jsoneditor/src_old/js/ContextMenu.js

458 lines
13 KiB
JavaScript

'use strict';
var util = require('./util');
/**
* A context menu
* @param {Object[]} items Array containing the menu structure
* TODO: describe structure
* @param {Object} [options] Object with options. Available options:
* {function} close Callback called when the
* context menu is being closed.
* @constructor
*/
function ContextMenu (items, options) {
this.dom = {};
var me = this;
var dom = this.dom;
this.anchor = undefined;
this.items = items;
this.eventListeners = {};
this.selection = undefined; // holds the selection before the menu was opened
this.onClose = options ? options.close : undefined;
// create root element
var root = document.createElement('div');
root.className = 'jsoneditor-contextmenu-root';
dom.root = root;
// create a container element
var menu = document.createElement('div');
menu.className = 'jsoneditor-contextmenu';
dom.menu = menu;
root.appendChild(menu);
// create a list to hold the menu items
var list = document.createElement('ul');
list.className = 'jsoneditor-menu';
menu.appendChild(list);
dom.list = list;
dom.items = []; // list with all buttons
// create a (non-visible) button to set the focus to the menu
var focusButton = document.createElement('button');
dom.focusButton = focusButton;
var li = document.createElement('li');
li.style.overflow = 'hidden';
li.style.height = '0';
li.appendChild(focusButton);
list.appendChild(li);
function createMenuItems (list, domItems, items) {
items.forEach(function (item) {
if (item.type == 'separator') {
// create a separator
var separator = document.createElement('div');
separator.className = 'jsoneditor-separator';
li = document.createElement('li');
li.appendChild(separator);
list.appendChild(li);
}
else {
var domItem = {};
// create a menu item
var li = document.createElement('li');
list.appendChild(li);
// create a button in the menu item
var button = document.createElement('button');
button.className = item.className;
domItem.button = button;
if (item.title) {
button.title = item.title;
}
if (item.click) {
button.onclick = function (event) {
event.preventDefault();
me.hide();
item.click();
};
}
li.appendChild(button);
// create the contents of the button
if (item.submenu) {
// add the icon to the button
var divIcon = document.createElement('div');
divIcon.className = 'jsoneditor-icon';
button.appendChild(divIcon);
button.appendChild(document.createTextNode(item.text));
var buttonSubmenu;
if (item.click) {
// submenu and a button with a click handler
button.className += ' jsoneditor-default';
var buttonExpand = document.createElement('button');
domItem.buttonExpand = buttonExpand;
buttonExpand.className = 'jsoneditor-expand';
buttonExpand.innerHTML = '<div class="jsoneditor-expand"></div>';
li.appendChild(buttonExpand);
if (item.submenuTitle) {
buttonExpand.title = item.submenuTitle;
}
buttonSubmenu = buttonExpand;
}
else {
// submenu and a button without a click handler
var divExpand = document.createElement('div');
divExpand.className = 'jsoneditor-expand';
button.appendChild(divExpand);
buttonSubmenu = button;
}
// attach a handler to expand/collapse the submenu
buttonSubmenu.onclick = function (event) {
event.preventDefault();
me._onExpandItem(domItem);
buttonSubmenu.focus();
};
// create the submenu
var domSubItems = [];
domItem.subItems = domSubItems;
var ul = document.createElement('ul');
domItem.ul = ul;
ul.className = 'jsoneditor-menu';
ul.style.height = '0';
li.appendChild(ul);
createMenuItems(ul, domSubItems, item.submenu);
}
else {
// no submenu, just a button with clickhandler
button.innerHTML = '<div class="jsoneditor-icon"></div>' + item.text;
}
domItems.push(domItem);
}
});
}
createMenuItems(list, this.dom.items, items);
// TODO: when the editor is small, show the submenu on the right instead of inline?
