Ionic serve Unhandled Promise Rejection Warning


#1

Dear ionic community,

I write this post because I have this problem a lot of times and I don’t know what cause these. I am running “ionic serve” for debug my project whithout any compiled error, but with this warning:

_UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): TypeError: Cannot read property 'content' of null_

when my project is open in my webbrowser the page is blank and the console output is:

Failed to load resource: the server responded with a status of 404 (Not Found)
2http://localhost:8100/build/main.js Failed to load resource: the server responded with a status of 404 (Not Found)
http://localhost:8100/build/main.css Failed to load resource: the server responded with a status of 404 (Not Found)

The point is in this function:

  loadChannels(data){
    this.appParam.sqlChannels =[];
    data.forEach(element => {
                  this.appParam.sqlChannels.push(new Channel(element.ID, element.ChanName, "localhost"));
        }); 
           
  }

If i comment the line “this.appParam.sqlChannels.push(new Channel(element.ID, element.ChanName, "localhost"));” it is solve.

This happen to me other times with variables declaration such as “new [class]()” or with the declaration of a simple variable with "var a =1".

Could you tell me why is happening that??

thanks in advance


#2

Sounds like some build error is resulting in the application not being built. There is probably something informative in the console.


#3

I checked ionic console and chrome console, and just appear what I wrote:

Ionic console, compiles perfectly with the follow warning:

> _UnhandledPromiseRejectionWarning: Unhandled promise rejection (rejection id: 1): TypeError: Cannot read property 'content' of null_

Ionic launch a blank page with the following error in chrome console:

Failed to load resource: the server responded with a status of 404 (Not Found)

Any other place where I could check?


#4

Same here, after I updated Ionic
Console:

[12:10:34]  sass: node_modules/ionic-angular/themes/ionic.functions.scss, line: 109 
            The map color `grey` is not defined. Please make sure the color exists in your `$colors` map. For example: 
            $colors: ( grey: #327eff ); 
 L109:    @error $error-msg;

[12:10:34] sass failed

Chrome Console:

Failed to load resource: main.css the server responded with a status of 404 (Not Found)


#5

Solve

I solved it. The problem was a circular reference between my models classes.


#6

how to do that ? can u explain in more ?