S2OJ/web/js/codemirror/addon/display/placeholder.js
Masco Skray 96d4a3ecf7 style(judger,web): move code out from subfolder "1"
Due to historical reasons, the code is in subfolder "1".
With SVN removal, we place the code back and remove the annoying "1" folder.
2019-06-14 23:34:41 +08:00

59 lines
1.9 KiB
JavaScript

// CodeMirror, copyright (c) by Marijn Haverbeke and others
// Distributed under an MIT license: http://codemirror.net/LICENSE
(function(mod) {
if (typeof exports == "object" && typeof module == "object") // CommonJS
mod(require("../../lib/codemirror"));
else if (typeof define == "function" && define.amd) // AMD
define(["../../lib/codemirror"], mod);
else // Plain browser env
mod(CodeMirror);
})(function(CodeMirror) {
CodeMirror.defineOption("placeholder", "", function(cm, val, old) {
var prev = old && old != CodeMirror.Init;
if (val && !prev) {
cm.on("blur", onBlur);
cm.on("change", onChange);
onChange(cm);
} else if (!val && prev) {
cm.off("blur", onBlur);
cm.off("change", onChange);
clearPlaceholder(cm);
var wrapper = cm.getWrapperElement();
wrapper.className = wrapper.className.replace(" CodeMirror-empty", "");
}
if (val && !cm.hasFocus()) onBlur(cm);
});
function clearPlaceholder(cm) {
if (cm.state.placeholder) {
cm.state.placeholder.parentNode.removeChild(cm.state.placeholder);
cm.state.placeholder = null;
}
}
function setPlaceholder(cm) {
clearPlaceholder(cm);
var elt = cm.state.placeholder = document.createElement("pre");
elt.style.cssText = "height: 0; overflow: visible";
elt.className = "CodeMirror-placeholder";
elt.appendChild(document.createTextNode(cm.getOption("placeholder")));
cm.display.lineSpace.insertBefore(elt, cm.display.lineSpace.firstChild);
}
function onBlur(cm) {
if (isEmpty(cm)) setPlaceholder(cm);
}
function onChange(cm) {
var wrapper = cm.getWrapperElement(), empty = isEmpty(cm);
wrapper.className = wrapper.className.replace(" CodeMirror-empty", "") + (empty ? " CodeMirror-empty" : "");
if (empty) setPlaceholder(cm);
else clearPlaceholder(cm);
}
function isEmpty(cm) {
return (cm.lineCount() === 1) && (cm.getLine(0) === "");
}
});