// calculate the max height of the menu with one submenu expanded
this.maxHeight = 0; // height in pixels
items.forEach(function (item) {
var height = (items.length + (item.submenu ? item.submenu.length : 0)) * 24;
me.maxHeight = Math.max(me.maxHeight, height);
});
}
/**
* Get the currently visible buttons
* @return {Array.<HTMLElement>} buttons
* @private
*/
ContextMenu.prototype._getVisibleButtons = function () {
var buttons = [];
var me = this;
this.dom.items.forEach(function (item) {
buttons.push(item.button);
if (item.buttonExpand) {
buttons.push(item.buttonExpand);
}
if (item.subItems && item == me.expandedItem) {
item.subItems.forEach(function (subItem) {
buttons.push(subItem.button);
if (subItem.buttonExpand) {
buttons.push(subItem.buttonExpand);
}
// TODO: change to fully recursive method
});
}
});
return buttons;
};
// currently displayed context menu, a singleton. We may only have one visible context menu
ContextMenu.visibleMenu = undefined;
/**
* Attach the menu to an anchor
* @param {HTMLElement} anchor Anchor where the menu will be attached
* as sibling.
* @param {HTMLElement} [contentWindow] The DIV with with the (scrollable) contents
*/
ContextMenu.prototype.show = function (anchor, contentWindow) {
this.hide();
// determine whether to display the menu below or above the anchor
var showBelow = true;
if (contentWindow) {
var anchorRect = anchor.getBoundingClientRect();
var contentRect = contentWindow.getBoundingClientRect();
if (anchorRect.bottom + this.maxHeight < contentRect.bottom) {
// fits below -> show below
}
else if (anchorRect.top - this.maxHeight > contentRect.top) {
// fits above -> show above
showBelow = false;
}
else {
// doesn't fit above nor below -> show below
}
}
// position the menu
if (showBelow) {
// display the menu below the anchor
var anchorHeight = anchor.offsetHeight;
this.dom.menu.style.left = '0px';
this.dom.menu.style.top = anchorHeight + 'px';
this.dom.menu.style.bottom = '';
}
else {
// display the menu above the anchor
this.dom.menu.style.left = '0px';
this.dom.menu.style.top = '';
this.dom.menu.style.bottom = '0px';
}
// attach the menu to the parent of the anchor
var parent = anchor.parentNode;
parent.insertBefore(this.dom.root, parent.firstChild);
// create and attach event listeners
var me = this;
var list = this.dom.list;
this.eventListeners.mousedown = util.addEventListener(window, 'mousedown', function (event) {
// hide menu on click outside of the menu
var target = event.target;
if ((target != list) && !me._isChildOf(target, list)) {
me.hide();
event.stopPropagation();
event.preventDefault();
}
});
this.eventListeners.keydown = util.addEventListener(window, 'keydown', function (event) {
me._onKeyDown(event);
});
// move focus to the first button in the context menu
this.selection = util.getSelection();
this.anchor = anchor;
setTimeout(function () {
me.dom.focusButton.focus();
}, 0);
if (ContextMenu.visibleMenu) {
ContextMenu.visibleMenu.hide();
}
ContextMenu.visibleMenu = this;
};
/**
* Hide the context menu if visible
*/
ContextMenu.prototype.hide = function () {
// remove the menu from the DOM
if (this.dom.root.parentNode) {
this.dom.root.parentNode.removeChild(this.dom.root);
if (this.onClose) {
this.onClose();
}
}
// remove all event listeners
// all event listeners are supposed to be attached to document.
for (var name in this.eventListeners) {
if (this.eventListeners.hasOwnProperty(name)) {
var fn = this.eventListeners[name];
if (fn) {
util.removeEventListener(window, name, fn);
}
delete this.eventListeners[name];
}
}
if (ContextMenu.visibleMenu == this) {
ContextMenu.visibleMenu = undefined;
}
};
/**
* Expand a submenu
* Any currently expanded submenu will be hided.
