在Typora中，預設沒有點選圖片放大功能，本文就教大家如何配置該功能。
我的環境版本
- Typora版本：0.11.13
- LightBox版本：2.11.3
下載LightBox
可以從Github下載：https://github.com/lokesh/lightbox2
拷貝檔案
將dist目錄中的檔案拷貝到Typora的安裝目錄的相應位置下。
在安裝目錄的D:\Program Files\Typora\resources\資料夾下，新建了extend資料夾，用來存放擴充套件外掛的，dist目錄下的檔案也放到了這。
修改window.html檔案
位置：D:\Program Files\Typora\resources\window.html（這個檔案實際就是Typora的主介面）
引入 css 檔案
可以搜尋</head>，在它的前面新增：
<link rel="stylesheet" href="./extend/lightbox2/css/lightbox.min.css" crossorigin="anonymous">
引入 js 檔案
可以搜尋</script><script src="./appsrc/window/frame.js" defer="defer"></script>，然後在它的後面新增：
< type="text/javascript" src="./extend/lightbox2/js/lightbox.js" defer="defer">
修改 lightbox.js 檔案
因為lightbox需要有 a 標籤包圍著 img 標籤，相應的點選事件是繫結在 a 標籤上的，且需要 href 、 data-lightbox 、 data-alt 等屬性，而Typora中的圖片只有 img 標籤，父級沒有 a 標籤，也沒有相應要求的屬性。因此需要改造一下 lightbox.js 檔案。
為img標籤繫結雙擊事件
修改enable函式，新增程式碼：
//為img繫結雙擊事件，但要排除本就是雙擊放大展示的圖片
$('body').on('dblclick', "img:not([class='lb-image'])" ,function(event){
self.start($(event.currentTarget));
return false;
});
修改屬性值獲取
lightbox用到三個屬性：alt、href 、title，這三個屬性在img標籤中均有對應的。
修改start函式，換成img對應屬性：
function addToAlbum($link) {
self.album.push({
alt: $link.attr('data-alt')|| $link.attr('alt'),
link: $link.attr('href')|| $link.attr('src'),
title: $link.attr('data-title') || $link.attr('title')
});
}
註釋data-lightbox
還有另外一個屬性data-lightbox，img沒有該屬性，因此這裡不使用，lightbox中有一段判斷是否有該屬性的程式碼，修改不存在該屬性時的邏輯程式碼（註釋掉原有的，新增addToAlbum($link);）：
修改完成，儲存即可。
想要省事也可以直接複製下面的程式碼替換掉lightbox.js中的所有程式碼
(function (root, factory) {
if (typeof define === 'function' && define.amd) {
// AMD. Register as an anonymous module.
define(['jquery'], factory);
} else if (typeof exports === 'object') {
// Node. Does not work with strict CommonJS, but
// only CommonJS-like environments that support module.exports,
// like Node.
module.exports = factory(require('jquery'));
} else {
// Browser globals (root is window)
root.lightbox = factory(root.jQuery);
}
}(this, function ($) {
function Lightbox(options) {
this.album = [];
this.currentImageIndex = void 0;
this.init();
// options
this.options = $.extend({}, this.constructor.defaults);
this.option(options);
}
// Descriptions of all options available on the demo site:
// http://lokeshdhakar.com/projects/lightbox2/index.html#options
Lightbox.defaults = {
albumLabel: 'Image %1 of %2',
alwaysShowNavOnTouchDevices: false,
fadeDuration: 0,
fitImagesInViewport: true,
imageFadeDuration: 0,
// maxWidth: 800,
// maxHeight: 10,
positionFromTop: 10,
resizeDuration: 0,
showImageNumberLabel: true,
wrapAround: false,
disableScrolling: false,
/*
Sanitize Title
If the caption data is trusted, for example you are hardcoding it in, then leave this to false.
This will free you to add html tags, such as links, in the caption.
If the caption data is user submitted or from some other untrusted source, then set this to true
to prevent xss and other injection attacks.
*/
sanitizeTitle: false
};
Lightbox.prototype.option = function(options) {
$.extend(this.options, options);
};
Lightbox.prototype.imageCountLabel = function(currentImageNum, totalImages) {
return this.options.albumLabel.replace(/%1/g, currentImageNum).replace(/%2/g, totalImages);
};
Lightbox.prototype.init = function() {
var self = this;
// Both enable and build methods require the body tag to be in the DOM.
$(document).ready(function() {
self.enable();
self.build();
});
};
// Loop through anchors and areamaps looking for either data-lightbox attributes or rel attributes
// that contain 'lightbox'. When these are clicked, start lightbox.
