classafReflux::ProgressDialogue

(Widget) - A dialogue window that displays an updatable progress bar.

Sample usage:

dialogue := ProgressDialogue()

dialogue.with {
    it.title = "Look at me!"
    it.image = Image(`fan://icons/x48/flux.png`)
    it.closeWhenFinished = false
}

result := dialogue.open(reflux.window) |ProgressWorker worker->Obj?| {
    worker.update(1, 4, "Processing...")
    Actor.sleep(2sec)

    worker.update(2, 4, "A Very Long...")
    Actor.sleep(2sec)

    worker.update(3, 4, "Process...")
    Actor.sleep(2sec)

    worker.update(4, 4, "Done.")
    return "result!"
}

Processing

As seen in the example, the work should be performed in the callback func passed to open(). The work func should then make repeated calls to ProgressWorker.update() to update the dialogue and progress bar.

The callback func is processed in its own thread. This keeps the UI thread free to update the progress dialogue as needed.

Note that this means the worker function should be immutatble.

To update other UI components from within the callback func, use Desktop:

registry := this.registry
Desktop.callAsync |->| {
    reflux := (Reflux) registry.serviceById(Reflux#.qname)
    reflux.refresh
    ...
}  

Cancelling

A user may cancel any progress dialogue at any time. Callback funcs should check the status of the ProgressWorker.cancelled flag and return early if set. An alternative is to call ProgressWorker.update() often, which throws a sys::CancelledErr if the cancelled flag has been set.

Should a progress dialogue be cancelled, ProgressDialogue.onCancel() is called. This hook may be overridden to perform custom cancel handling. By default the dialogue shows a Cancelled by User message.

To mimic a user pressing Cancel the callback func may simply throw a sys::CancelledErr.

Error Handling

Should an error occur, ProgressDialogue.onError(Err) is called. This hook may be overridden to perform custom cancel handling. By default the dialogue shows an error message and displays the stack trace in the details panel.

If the ProgressDialogue is autobuilt then the error is added to the Errors service.

dialogue := (ProgressDialogue) registry.autobuild(ProgressDialogue#)

or the dialogue may be set as an IoC field:

@Autobuild ProgressDialogue dialogue