+  // The rest is deleted
+  function cleanupChat () {
+    var len
+    while ((len = y.share.chat.length) > 7) {
+      y.share.chat.delete(0)        
+    }
+  }
+  // Insert the initial content
+  y.share.chat.toArray().forEach(appendMessage)
+  cleanupChat()
+  
+  // whenever content changes, make sure to reflect the changes in the DOM
+  y.share.chat.observe(function (event) {
+    if (event.type === 'insert') {
+      for (var i = 0; i < event.length; i++) {
+        appendMessage(event.values[i], event.index + i)
+      }
+    } else if (event.type === 'delete') {
+      for (var i = 0; i < event.length; i++) {
+        chat.children[event.index].remove()
+      }
+    }
+    // concurrent insertions may result in a history > 7, so cleanup here
+    cleanupChat()
+  })
+  document.querySelector('#chatform').onsubmit = function (event) {
+    // the form is submitted
+    var message = {
+      username: this.querySelector("[name=username]").value,
+      message: this.querySelector("[name=message]").value
+    }
+    if (message.username.length > 0 && message.message.length > 0) {
+      if (y.share.chat.length > 6) {
+        // If we are goint to insert the 8th element, make sure to delete first.
+        y.share.chat.delete(0)
+      }
+      // Here we insert a message in the shared chat type.
+      // This will call the observe function (see line 40)
+      // and reflect the change in the DOM
+      y.share.chat.push([message])
+      this.querySelector("[name=message]").value = ""
+    }
+    // Do not send this form!
+    event.preventDefault()
+    return false
+  }
+})