3.1 KiB
Changes for v3
Events
In v3, there are 3 types of events:
- Application Events
- Window Events
- Custom Events
Application Events
Application events are events that are emitted by the application. These events include native events such as ApplicationDidFinishLaunching on macOS.
Window Events
Window events are events that are emitted by a window. These events include native events such as WindowDidBecomeMain on macOS.
Custom Events
Events that the user defines are called CustomEvents. This is to differentiate them from the Event object that is used to communicate with the browser. CustomEvents are now objects that encapsulate all the details of an event. This includes the event name, the data, and the source of the event.
The data associated with a CustomEvent is now a single value. If multiple values are required, then a struct can be used.
Event callbacks and Emit function signature
The signatures events callbacks (as used by On, Once & OnMultiple) have changed. In v2, the callback function received optional data. In v3, the callback function receives a CustomEvent object that contains all data related to the event.
Similarly, the Emit function has changed. Instead of taking a name and optional data, it now takes a single CustomEvent object that it will emit.
Off and OffAll
In v2, Off and OffAll calls would remove events in both JS and Go. Due to the multi-window nature of v3, this has been changed so that these methods only apply to the context they are called in. For example, if you call Off in a window, it will only remove events for that window. If you use Off in Go, it will only remove events for Go.
Logging
There was a lot of requests for different types of logging in v2 so for v3 we have simplified things to make it as customisable as you want. There is now a single call Log that takes a LogMessage object. This object contains the message, the level, and the source, the log message and any data to be printed out. The default logger is the Console logger, however any number of outputs to log to can be added. Simply add custom loggers to the options.Application.Logger.CustomLoggers slice. The default logger does not have log level filtering, however custom loggers can be added that do.
Developer notes
When emitting an event in Go, it will dispatch the event to local Go listeners and also each window in the application. When emitting an event in JS, it now sends the event to the application. This will be processed as if it was emitted in Go, however the sender ID will be that of the window.
Window
The Window API has largely remained the same, however there are a few changes to note.
- Windows now have a Name that identifies them. This is used to identify the window when emitting events.
ClipBoard
The clipboard API has been simplified. There is now a single Clipboard object that can be used to read and write to the clipboard. The Clipboard object is available in both Go and JS. SetText() to set the text and Text() to get the text.
Bindings
TBD
Dialogs
Dialogs are now available in JavaScript!