zulip/static/js/message_scroll.js

90 lines
2.3 KiB
JavaScript

var message_scroll = (function () {
var exports = {};
var actively_scrolling = false;
var loading_more_messages_indicator_showing = false;
exports.show_loading_older = function () {
if (!loading_more_messages_indicator_showing) {
loading.make_indicator($('#loading_more_messages_indicator'),
{abs_positioned: true});
loading_more_messages_indicator_showing = true;
floating_recipient_bar.hide();
}
};
exports.hide_loading_older = function () {
if (loading_more_messages_indicator_showing) {
loading.destroy_indicator($("#loading_more_messages_indicator"));
loading_more_messages_indicator_showing = false;
}
};
exports.hide_indicators = function () {
exports.hide_loading_older();
};
exports.actively_scrolling = function () {
return actively_scrolling;
};
exports.scroll_finished = function () {
actively_scrolling = false;
if (!$('#home').hasClass('active')) {
return;
}
if (!pointer.suppress_scroll_pointer_update) {
message_viewport.keep_pointer_in_view();
} else {
pointer.set_suppress_scroll_pointer_update(false);
}
floating_recipient_bar.update();
if (message_viewport.at_top()) {
message_fetch.maybe_load_older_messages({
msg_list: current_msg_list,
show_loading: exports.show_loading_older,
hide_loading: exports.hide_loading_older,
});
}
if (message_viewport.at_bottom()) {
message_fetch.maybe_load_newer_messages({
msg_list: current_msg_list,
});
}
// When the window scrolls, it may cause some messages to
// enter the screen and become read. Calling
// unread_ops.process_visible will update necessary
// data structures and DOM elements.
setTimeout(unread_ops.process_visible, 0);
};
var scroll_timer;
function scroll_finish() {
actively_scrolling = true;
clearTimeout(scroll_timer);
scroll_timer = setTimeout(exports.scroll_finished, 100);
}
exports.initialize = function () {
message_viewport.message_pane.scroll(_.throttle(function () {
unread_ops.process_visible();
scroll_finish();
}, 50));
};
return exports;
}());
if (typeof module !== 'undefined') {
module.exports = message_scroll;
}
window.message_scroll = message_scroll;