Merge pull request #1579 from benubois/image_viewer

Use existing image for image viewer.
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Maurice Parker 2020-01-09 11:16:46 -08:00 committed by GitHub
commit 563b61c61b
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1 changed files with 115 additions and 91 deletions

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@ -1,109 +1,136 @@
var controller = new AbortController() var activeImageViewer = null;
// Cancel any pending image loads (there might be none) and reset the controller class ImageViewer {
function cancelImageLoad() { constructor(img) {
controller.abort(); this.img = img;
controller = new AbortController(); this.loadingInterval = null;
this.activityIndicator = "data:image/svg+xml;base64,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";
} }
// Used to pop a resizable image view isLoaded() {
async function imageWasClicked(img) { return this.img.classList.contains("nnwLoaded");
cancelImageLoad();
showNetworkLoading(img);
try {
const signal = controller.signal;
const response = await fetch(img.src, { signal: signal });
if (!response.ok) {
throw new Error('Network response was not ok.');
} }
const imgBlob = await response.blob(); clicked() {
if (signal.aborted) { this.showLoadingIndicator();
throw new Error('Network response was aborted.'); if (this.isLoaded()) {
this.showViewer();
} else {
var callback = () => {
if (this.isLoaded()) {
clearInterval(this.loadingInterval);
this.showViewer();
}
}
this.loadingInterval = setInterval(callback, 100);
}
} }
hideNetworkLoading(img); cancel() {
clearInterval(this.loadingInterval);
this.hideLoadingIndicator();
}
var reader = new FileReader(); showViewer() {
reader.readAsDataURL(imgBlob); this.hideLoadingIndicator();
reader.onloadend = function() {
img.classList.add("nnwClicked"); var canvas = document.createElement("canvas");
canvas.width = this.img.naturalWidth;
canvas.height = this.img.naturalHeight;
canvas.getContext("2d").drawImage(this.img, 0, 0);
const rect = img.getBoundingClientRect(); const rect = this.img.getBoundingClientRect();
var message = { const message = {
x: rect.x, x: rect.x,
y: rect.y, y: rect.y,
width: rect.width, width: rect.width,
height: rect.height height: rect.height,
imageURL: canvas.toDataURL(),
}; };
message.imageURL = reader.result;
var jsonMessage = JSON.stringify(message); var jsonMessage = JSON.stringify(message);
window.webkit.messageHandlers.imageWasClicked.postMessage(jsonMessage); window.webkit.messageHandlers.imageWasClicked.postMessage(jsonMessage);
} }
} catch (error) { hideImage() {
hideNetworkLoading(img); this.img.style.opacity = 0;
console.log('There has been a problem with your fetch operation: ', error.message);
} }
showImage() {
this.img.style.opacity = 1
window.webkit.messageHandlers.imageWasShown.postMessage("");
} }
function showNetworkLoading(img) { showLoadingIndicator() {
var wrapper = document.createElement("div"); var wrapper = document.createElement("div");
wrapper.classList.add("activityIndicatorWrap"); wrapper.classList.add("activityIndicatorWrap");
img.parentNode.insertBefore(wrapper, img); this.img.parentNode.insertBefore(wrapper, this.img);
wrapper.appendChild(img); wrapper.appendChild(this.img);
var activityIndicatorImg = document.createElement("img"); var activityIndicatorImg = document.createElement("img");
activityIndicatorImg.classList.add("activityIndicator"); activityIndicatorImg.classList.add("activityIndicator");
activityIndicatorImg.style.opacity = 0; activityIndicatorImg.style.opacity = 0;
activityIndicatorImg.src = activityIndicator; activityIndicatorImg.src = this.activityIndicator;
wrapper.appendChild(activityIndicatorImg); wrapper.appendChild(activityIndicatorImg);
// Wait a bit before showing the indicator
function showActivityIndicator() {
activityIndicatorImg.style.opacity = 1; activityIndicatorImg.style.opacity = 1;
} }
setTimeout(showActivityIndicator, 300);
}
function hideNetworkLoading(img) { hideLoadingIndicator() {
var wrapper = img.parentNode; var wrapper = this.img.parentNode;
if (wrapper.classList.contains("activityIndicatorWrap")) {
var wrapperParent = wrapper.parentNode; var wrapperParent = wrapper.parentNode;
wrapperParent.insertBefore(img, wrapper); wrapperParent.insertBefore(this.img, wrapper);
wrapperParent.removeChild(wrapper); wrapperParent.removeChild(wrapper);
} }
}
static init() {
cancelImageLoad();
// keep track of when an image has finished downloading for ImageViewer
document.querySelectorAll("img").forEach(element => {
element.onload = function() {
this.classList.add("nnwLoaded");
}
});
// Add the click listener for images
window.onclick = function(event) {
if (event.target.matches("img")) {
if (activeImageViewer && activeImageViewer.img === event.target) {
cancelImageLoad();
} else {
cancelImageLoad();
activeImageViewer = new ImageViewer(event.target);
activeImageViewer.clicked();
}
}
}
}
}
function cancelImageLoad() {
if (activeImageViewer) {
activeImageViewer.cancel();
activeImageViewer = null;
}
}
// Used to animate the transition to a fullscreen image
function hideClickedImage() { function hideClickedImage() {
var img = document.querySelector('.nnwClicked') if (activeImageViewer) {
img.style.opacity = 0 activeImageViewer.hideImage();
}
} }
// Used to animate the transition from a fullscreen image // Used to animate the transition from a fullscreen image
function showClickedImage() { function showClickedImage() {
var img = document.querySelector('.nnwClicked') if (activeImageViewer) {
img.classList.remove("nnwClicked"); activeImageViewer.showImage();
img.style.opacity = 1
window.webkit.messageHandlers.imageWasShown.postMessage("");
}
// Add the click listener for images
function imageClicks() {
window.onclick = function(event) {
if (event.target.matches('img')) {
imageWasClicked(event.target);
}
} }
} }
// Add the playsinline attribute to any HTML5 videos that don't have it. // Add the playsinline attribute to any HTML5 videos that don"t have it.
// Without this attribute videos may autoplay and take over the whole screen // Without this attribute videos may autoplay and take over the whole screen
// on an iphone when viewing an article. // on an iphone when viewing an article.
function inlineVideos() { function inlineVideos() {
@ -113,9 +140,6 @@ function inlineVideos() {
} }
function postRenderProcessing() { function postRenderProcessing() {
cancelImageLoad(); ImageViewer.init();
imageClicks();
inlineVideos(); inlineVideos();
} }
const activityIndicator = "data:image/svg+xml;base64,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";