Angular2/Typescript - Parent/Child Directive(?)
I'm new to, and very much still learning, Angular2/Typescript/javascript. As a result, I'm not entirely sure how to title my question. The basis of my app is a card game. The premise (relative to my struggle) is that the game has 2 players and each player has a hand of 5 cards. I have API calls to build/return the hand of cards.
In my app.component template, I have 2 div blocks; one for each players' hand of cards. Currently, I have it working by building two distinct arrays of cards (named p1cards and p2cards). Here is the relative code for that:
<div class="player1Cards" id="player1Cards">
<ul class="list-group">
<div draggable *ngFor="let card of p1cards" [dragData]="card"
class="list-group-item">
<img src="{{cardBluePath + card.fileName}}">
</div>
</ul>
</div>
<div class="player2Cards" id="player2Cards">
<ul class="list-group">
<div draggable *ngFor="let card of p2cards" [dragData]="card"
class="list-group-item">
<img src="{{cardBluePath + card.fileName}}">
</div>
</ul>
</div>
And here is the actual export class of the entire AppComponent:
@Injectable()
export class AppComponent implements OnInit
{
@ViewChild(ModalComponent) errorMsg: ModalComponent;
errorMessage: string;
gameBoard: GameBoard[];
name: {};
mode = 'Observable';
//we need a gameboard (maybe not)
//we need an array of players
player:Player;
players:Player[] = [];
p1cards:Card[] = [];
p2cards:Card[] = [];
droppedItems = [];
//This tells us where the card images can be found
cardBluePath = "/assets/deck/Blue/";
cardRedPath = "/assets/deck/Red/";
//The boardService will handle our API calls
boardService;
//Initialize the API service
constructor(boardService:BoardService) {
this.boardService = boardService;
}
//On load...
ngOnInit()
{
//Create the game
this.boardService.createGame()
.subscribe(
error => this.errorMessage = <any>error);
//Create the players
this.createPlayer(0);
this.createPlayer(1);
}
createPlayer(player: number)
{
var playerName;
if (player == 0) {playerName = "Player1"} else {playerName = "Player2"};
//We'll make a call to the API to build the hand of cards
this.boardService.buildHand(player)
.subscribe(
cardList =>
{
var cardData = [];
cardData = JSON.parse(cardList.toString());
var i, itemLength, card
itemLength = cardData.length;
for(i=0;i<itemLength;i++)
{
let card = new Card();
Object.assign(card,
{
"cardNum":i,
"id": cardData[i].id,
"displayName": cardData[i].displayName,
"fileName": cardData[i].fileName,
"left": cardData[i].left,
"top": cardData[i].top,
"right": cardData[i].right,
"bottom": cardData[i].bottom,
"level": cardData[i].level,
"native": cardData[i].native
});
if (player == 0) {this.p1cards.push(card)} else {this.p2cards.push(card)};
////this.cards.push(card);
}
//Now we will create the player and feed it the hand
this.player = new Player(playerName);
if (player ==0) {this.player.cardHand = this.p1cards} else {this.player.cardHand = this.p2cards};
this.players.push(this.player);
}
);
}
//When a card is dropped...
onItemDrop(e: any, slot: any)
{
e.dragData.slot = slot;
//Update the object
this.boardService.playCard(slot, e.dragData.card)
.subscribe(result => {
//If the slot is open and the card is played, physically move the item
if (result == "true" )
{
this.droppedItems.push(e.dragData);
this.removeItem(e.dragData, this.p1cards);
}
else{
window.alert("Slot already occupied.");
//this.modalWindow.show()
//this.errorMsg.showErrorMessage("Slot already occupied.");
//this.errorMsg.show();
}
});
}
//Remove the card from the hand
removeItem(item: any, list: Array<any>)
{
let index = list.map((e) => {
return e.cardNum
}).indexOf(item.cardNum);
list.splice(index, 1);
}
}
The createPlayer function is really where the question begins. Currently, it will make the API call and parse the JSON back into an array of cards. Right now, the array of cards lives locally in the AppComponent (as p1cards or p2cards).
What I want to do instead is create a player objects (component) for each player, assign their respective hand of cards, and then put those players in an array. I had that part working (pieces of the code still exist above, but not all of it), but I hit a wall in my *ngFor to display the cards. In pseudocode, I understood what I needed to do, but in practice I couldn't figure it out.
I knew that div class player1Cards needed to be something like "let player of Players where name = player1", and then I needed to iterate over the player.cardHand[] array to display each of the cards. I tried quite a few things, but nothing worked.
So then, after a few hours of Google searching, I came to the conclusion that I needed a child view for the player to handle it. I currently have the following for that:
My player.html is:
<div draggable *ngFor="let card of cardHand" [dragData]="card" class="list-group-item">
<img src="{{cardBluePath + card.fileName}}">
</div>
And my player.ts is:
import { Component, Input, OnInit } from '@angular/core';
import { Card } from './card';
@Component({
selector: 'player',
templateUrl: './player.html',
})
export class Player implements OnInit
{
public cardHand: Card[];
cardBluePath = "/assets/deck/Blue/";
constructor
(
public name: string
)
{}
ngOnInit()
{
}
}
Then in my AppComponent template, I added the block (and Imported the player.ts)
I get an error message on App.Component "inline template:69:16 caused by: No provider for String!". Of all the Google research I performed and all of the changes I tried (ViewChild, Input/Output, Reference), I could not get it to work. I don't recall exactly what I did, but at one point I was able to eliminate the error, but the card array was not getting passed to the player (I wish I had committed or stashed that code).
In my mind, I understand the task at hand, I just can't make it happen. I know I need to create the Player object and feed it the respective cardHand in order for the player html to be able to parse it. I can do that fine in AppComponent, but once I try to do it as a parent/child, I get stuck.
Can someone help get me going in the right direction?