Sakurai/pdf.js
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Utilize async/await in PDFViewerApplication.load to reduce the number of Promises and temporary variables necessary when setting the initial document location

Browse Source
This commit is contained in:
Jonas Jenwald 2018-08-09 15:15:41 +02:00
parent 3eba7ea267
commit 1bdfdd07b8
1 changed files with 14 additions and 28 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

42
web/app.js
View File

@ -942,10 +942,6 @@ let PDFViewerApplication = {
} }
} }
let initialParams = {
bookmark: null,
hash: null,
};
let storePromise = store.getMultiple({ let storePromise = store.getMultiple({
page: null, page: null,
zoom: DEFAULT_SCALE_VALUE, zoom: DEFAULT_SCALE_VALUE,
@ -957,8 +953,10 @@ let PDFViewerApplication = {
spreadMode: null, spreadMode: null,
}).catch(() => { /* Unable to read from storage; ignoring errors. */ }); }).catch(() => { /* Unable to read from storage; ignoring errors. */ });
Promise.all([storePromise, pageModePromise]).then( Promise.all([
([values = {}, pageMode]) => { storePromise, pageModePromise,
]).then(async ([values = {}, pageMode]) => {
const initialBookmark = this.initialBookmark;
// Initialize the default values, from user preferences. // Initialize the default values, from user preferences.
const zoom = AppOptions.get('defaultZoomValue'); const zoom = AppOptions.get('defaultZoomValue');
let hash = zoom ? `zoom=${zoom}` : null; let hash = zoom ? `zoom=${zoom}` : null;
@ -981,52 +979,40 @@ let PDFViewerApplication = {
// Always let the user preference/history take precedence. // Always let the user preference/history take precedence.
sidebarView = sidebarView || apiPageModeToSidebarView(pageMode); sidebarView = sidebarView || apiPageModeToSidebarView(pageMode);
} }
return {
hash,
rotation,
sidebarView,
scrollMode,
spreadMode,
};
}).then(({ hash, rotation, sidebarView, scrollMode, spreadMode, }) => {
initialParams.bookmark = this.initialBookmark;
initialParams.hash = hash;
this.setInitialView(hash, { this.setInitialView(hash, {
rotation, sidebarView, scrollMode, spreadMode, rotation, sidebarView, scrollMode, spreadMode,
}); });
this.eventBus.dispatch('documentinit', { source: this, }); this.eventBus.dispatch('documentinit', { source: this, });
// Make all navigation keys work on document load, // Make all navigation keys work on document load,
// unless the viewer is embedded in a web page. // unless the viewer is embedded in a web page.
if (!this.isViewerEmbedded) { if (!this.isViewerEmbedded) {
pdfViewer.focus(); pdfViewer.focus();
} }
return Promise.race([ // For documents with different page sizes, once all pages are resolved,
// ensure that the correct location becomes visible on load.
// (To reduce the risk, in very large and/or slow loading documents,
// that the location changes *after* the user has started interacting
// with the viewer, wait for either `pagesPromise` or a timeout.)
await Promise.race([
pagesPromise, pagesPromise,
new Promise((resolve) => { new Promise((resolve) => {
setTimeout(resolve, FORCE_PAGES_LOADED_TIMEOUT); setTimeout(resolve, FORCE_PAGES_LOADED_TIMEOUT);
}), }),
]); ]);
}).then(() => { if (!initialBookmark && !hash) {
// For documents with different page sizes, once all pages are resolved,
// ensure that the correct location becomes visible on load.
// To reduce the risk, in very large and/or slow loading documents,
// that the location changes *after* the user has started interacting
// with the viewer, wait for either `pagesPromise` or a timeout above.
if (!initialParams.bookmark && !initialParams.hash) {
return; return;
} }
if (pdfViewer.hasEqualPageSizes) { if (pdfViewer.hasEqualPageSizes) {
return; return;
} }
this.initialBookmark = initialParams.bookmark; this.initialBookmark = initialBookmark;
// eslint-disable-next-line no-self-assign // eslint-disable-next-line no-self-assign
pdfViewer.currentScaleValue = pdfViewer.currentScaleValue; pdfViewer.currentScaleValue = pdfViewer.currentScaleValue;
this.setInitialView(initialParams.hash); // Re-apply the initial document location.
this.setInitialView(hash);
}).then(function() { }).then(function() {
// At this point, rendering of the initial page(s) should always have // At this point, rendering of the initial page(s) should always have
// started (and may even have completed). // started (and may even have completed).