Look code.

```
import {Component} from 'angular2/core';
import {App} from 'client/project/project.app';
import {ProjectService} from 'service/project.service';

@Component({
    selector: 'project-info',
    templateUrl: 'client/project/info/project-info.html'
})
export class ProjectInfoComponent {
    project:IProject;

    constructor(
        private app: App,
        private projectService: ProjectService
    ){         
      this.project = this.app.selectedProject;
    }
}

```

I change this.app.selectedProject={...} in other component, I would like to this component rerender. How to do it? Invented only if using EventEmitter.

```
this.app.selectedProject.subscribe(project => {
 this.project = project;
});

```