diff options
| -rw-r--r-- | html/whiteboard.js | 32 |
1 files changed, 28 insertions, 4 deletions
diff --git a/html/whiteboard.js b/html/whiteboard.js index ae20c5b..7777d4e 100644 --- a/html/whiteboard.js +++ b/html/whiteboard.js @@ -99,10 +99,17 @@ function init_board() { reader = new FileReader(); reader.onload = function() { var board = document.getElementById("board"); - board.innerHTML = reader.result; + var pos = reader.result.indexOf('\x01'); + if (pos == -1) { // not found + board.value = reader.result; + } else { + board.value = reader.result.substr(0, pos) + reader.result.substr(pos + 1); + } + textAreaSetPos("board", pos); // Initialization done. Now we can start modifying. board.addEventListener("input", function() {on_modify(); }); + board.addEventListener("selectionchange", function() {on_modify(); }); // Initialization done. Now we can start modifying. document.addEventListener("mousemove", function() {timer.reset(); }); @@ -243,7 +250,7 @@ function on_modify() requestElement.appendChild(idElement); var dataElement = xmlDocument.createElement("data"); - dataElement.appendChild(document.createTextNode(document.getElementById("board").value)); + dataElement.appendChild(document.createTextNode(addPos(document.getElementById("board").value, document.getElementById("board").selectionStart))); requestElement.appendChild(dataElement); xhr.open("POST", "whiteboard.fcgi", true); @@ -263,6 +270,17 @@ function checksum32(s) { return (result & 0x7FFFFFFF) | 0; } +function textAreaSetPos(id, pos) +{ + document.getElementById(id).selectionStart = pos; + document.getElementById(id).selectionEnd = pos; +} + +function addPos(s, pos) +{ + return s.substr(0, pos) + '\x01' + s.substr(pos); +} + // gets called by regular polling function checkupdate() { var xhr = new XMLHttpRequest(); @@ -288,7 +306,13 @@ function checkupdate() { reader = new FileReader(); reader.onload = function() { var board = document.getElementById("board"); - board.value = reader.result; + var pos = reader.result.indexOf('\x01'); + if (pos == -1) { // not found + board.value = reader.result; + } else { + board.value = reader.result.substr(0, pos) + reader.result.substr(pos + 1); + } + textAreaSetPos("board", pos); } reader.readAsBinaryString(file); @@ -311,7 +335,7 @@ function checkupdate() { requestElement.appendChild(idElement); var checksumElement = xmlDocument.createElement("checksum"); - checksumElement.appendChild(document.createTextNode(checksum32(document.getElementById("board").value))); + checksumElement.appendChild(document.createTextNode(checksum32(addPos(document.getElementById("board").value, document.getElementById("board").selectionStart)))); requestElement.appendChild(checksumElement); xhr.open("POST", "whiteboard.fcgi", true); |