I'm doing around 1-2 notifications a day and it's important the user doesn't miss it. Is there a way of removing the auto close and only allowing the user to manually close the notification?

I don's see any option for this in the Notification Options:

http://developer.chrome.com/extensions/notifications.html#type-NotificationOptions

回答1:

Notification now has (since Chrome 50) a requireInteraction property to force the notification to stay on screen:

var notification = new Notification("TITLE", {
          icon: 'assets/res/icon.png',
          body: "MESSAGE",
          requireInteraction: true     
});

In onclick you have to close the notification:

notification.onclick = function()
{
    this.close();
}

回答2:

UPDATE (2016-05-24):

Xan commented:

Fun fact: all this arcane hacking is no longer needed; see the new requireInteraction flag

It is availalbe since Chrome 50. More info.

_{Thanks to root's comment, this answer is revised to account for the fact that the onClosed event is not fired when the notification disappears (into the notigications area) after a few seconds. This is still kind of a hacky solution.}

Background

You can take advantage of the fact that a notification's life-cycle ends with one of the following events:

onClosed: When the user clicks on the small 'x' in the top-right corner.
onClicked: When the user clicks on the message body (not the 'x', not some button).
onButtonClicked: When the user clicks on one of the buttons (if any).

The solution

The proposed solution consists of the following steps:

Register listeners for all the events mentioned above.
Register a timeout after a few seconds (e.g. 30) -after the notification is hidden- that will delete and re-create the notification (so it effectively stays visible on the screen.
If any of the listeners set on step 1 fires, it means the user interracted with the notification, so cancel the timeout (you don't need to re-create the notification).

Writing about it is simple, coding takes some more effort :) Here is the sample code I used to achieve what is described above:

In manifest.json:

{
    "manifest_version": 2,
    "name":    "Test Extension",
    "version": "0.0",

    "background": {
        // We need this for the `Timeout` - see notes below
        "persistent": true,
        "scripts": ["background.js"]
    },

    "browser_action": {
        "default_title": "Test Extension"
        "default_icon": {
            "19": "img/icon19.png",
            "38": "img/icon38.png"
        },
    },

    "permissions": ["notifications"]
}

In background.js:

var pendingNotifications = {};

/* For demonstration purposes, the notification creation
 * is attached to the browser-action's `onClicked` event.
 * Change according to your needs. */
chrome.browserAction.onClicked.addListener(function() {
    var dateStr = new Date().toUTCString();
    var details = {
        type:    "basic",
        iconUrl: "/img/notifIcon.png",
        title:   "REMINDER",
        message: dateStr + "\n\n"
                 + "There is one very important matter to attend to !\n"
                 + "Deal with it now ?",
        contextMessage: "Very important stuff...",
        buttons: [
            { title: "Yes" }, 
            { title: "No"  }
        ]
    };
    var listeners = {
        onButtonClicked: function(btnIdx) {
            if (btnIdx === 0) {
                console.log(dateStr + ' - Clicked: "yes"');
            } else if (btnIdx === 1) {
                console.log(dateStr + ' - Clicked: "no"');
            }
        },
        onClicked: function() {
            console.log(dateStr + ' - Clicked: "message-body"');
        },
        onClosed: function(byUser) {
            console.log(dateStr + ' - Closed: '
                        + (byUser ? 'by user' : 'automagically (!?)'));
        }
    };

    /* Create the notification */
    createNotification(details, listeners);
});

/* Create a notification and store references
 * of its "re-spawn" timer and event-listeners */
function createNotification(details, listeners, notifId) {
    (notifId !== undefined) || (notifId = "");
    chrome.notifications.create(notifId, details, function(id) {
        console.log('Created notification "' + id + '" !');
        if (pendingNotifications[id] !== undefined) {
            clearTimeout(pendingNotifications[id].timer);
        }

        pendingNotifications[id] = {
            listeners: listeners,
            timer: setTimeout(function() {
                console.log('Re-spawning notification "' + id + '"...');
                destroyNotification(id, function(wasCleared) {
                    if (wasCleared) {
                        createNotification(details, listeners, id);
                    }
                });
            }, 10000)
        };
    });
}

