zulip/zephyr/static/js/hashchange.js

91 lines
2.5 KiB
JavaScript

var hashchange = (function () {
var exports = {};
var expected_hash = false;
exports.changehash = function (newhash) {
expected_hash = newhash;
// Some browsers reset scrollTop when changing the hash to "",
// so we save and restore it.
// http://stackoverflow.com/questions/4715073/window-location-hash-prevent-scrolling-to-the-top
var scrolltop;
if (newhash === "") {
scrolltop = viewport.scrollTop();
}
window.location.hash = newhash;
util.reset_favicon();
if (newhash === "") {
viewport.scrollTop(scrolltop);
}
};
exports.save_narrow = function (operators) {
if (operators === undefined) {
exports.changehash('#');
} else {
var new_hash = '#narrow';
$.each(operators, function (idx, elem) {
new_hash += '/' + encodeURIComponent(elem[0])
+ '/' + encodeURIComponent(elem[1]);
});
exports.changehash(new_hash);
}
};
function parse_narrow(hash) {
var i, operators = [];
for (i=1; i<hash.length; i+=2) {
// We don't construct URLs with an odd number of components,
// but the user might write one.
var operator = decodeURIComponent(hash[i]);
var operand = decodeURIComponent(hash[i+1] || '');
operators.push([operator, operand]);
}
narrow.activate(operators);
}
// Returns true if this function performed a narrow
function hashchanged() {
// If window.location.hash changed because our app explicitly
// changed it, then we don't need to do anything.
// (This function only neds to jump into action if it changed
// because e.g. the back button was pressed by the user)
if (window.location.hash === expected_hash) {
return false;
}
var hash = window.location.hash.split("/");
switch (hash[0]) {
case "#narrow":
ui.change_tab_to("#home");
parse_narrow(hash);
ui.update_floating_recipient_bar();
return true;
case "":
case "#":
ui.change_tab_to("#home");
narrow.deactivate();
ui.update_floating_recipient_bar();
break;
case "#subscriptions":
ui.change_tab_to("#subscriptions");
break;
case "#settings":
ui.change_tab_to("#settings");
break;
}
return false;
}
exports.initialize = function () {
window.onhashchange = hashchanged;
if (hashchanged()) {
load_more_messages();
}
};
return exports;
}());