Lightbox.prototype.enable = function() {
var self = this;
$('body').on('click', 'a[rel^=lightbox], area[rel^=lightbox], a[data-lightbox], area[data-lightbox]', function(event) {
self.start($(event.currentTarget));
return false;
});
//為img繫結雙擊事件，但要排除本就是雙擊放大展示的圖片
$('body').on('dblclick', "img:not([class='lb-image'])", function(event) {
self.start($(event.currentTarget));
self.$image.css("zoom", "100%")
return false;
});
};
// Build html for the lightbox and the overlay.
// Attach event handlers to the new DOM elements. click click click
Lightbox.prototype.build = function() {
if ($('#lightbox').length > 0) {
// return;
}
var self = this;
// The two root notes generated, #lightboxOverlay and #lightbox are given
// tabindex attrs so they are focusable. We attach our keyboard event
// listeners to these two elements, and not the document. Clicking anywhere
// while Lightbox is opened will keep the focus on or inside one of these
// two elements.
//
// We do this so we can prevent propogation of the Esc keypress when
// Lightbox is open. This prevents it from intefering with other components
// on the page below.
//
// Github issue: https://github.com/lokesh/lightbox2/issues/663
$('<div id="lightboxOverlay" tabindex="-1" class="lightboxOverlay"></div><div id="lightbox" tabindex="-1" class="lightbox"><div class="lb-outerContainer" style="overflow:auto;"><div class="lb-container"><img class="lb-image" src="data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACH5BAEAAAAALAAAAAABAAEAAAICRAEAOw==" alt=""/><div class="lb-nav"><a class="lb-prev" aria-label="Previous image" href="" ></a><a class="lb-next" aria-label="Next image" href="" ></a></div><div class="lb-loader"><a class="lb-cancel"></a></div></div></div><div class="lb-dataContainer"><div class="lb-data"><div class="lb-details"><span class="lb-caption"></span><span class="lb-number"></span></div><div class="lb-closeContainer"><a class="lb-close"></a></div></div></div></div>').appendTo($('body'));
// Cache jQuery objects
this.$lightbox = $('#lightbox');
this.$overlay = $('#lightboxOverlay');
this.$outerContainer = this.$lightbox.find('.lb-outerContainer');
this.$container = this.$lightbox.find('.lb-container');
this.$image = this.$lightbox.find('.lb-image');
this.$nav = this.$lightbox.find('.lb-nav');
// Store css values for future lookup
this.containerPadding = {
top: parseInt(this.$container.css('padding-top'), 10),
right: parseInt(this.$container.css('padding-right'), 10),
bottom: parseInt(this.$container.css('padding-bottom'), 10),
left: parseInt(this.$container.css('padding-left'), 10)
};
this.imageBorderWidth = {
top: parseInt(this.$image.css('border-top-width'), 10),
right: parseInt(this.$image.css('border-right-width'), 10),
bottom: parseInt(this.$image.css('border-bottom-width'), 10),
left: parseInt(this.$image.css('border-left-width'), 10)
};
// Attach event handlers to the newly minted DOM elements
this.$overlay.hide().on('click', function() {
self.end();
return false;
});
this.$lightbox.hide().on('click', function(event) {
if ($(event.target).attr('id') === 'lightbox') {
self.end();
}
});
this.$outerContainer.on('click', function(event) {
if ($(event.target).attr('id') === 'lightbox') {
self.end();
}
return false;
});
this.$lightbox.find('.lb-prev').on('click', function() {
if (self.currentImageIndex === 0) {
self.changeImage(self.album.length - 1);
} else {
self.changeImage(self.currentImageIndex - 1);
}
return false;
});
this.$lightbox.find('.lb-next').on('click', function() {
if (self.currentImageIndex === self.album.length - 1) {
self.changeImage(0);
} else {
self.changeImage(self.currentImageIndex + 1);
}
return false;
});
/*
Show context menu for image on right-click
There is a div containing the navigation that spans the entire image and lives above of it. If
you right-click, you are right clicking this div and not the image. This prevents users from
saving the image or using other context menu actions with the image.
To fix this, when we detect the right mouse button is pressed down, but not yet clicked, we
set pointer-events to none on the nav div. This is so that the upcoming right-click event on
the next mouseup will bubble down to the image. Once the right-click/contextmenu event occurs
we set the pointer events back to auto for the nav div so it can capture hover and left-click
events as usual.
