Tuesday, 25 July 2017

Windows 10 Notification

Here is a quick and simple example of a notification procedure. On a form I added a 'TNotificationCenter' component from the 'System' tool palette.

procedure TForm.DoNotification(aName, aTitle, aBody: string);
var
    appNotification: TNotification;
begin
    appNotification := NotificationCenter1.CreateNotification;
    try
        appNotification.Name := aName;
        appNotification.Title := aTitle;
        appNotification.AlertBody := aBody;
        NotificationCenter1.PresentNotification(appNotification);
    finally
        appNotification.Free;
    end;
end;

procedure TForm.ShowTestNotification;
begin
    DoNotification('Test Name', 'Test Title', 'This is an example');
end;

There is an event in the NotificationCenter component called 'OnReceiveLocalNotification', which is useful if you want to display a notification and when a user clicks on the notification the software performs an operation. 

I did this example in Delphi XE10 Berlin, it is a very limited example due to Delphi being very limited with what can be done with Windows Notifications. Looking at the documentation you can do more with iOS, I am not sure why they have made it so limited. I have briefly looked at some C# examples and you can do more with notifications like custom sounds, icons, images and actions. 

One thing I have noticed is that when I run this example the notification is shown and then when it goes away it is automatically removed from the action centre. One thing I would require is that if the user does not acknowledge the notification, it should stay in the Action Centre list. For me it would be really useful to have the following:
  • Custom image.
  • Custom sound.
  • FireDate to work in Windows 10.
  • Option for the notification to stay in the Action Centre.

I would like to see Embarcadero expand on what these notifications can do, obviously they are limited to what the OS can do. If they could persist in the Action Centre until clicked then I can think of multiple uses for notifications.  

Monday, 24 July 2017

XE10 Berlin fix for issue when opening older project

I recently had an issue with a project that had been updated from XE to XE10. The issue was when opening the project it could not find some components on the main form (3rd party), however the correct packages are installed and if I started a new project I could add the components from the tool palette without any issues.

One work-around I found was having adding these components to another project, then when I opened Delphi XE10 I opened this project and then closed it before opening the project that had problems with the components, and it all worked fine.

In the end the solution I found was the following:

  1. In the package itself, find the unit with the 'Register' procedure.
  2. Check 'DesignInf' is in the uses clause.
  3. At the top of the 'Register' procedure add 'ForceDemandLoadState(dlDisable);' 
  4. Install the package again.
What this does is disables the IDE from using the smart loading of installed packages, this means when the IDE starts it always loads the installed packages.

Thursday, 20 July 2017

How to create GUID at runtime

To create a GUID (Globally Unique Identifier) at runtime I have two different ways of doing this.

First Method
Add ComObj unit to the uses clause, if not already there, then to create the GUID as a string just do the following:
FThisID := CreateClassID;

Second Method
This method you need the SysUtils in the uses clause. The do something like the following:
var
  newGUID: TGUID;
begin
  SysUtils.CreateGUID(newGUID);
  FThisID := GUIDToString(newGUID); 
end;