98 lines
2.6 KiB
TypeScript
98 lines
2.6 KiB
TypeScript
// #docregion
|
|
// #docregion lc-imports
|
|
import {
|
|
OnChanges, SimpleChange,
|
|
OnInit,
|
|
// DoCheck, // not demonstrated
|
|
AfterContentInit,
|
|
AfterContentChecked,
|
|
AfterViewInit,
|
|
AfterViewChecked,
|
|
OnDestroy
|
|
} from 'angular2/core';
|
|
// #docregion lc-imports
|
|
import {Component, Input, Output} from 'angular2/core';
|
|
import {LoggerService} from './logger.service';
|
|
|
|
let nextId = 1;
|
|
|
|
@Component({
|
|
selector: 'peek-a-boo',
|
|
template: '<p>Now you see my hero, {{name}}</p>',
|
|
styles: ['p {background: LightYellow; padding: 8px}']
|
|
})
|
|
// Don't HAVE to mention the Lifecycle Hook interfaces
|
|
// unless we want typing and tool support.
|
|
export class PeekABooComponent
|
|
implements OnChanges, OnInit,AfterContentInit,AfterContentChecked,
|
|
AfterViewInit, AfterViewChecked, OnDestroy {
|
|
@Input() name:string;
|
|
|
|
private _afterContentCheckedCounter = 1;
|
|
private _afterViewCheckedCounter = 1;
|
|
private _id = nextId++;
|
|
private _logger:LoggerService;
|
|
private _onChangesCounter = 1;
|
|
private _verb = 'initialized';
|
|
|
|
constructor(logger:LoggerService){
|
|
this._logger = logger;
|
|
}
|
|
|
|
// only called if there is an @input variable set by parent.
|
|
ngOnChanges(changes: {[propertyName: string]: SimpleChange}){
|
|
let changesMsgs:string[] = []
|
|
for (let propName in changes) {
|
|
if (propName === 'name') {
|
|
let name = changes['name'].currentValue;
|
|
changesMsgs.push(`name ${this._verb} to "${name}"`);
|
|
} else {
|
|
changesMsgs.push(propName + ' ' + this._verb);
|
|
}
|
|
}
|
|
this._logIt(`onChanges (${this._onChangesCounter++}): ${changesMsgs.join('; ')}`);
|
|
this._verb = 'changed'; // next time it will be a change
|
|
}
|
|
|
|
ngOnInit() {
|
|
this._logIt(`onInit`);
|
|
}
|
|
|
|
ngAfterContentInit(){
|
|
this._logIt(`afterContentInit`);
|
|
}
|
|
|
|
// Called after every change detection check
|
|
// of the component (directive) CONTENT
|
|
// Beware! Called frequently!
|
|
ngAfterContentChecked(){
|
|
let counter = this._afterContentCheckedCounter++;
|
|
let msg = `afterContentChecked (${counter})`;
|
|
this._logIt(msg);
|
|
}
|
|
|
|
ngAfterViewInit(){
|
|
this._logIt(`afterViewInit`);
|
|
}
|
|
|
|
// Called after every change detection check
|
|
// of the component (directive) VIEW
|
|
// Beware! Called frequently!
|
|
|
|
ngAfterViewChecked(){
|
|
let counter = this._afterViewCheckedCounter++;
|
|
let msg = `afterViewChecked (${counter})`;
|
|
this._logIt(msg);
|
|
}
|
|
|
|
ngOnDestroy() {
|
|
this._logIt(`onDestroy`);
|
|
}
|
|
|
|
private _logIt(msg:string){
|
|
// Don't tick or else
|
|
// the AfterContentChecked and AfterViewChecked recurse.
|
|
// Let parent call tick()
|
|
this._logger.log(`#${this._id } ${msg}`, true);
|
|
}
|
|
} |