*/
this.$nav.on('mousedown', function(event) {
if (event.which === 3) {
self.$nav.css('pointer-events', 'none');
self.$lightbox.one('contextmenu', function() {
setTimeout(function() {
this.$nav.css('pointer-events', 'auto');
}.bind(self), 0);
});
}
});
//給放大的圖片另外繫結滾輪放大縮小事件
this.$container.on('mousewheel', function(event) {
event.delta = (event.originalEvent.wheelDelta) ? event.originalEvent.wheelDelta / 120 : -(event.originalEvent.detail || 0) / 3;
var zoom = self.$image.css("zoom")
zoom = zoom ? zoom * 100 : 100;
zoom += event.delta*10;
if(zoom > 0)
self.$image.css("zoom",zoom + "%")
console.log(self.$image.width(),self.$image.height())
imageWidth = self.$image.width()
imageHeight = self.$image.height()
imageWidth = imageWidth*zoom*0.01
imageHeight = imageHeight*zoom*0.01
self.sizeContainer(imageWidth, imageHeight);
return false;
});
//給放大的圖片另外繫結雙擊關閉事件
this.$container.on('dblclick', function(event) {
self.end();
return false;
});
this.$lightbox.find('.lb-loader, .lb-close').on('click', function() {
self.end();
return false;
});
};
// Show overlay and lightbox. If the image is part of a set, add siblings to album array.
Lightbox.prototype.start = function($link) {
var self = this;
var $window = $(window);
$window.on('resize', $.proxy(this.sizeOverlay, this));
this.sizeOverlay();
this.album = [];
var imageNumber = 0;
function addToAlbum($link) {
self.album.push({
alt: $link.attr('data-alt') || $link.attr('alt'),
link: $link.attr('href') || $link.attr('src'),
title: $link.attr('data-title') || $link.attr('title')
});
}
// Support both data-lightbox attribute and rel attribute implementations
var dataLightboxValue = $link.attr('data-lightbox');
var $links;
if (dataLightboxValue) {
$links = $($link.prop('tagName') + '[data-lightbox="' + dataLightboxValue + '"]');
for (var i = 0; i < $links.length; i = ++i) {
addToAlbum($($links[i]));
if ($links[i] === $link[0]) {
imageNumber = i;
}
}
} else {
/* if ($link.attr('rel') === 'lightbox') {
// If image is not part of a set
addToAlbum($link);
} else {
// If image is part of a set
$links = $($link.prop('tagName') + '[rel="' + $link.attr('rel') + '"]');
for (var j = 0; j < $links.length; j = ++j) {
addToAlbum($($links[j]));
if ($links[j] === $link[0]) {
imageNumber = j;
}
}
} */
addToAlbum($link);
}
// Position Lightbox
var top = $window.scrollTop() || 0 + this.options.positionFromTop;
var left = $window.scrollLeft();
this.$lightbox.css({
top: top + 'px',
left: left + 'px'
}).fadeIn(this.options.fadeDuration);
// Disable scrolling of the page while open
if (this.options.disableScrolling) {
$('body').addClass('lb-disable-scrolling');
}
this.changeImage(imageNumber);
};
// Hide most UI elements in preparation for the animated resizing of the lightbox.
Lightbox.prototype.changeImage = function(imageNumber) {
var self = this;
var filename = this.album[imageNumber].link;
var filetype = filename.split('.').slice(-1)[0];
var $image = this.$lightbox.find('.lb-image');
// Disable keyboard nav during transitions
this.disableKeyboardNav();
// Show loading state
this.$overlay.fadeIn(this.options.fadeDuration);
$('.lb-loader').fadeIn('slow');
this.$lightbox.find('.lb-image, .lb-nav, .lb-prev, .lb-next, .lb-dataContainer, .lb-numbers, .lb-caption').hide();
this.$outerContainer.addClass('animating');
// When image to show is preloaded, we send the width and height to sizeContainer()
var preloader = new Image();
preloader.onload = function() {
var $preloader;
var imageHeight;
var imageWidth;
var maxImageHeight;
var maxImageWidth;
var windowHeight;
var windowWidth;
$image.attr({
'alt': self.album[imageNumber].alt,
'src': filename
});
$preloader = $(preloader);
$image.width(preloader.width);
$image.height(preloader.height);
windowWidth = $(window).width();
windowHeight = $(window).height();
// Calculate the max image dimensions for the current viewport.