* @param {Object} domItem
* @private
*/
ContextMenu.prototype._onExpandItem = function (domItem) {
var me = this;
var alreadyVisible = (domItem == this.expandedItem);
// hide the currently visible submenu
var expandedItem = this.expandedItem;
if (expandedItem) {
//var ul = expandedItem.ul;
expandedItem.ul.style.height = '0';
expandedItem.ul.style.padding = '';
setTimeout(function () {
if (me.expandedItem != expandedItem) {
expandedItem.ul.style.display = '';
util.removeClassName(expandedItem.ul.parentNode, 'jsoneditor-selected');
}
}, 300); // timeout duration must match the css transition duration
this.expandedItem = undefined;
}
if (!alreadyVisible) {
var ul = domItem.ul;
ul.style.display = 'block';
var height = ul.clientHeight; // force a reflow in Firefox
setTimeout(function () {
if (me.expandedItem == domItem) {
ul.style.height = (ul.childNodes.length * 24) + 'px';
ul.style.padding = '5px 10px';
}
}, 0);
util.addClassName(ul.parentNode, 'jsoneditor-selected');
this.expandedItem = domItem;
}
};
/**
* Handle onkeydown event
* @param {Event} event
* @private
*/
ContextMenu.prototype._onKeyDown = function (event) {
var target = event.target;
var keynum = event.which;
var handled = false;
var buttons, targetIndex, prevButton, nextButton;
if (keynum == 27) { // ESC
// hide the menu on ESC key
// restore previous selection and focus
if (this.selection) {
util.setSelection(this.selection);
}
if (this.anchor) {
this.anchor.focus();
}
this.hide();
handled = true;
}
else if (keynum == 9) { // Tab
if (!event.shiftKey) { // Tab
buttons = this._getVisibleButtons();
targetIndex = buttons.indexOf(target);
if (targetIndex == buttons.length - 1) {
// move to first button
buttons[0].focus();
handled = true;
}
}
else { // Shift+Tab
buttons = this._getVisibleButtons();
targetIndex = buttons.indexOf(target);
if (targetIndex == 0) {
// move to last button
buttons[buttons.length - 1].focus();
handled = true;
}
}
}
else if (keynum == 37) { // Arrow Left
if (target.className == 'jsoneditor-expand') {
buttons = this._getVisibleButtons();
targetIndex = buttons.indexOf(target);
prevButton = buttons[targetIndex - 1];
if (prevButton) {
prevButton.focus();
}
}
handled = true;
}
else if (keynum == 38) { // Arrow Up
buttons = this._getVisibleButtons();
targetIndex = buttons.indexOf(target);
prevButton = buttons[targetIndex - 1];
if (prevButton && prevButton.className == 'jsoneditor-expand') {
// skip expand button
prevButton = buttons[targetIndex - 2];
}
if (!prevButton) {
// move to last button
prevButton = buttons[buttons.length - 1];
}
if (prevButton) {
prevButton.focus();
}
handled = true;
}
else if (keynum == 39) { // Arrow Right
buttons = this._getVisibleButtons();
targetIndex = buttons.indexOf(target);
nextButton = buttons[targetIndex + 1];
if (nextButton && nextButton.className == 'jsoneditor-expand') {
nextButton.focus();
}
handled = true;
}
else if (keynum == 40) { // Arrow Down
buttons = this._getVisibleButtons();
targetIndex = buttons.indexOf(target);
nextButton = buttons[targetIndex + 1];
if (nextButton && nextButton.className == 'jsoneditor-expand') {
// skip expand button
nextButton = buttons[targetIndex + 2];
}
if (!nextButton) {
// move to first button
nextButton = buttons[0];
}
if (nextButton) {
nextButton.focus();
handled = true;
}
handled = true;
}
// TODO: arrow left and right
if (handled) {
event.stopPropagation();
event.preventDefault();
}
};
/**
* Test if an element is a child of a parent element.
* @param {Element} child
* @param {Element} parent
* @return {boolean} isChild
*/
ContextMenu.prototype._isChildOf = function (child, parent) {
var e = child.parentNode;
while (e) {
if (e == parent) {
return true;
}
e = e.parentNode;
}
return false;
};
module.exports = ContextMenu;