/* Completely remove a notification, cancelling its "re-spawn" timer (if any)
 * Optionally, supply it with a callback to execute upon successful removal */
function destroyNotification(notifId, callback) {

    /* Cancel the "re-spawn" timer (if any) */
    if (pendingNotifications[notifId] !== undefined) {
        clearTimeout(pendingNotifications[notifId].timer);
        delete(pendingNotifications[notifId]);
    }

    /* Remove the notification itself */
    chrome.notifications.clear(notifId, function(wasCleared) {
        console.log('Destroyed notification "' + notifId + '" !');

        /* Execute the callback (if any) */
        callback && callback(wasCleared);
    });
}

/* Respond to the user's clicking one of the buttons */
chrome.notifications.onButtonClicked.addListener(function(notifId, btnIdx) {
    if (pendingNotifications[notifId] !== undefined) {
        var handler = pendingNotifications[notifId].listeners.onButtonClicked;
        destroyNotification(notifId, handler(btnIdx));
    }
});

/* Respond to the user's clicking on the notification message-body */
chrome.notifications.onClicked.addListener(function(notifId) {
    if (pendingNotifications[notifId] !== undefined) {
        var handler = pendingNotifications[notifId].listeners.onClicked;
        destroyNotification(notifId, handler());
    }
});

/* Respond to the user's clicking on the small 'x' in the top right corner */
chrome.notifications.onClosed.addListener(function(notifId, byUser) {
    if (pendingNotifications[notifId] !== undefined) {
        var handler = pendingNotifications[notifId].listeners.onClosed;
        destroyNotification(notifId, handler(byUser));
    }
});

_{Final notes:}

_{If your notifications are extremely important, you should implement a "recovery" mechanism, for case such as browser os OS crashes or abrupt termination. E.g. relying on a more persistent storage (localStorage, chrome.storage API etc), resuming pending notifications on extension/browser start-up etc.}
_{It might be a good idea to put a limit on the total number of pending notifications, for "user-friendliness" reasons. If your pending notifications exceed, say, 3 at any given moment, you could replace them with one that informs there are pending notifications and direct the user to a page where you list all of them. (The code will be considerably more complex, but hey anything for the user, right ? ;)}
_{Instead of trying to keep the notifications visible on screen until the user decides to deal with them, it could be better using a Badge (wich can have a color and a small text - indicating the number of pending notifications.}
_{I haven't looked into it, but it might be possible (in which case it is advisable as well) to replace the Timeout's with the chrome.alarms API and then convert the background-page to non-persistent (a.k.a. event-page) which will make it more resource-friendly.}

回答3:

UPDATE answar: after Chrome 50, please add new attribute: [requireInteraction: true]!

don't use chrome.notifications.create

try to use var notification= new Notification("New mail from John Doe", { tag: 'msg1', requireInteraction: true});
will not to close.

if want to close=> notification.close();

ref: http://www.w3.org/TR/notifications/

https://developer.mozilla.org/en-US/docs/Web/API/notification/requireInteraction

回答4:

webkit notifications seem to be more persistent on the screen, althouth they have the opposite problem - how to hide them to sys tray.

http://developer.chrome.com/extensions/desktop_notifications.html

回答5:

This answer is obsolete; see this answer for an up to date solution involving requireInteraction flag (Chrome 50+).

There is a slightly better (but again, hacky) solution.

When you call update on a notification that changes its priority, and the priority is 0 or above, the notification will be re-shown and the timer for hiding it reset.

So, you can show a notification with a high priority, (say, 2) and then repeat this on an interval shorter than time to hide the notification:

chrome.notifications.update(id, {priority : 1}, function(wasUpdated) {
  if(wasUpdated) {
    chrome.notifications.update(id, {priority : 2}, function() {});
  } else {
    // Notification was fully closed; either stop updating or create a new one
  }
});