“loadURL” electron-Angular project only once Angular 编译器准备就绪

Question

In many electron-Angular tutorials you create the window and load index.html from localhost after a timeout. Typically, you'll find text like this:

// set timeout to render the window not until the Angular // compiler is ready to show the project

Now I think there must be a way to not just arbitrarily wait for ten seconds, but to have some kind of event to act upon.

Unfortunately, loadURL returns "true" even if the localhost is not yet reachable, so win.once('ready-to-show') is also called when, actually, it's not ready to show.

Ideally, I would like to have a loading screen until the Angular Compiler is ready. Any ideas? Thank you!

Answer 1

As I couldn't come up with an alternative I implemented this solution:

checkForLoad = setInterval(function () {
                if (!didLoad) {
                    win.webContents.reload();
                }
                else {
                    clearInterval(checkForLoad);
                    win.show();
                }
            }, 2000);

I reload the page every few seconds. In Angular, I just send and IPC Message to change "didLoad" to true once the Angular App is actually running. Works nicely, but obviously it would be better to have an event to act upon. In the meantime, it's close enough.

Answer 2

I found following solution:

In angular AppComponent in ngOnInit I call global method:

window.electron.appControl.isReady()

which call

isReady: () => ipcRenderer.send('appControl', AppControlEvents.IsReady),

and in electron main.ts I set flag for this event

ipcMain.on('appControl', (event, eventType) => {
  switch (eventType) {
    ...
    case AppControlEvents.IsReady:
       this.isReadyHandler();
       break;
  }
})

inside this handler we are sure that angular is loaded