Merge pull request #887 from avandecreme/eventsource

Add addOnceHandler method to EventSource.
This commit is contained in:
Ian Gilman 2016-03-24 09:24:54 -07:00
commit 24f552c1fb
2 changed files with 78 additions and 1 deletions

View File

@ -56,7 +56,31 @@ $.EventSource = function() {
/** @lends OpenSeadragon.EventSource.prototype */
$.EventSource.prototype = {
// TODO: Add a method 'one' which automatically unbinds a listener after the first triggered event that matches.
/**
* Add an event handler to be triggered only once (or a given number of times)
* for a given event.
* @function
* @param {String} eventName - Name of event to register.
* @param {OpenSeadragon.EventHandler} handler - Function to call when event
* is triggered.
* @param {Object} [userData=null] - Arbitrary object to be passed unchanged
* to the handler.
* @param {Number} [times=1] - The number of times to handle the event
* before removing it.
*/
addOnceHandler: function(eventName, handler, userData, times) {
var self = this;
times = times || 1;
var count = 0;
var onceHandler = function(event) {
count++;
if (count === times) {
self.removeHandler(eventName, onceHandler);
}
handler(event);
};
this.addHandler(eventName, onceHandler, userData);
},
/**
* Add an event handler for a given event.

View File

@ -949,6 +949,59 @@
viewer.open( '/test/data/testpattern.dzi' );
} );
// ----------
test('EventSource: addOnceHandler', function() {
var eventSource = new OpenSeadragon.EventSource();
var userData = 'data';
var eventData = {
foo: 1
};
var handlerCalledCount = 0;
eventSource.addOnceHandler('test-event', function(event) {
handlerCalledCount++;
strictEqual(event.foo, eventData.foo,
'Event data should be transmitted to the event.');
strictEqual(event.userData, userData,
'User data should be transmitted to the event.');
}, userData);
strictEqual(0, handlerCalledCount,
'Handler should not have been called yet.');
eventSource.raiseEvent('test-event', eventData);
strictEqual(1, handlerCalledCount,
'Handler should have been called once.');
eventSource.raiseEvent('test-event', eventData);
strictEqual(1, handlerCalledCount,
'Handler should still have been called once.');
});
// ----------
test('EventSource: addOnceHandler 2 times', function() {
var eventSource = new OpenSeadragon.EventSource();
var userData = 'data';
var eventData = {
foo: 1
};
var handlerCalledCount = 0;
eventSource.addOnceHandler('test-event', function(event) {
handlerCalledCount++;
strictEqual(event.foo, eventData.foo,
'Event data should be transmitted to the event.');
strictEqual(event.userData, userData,
'User data should be transmitted to the event.');
}, userData, 2);
strictEqual(0, handlerCalledCount,
'Handler should not have been called yet.');
eventSource.raiseEvent('test-event', eventData);
strictEqual(1, handlerCalledCount,
'Handler should have been called once.');
eventSource.raiseEvent('test-event', eventData);
strictEqual(2, handlerCalledCount,
'Handler should have been called twice.');
eventSource.raiseEvent('test-event', eventData);
strictEqual(2, handlerCalledCount,
'Handler should still have been called twice.');
});
// ----------
asyncTest( 'Viewer: tile-drawing event', function () {
var tileDrawing = function ( event ) {