// Take into account the border around the image and an additional 10px gutter on each side.
maxImageWidth = windowWidth - self.containerPadding.left - self.containerPadding.right - self.imageBorderWidth.left - self.imageBorderWidth.right - 20;
maxImageHeight = windowHeight - self.containerPadding.top - self.containerPadding.bottom - self.imageBorderWidth.top - self.imageBorderWidth.bottom - self.options.positionFromTop - 70;
/*
Since many SVGs have small intrinsic dimensions, but they support scaling
up without quality loss because of their vector format, max out their
size.
*/
if (filetype === 'svg') {
$image.width(maxImageWidth);
$image.height(maxImageHeight);
}
// Fit image inside the viewport.
if (self.options.fitImagesInViewport) {
// Check if image size is larger then maxWidth|maxHeight in settings
if (self.options.maxWidth && self.options.maxWidth < maxImageWidth) {
maxImageWidth = self.options.maxWidth;
}
if (self.options.maxHeight && self.options.maxHeight < maxImageHeight) {
maxImageHeight = self.options.maxHeight;
}
} else {
maxImageWidth = self.options.maxWidth || preloader.width || maxImageWidth;
maxImageHeight = self.options.maxHeight || preloader.height || maxImageHeight;
}
// Is the current image's width or height is greater than the maxImageWidth or maxImageHeight
// option than we need to size down while maintaining the aspect ratio.
if ((preloader.width > maxImageWidth) || (preloader.height > maxImageHeight)) {
if ((preloader.width / maxImageWidth) > (preloader.height / maxImageHeight)) {
imageWidth = maxImageWidth;
imageHeight = parseInt(preloader.height / (preloader.width / imageWidth), 10);
$image.width(imageWidth);
$image.height(imageHeight);
} else {
imageHeight = maxImageHeight;
imageWidth = parseInt(preloader.width / (preloader.height / imageHeight), 10);
$image.width(imageWidth);
$image.height(imageHeight);
}
}
self.sizeContainer($image.width(), $image.height());
};
// Preload image before showing
preloader.src = this.album[imageNumber].link;
this.currentImageIndex = imageNumber;
};
// Stretch overlay to fit the viewport
Lightbox.prototype.sizeOverlay = function() {
var self = this;
/*
We use a setTimeout 0 to pause JS execution and let the rendering catch-up.
Why do this? If the `disableScrolling` option is set to true, a class is added to the body
tag that disables scrolling and hides the scrollbar. We want to make sure the scrollbar is
hidden before we measure the document width, as the presence of the scrollbar will affect the
number.
*/
setTimeout(function() {
self.$overlay
.width($(document).width())
.height($(document).height());
}, 0);
};
// Animate the size of the lightbox to fit the image we are showing
// This method also shows the the image.
Lightbox.prototype.sizeContainer = function(imageWidth, imageHeight) {
var self = this;
var oldWidth = this.$outerContainer.outerWidth();
var oldHeight = this.$outerContainer.outerHeight();
var newWidth = imageWidth + this.containerPadding.left + this.containerPadding.right + this.imageBorderWidth.left + this.imageBorderWidth.right;
var newHeight = imageHeight + this.containerPadding.top + this.containerPadding.bottom + this.imageBorderWidth.top + this.imageBorderWidth.bottom;
//最大不超過螢幕寬高，若超過，滾動條出現
windowWidth = $(window).width();
windowHeight = $(window).height();
if(newWidth > windowWidth){
newWidth = windowWidth
}
if(newHeight+self.$lightbox.find('.lb-dataContainer').height() > windowHeight){
newHeight = windowHeight - self.$lightbox.find('.lb-dataContainer').height()*2
}
function postResize() {
self.$lightbox.find('.lb-dataContainer').width(newWidth);
self.$lightbox.find('.lb-prevLink').height(newHeight);
self.$lightbox.find('.lb-nextLink').height(newHeight);
// Set focus on one of the two root nodes so keyboard events are captured.
self.$overlay.focus();
self.showImage();
}
if (oldWidth !== newWidth || oldHeight !== newHeight) {
this.$outerContainer.animate({
width: newWidth,
height: newHeight
}, this.options.resizeDuration, 'swing', function() {
postResize();
});
} else {
postResize();
}
};
// Display the image and its details and begin preload neighboring images.
Lightbox.prototype.showImage = function() {
this.$lightbox.find('.lb-loader').stop(true).hide();
this.$lightbox.find('.lb-image').fadeIn(this.options.imageFadeDuration);
this.updateNav();
this.updateDetails();
this.preloadNeighboringImages();
this.enableKeyboardNav();
};
// Display previous and next navigation if appropriate.
