Skip to main content

5 Cool Things you can do with HTML5 (p4)

By
The fourth part of this series of posts will cover Notifications. When you are a user of GMail and using Chrome, you probably are familiar with those little boxes that popup when you've got new mail. Those type of notifications you can create in your APEX application as well - using HTML5!
Alas, at this moment, these type of notifications only work in Chrome. In Firefox you can add this extension so it'll work in that browser as well. The other ones will follow - sooner or later...
You can also use this plugin that mimics this feature - to be safe on every platform, but that one will appear in your browser, so that's not a desktop notification.
But how do you create a real desktop notification?
As usual with HTML5, you just need a few lines of code. The code below is executed in a Dynamic Action when a button is pressed:

function RequestPermission (callback) {
window.webkitNotifications.requestPermission(callback);
}
function showNotification(){
if (window.webkitNotifications){
  if (window.webkitNotifications.checkPermission() > 0) {
  RequestPermission(showNotification);
  }
  else {
  window.webkitNotifications.createNotification(
  "#APP_IMAGES#HTML5.jpg", //Put link to your icon here
  "Notification",
  "Now you are notified!").show();
  }
 }
else
{ alert('Sorry, you have to switch to another browser to use notifications - or use the other button ;-)');
}
}
//Run:
showNotification();


Just like geoLocations, the browser has to ask the user for permission to use Desktop Notifications (for a domain). Once the permission has been granted you can call the "show()" method, containing an image, the title and the actual message. Easy and cool, huh!

And you can even get completely wild by creating notifications that contain HTML or adding event listeners to your notifications - for instance doing something when the notification is closed. See this for some more examples.

See the working APEX example on : http://apex.oracle.com/pls/apex/f?p=22115:NOTIFICATIONS.
Labels:

Comments

fateh.cis said…
Hello,
Can you please, make your app available for us to download for better understanding ...

Another thing, on the link you referenced - for more examples - there is plus sign on the right hand that we can use to scroll down to specific section on the page. How can we apply this on APEX to scroll down into specific region on the page..

Best Regards,
Fateh
6:24 am
fateh.cis said…
Thanks a lot for making your examples app available for us...
Can we use this notification to send a notification to a specific apex user ??

Best Regards,
Fateh
1:20 pm
Roel said…
@Fateh: Using some creativity, you can...
Imagine you create a table with a TO_USER and MESSAGE column. Then you can conditionally load a region containing with the notification on Page 0 - so when the user refreshes or changes the page he gets the notification.
If you want to send a user a notification even without a refresh/pagechange, you should check out Websockets....

HTH
Roel
7:30 pm
Post a Comment

Popular posts from this blog

Filtering in the APEX Interactive Grid

By
Remember Oracle Forms? One of the nice features of Forms was the use of GLOBAL items. More or less comparable to Application Items in APEX. These GLOBALS where often used to pre-query data. For example you queried Employee 200 in Form A, then opened Form B and on opening that Form the Employee field is filled with that (GLOBAL) value of 200 and the query was executed. So without additional keys strokes or entering data, when switching to another Form a user would immediately see the data in the same context. And they loved that. In APEX you can create a similar experience using Application Items (or an Item on the Global Page) for Classic Reports (by setting a Default Value to a Search Item) and Interactive Reports (using the  APEX_IR.ADD_FILTER  procedure). But what about the Interactive Grid? There is no APEX_IG package ... so the first thing we have to figure out is how can we set a filter programmatically? Start with creating an Interactive Grid based upon the good old Employ
1 comment
Read more

apex_application.g_f0x array processing in Oracle 12

By
If you created your own "updatable reports" or your custom version of tabular forms in Oracle Application Express, you'll end up with a query that looks similar to this one: then you disable the " Escape special characters " property and the result is an updatable multirecord form. That was easy, right? But now we need to process the changes in the Ename column when the form is submitted, but only if the checkbox is checked. All the columns are submitted as separated arrays, named apex_application.g_f0x - where the "x" is the value of the "p_idx" parameter you specified in the apex_item calls. So we have apex_application.g_f01, g_f02 and g_f03. But then you discover APEX has the oddity that the "checkbox" array only contains values for the checked rows. Thus if you just check "Jones", the length of g_f02 is 1 and it contains only the empno of Jones - while the other two arrays will contain all (14) rows. So for
Post a Comment
Read more

Stop using validations for checking constraints !

By
 If you run your APEX application - like a Form based on the EMP table - and test if you can change the value of Department to something else then the standard values of 10, 20, 30 or 40, you'll get a nice error message like this: But it isn't really nice, is it? So what do a lot of developers do? They create a validation (just) in order to show a nicer, better worded, error message like "This is not a valid department".  And what you then just did is writing code twice : Once in the database as a (foreign key) check constraint and once as a sql statement in your validation. And we all know : writing code twice is usually not a good idea - and executing the same query twice is not enhancing your performance! So how can we transform that ugly error message into something nice? By combining two APEX features: the Error Handling Function and the Text Messages! Start with copying the example of an Error Handling Function from the APEX documentation. Create this function
Post a Comment
Read more