Lightbox.prototype.updateNav = function() {
// Check to see if the browser supports touch events. If so, we take the conservative approach
// and assume that mouse hover events are not supported and always show prev/next navigation
// arrows in image sets.
var alwaysShowNav = false;
try {
document.createEvent('TouchEvent');
alwaysShowNav = (this.options.alwaysShowNavOnTouchDevices) ? true : false;
} catch (e) {}
this.$lightbox.find('.lb-nav').show();
if (this.album.length > 1) {
if (this.options.wrapAround) {
if (alwaysShowNav) {
this.$lightbox.find('.lb-prev, .lb-next').css('opacity', '1');
}
this.$lightbox.find('.lb-prev, .lb-next').show();
} else {
if (this.currentImageIndex > 0) {
this.$lightbox.find('.lb-prev').show();
if (alwaysShowNav) {
this.$lightbox.find('.lb-prev').css('opacity', '1');
}
}
if (this.currentImageIndex < this.album.length - 1) {
this.$lightbox.find('.lb-next').show();
if (alwaysShowNav) {
this.$lightbox.find('.lb-next').css('opacity', '1');
}
}
}
}
};
// Display caption, image number, and closing button.
Lightbox.prototype.updateDetails = function() {
var self = this;
// Enable anchor clicks in the injected caption html.
// Thanks Nate Wright for the fix. @https://github.com/NateWr
if (typeof this.album[this.currentImageIndex].title !== 'undefined' &&
this.album[this.currentImageIndex].title !== '') {
var $caption = this.$lightbox.find('.lb-caption');
if (this.options.sanitizeTitle) {
$caption.text(this.album[this.currentImageIndex].title);
} else {
$caption.html(this.album[this.currentImageIndex].title);
}
$caption.fadeIn('fast');
}
if (this.album.length > 1 && this.options.showImageNumberLabel) {
var labelText = this.imageCountLabel(this.currentImageIndex + 1, this.album.length);
this.$lightbox.find('.lb-number').text(labelText).fadeIn('fast');
} else {
this.$lightbox.find('.lb-number').hide();
}
this.$outerContainer.removeClass('animating');
this.$lightbox.find('.lb-dataContainer').fadeIn(this.options.resizeDuration, function() {
return self.sizeOverlay();
});
};
// Preload previous and next images in set.
Lightbox.prototype.preloadNeighboringImages = function() {
if (this.album.length > this.currentImageIndex + 1) {
var preloadNext = new Image();
preloadNext.src = this.album[this.currentImageIndex + 1].link;
}
if (this.currentImageIndex > 0) {
var preloadPrev = new Image();
preloadPrev.src = this.album[this.currentImageIndex - 1].link;
}
};
Lightbox.prototype.enableKeyboardNav = function() {
this.$lightbox.on('keyup.keyboard', $.proxy(this.keyboardAction, this));
this.$overlay.on('keyup.keyboard', $.proxy(this.keyboardAction, this));
};
Lightbox.prototype.disableKeyboardNav = function() {
this.$lightbox.off('.keyboard');
this.$overlay.off('.keyboard');
};
Lightbox.prototype.keyboardAction = function(event) {
var KEYCODE_ESC = 27;
var KEYCODE_LEFTARROW = 37;
var KEYCODE_RIGHTARROW = 39;
var keycode = event.keyCode;
if (keycode === KEYCODE_ESC) {
// Prevent bubbling so as to not affect other components on the page.
event.stopPropagation();
this.end();
} else if (keycode === KEYCODE_LEFTARROW) {
if (this.currentImageIndex !== 0) {
this.changeImage(this.currentImageIndex - 1);
} else if (this.options.wrapAround && this.album.length > 1) {
this.changeImage(this.album.length - 1);
}
} else if (keycode === KEYCODE_RIGHTARROW) {
if (this.currentImageIndex !== this.album.length - 1) {
this.changeImage(this.currentImageIndex + 1);
} else if (this.options.wrapAround && this.album.length > 1) {
this.changeImage(0);
}
}
};
// Closing time. :-(
Lightbox.prototype.end = function() {
this.disableKeyboardNav();
$(window).off('resize', this.sizeOverlay);
this.$lightbox.fadeOut(this.options.fadeDuration);
this.$overlay.fadeOut(this.options.fadeDuration);
if (this.options.disableScrolling) {
$('body').removeClass('lb-disable-scrolling');
}
};
return new Lightbox();
}));
啟動Typora，驗證
雙擊要放到檢視的圖片，即可。