Angular2: Can't resolve all parameters for my directive

Question

I'm writing a directive which has dependencies on TemplateRef<any> and ViewContainerRef. But my directive cannot get these dependencies injected in. The following are all my code:

main.ts

import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { AppModule } from './app.module';
platformBrowserDynamic().bootstrapModule(AppModule);

app.module.ts

import { NgModule }      from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { HelloWorld } from './HelloWorld.directive';

@NgModule({
    imports: [BrowserModule],
    declarations: [AppComponent, HelloWorld],
    bootstrap: [AppComponent]
})
export class AppModule { }

app.component.ts

import { Component } from '@angular/core';

@Component({
    selector: 'my-app',
    template: ` 
           Hello world!
           <template [lcngHw]="true"><div></div></template>
           `
})
export class AppComponent {
}

HelloWorld.directive.ts

import { Directive } from '@angular/core';
import { Input } from '@angular/core';

import { TemplateRef, ViewContainerRef } from '@angular/core';

@Directive({
    selector: '[lcngHw]'
})
export class HelloWorld{
    constructor(private tf: TemplateRef<any>, private vc: ViewContainerRef){

    }

    @Input()
    set lcngHw(value: boolean) {
        if (value) {
            this.vc.createEmbeddedView(this.tf);
        }
        else {
            this.vc.clear();
        }
    }
}

And here is my transpiled HelloWorld.directive.js:

"use strict";
var __decorate = (this && this.__decorate) || function (decorators, target, key, desc) {
    var c = arguments.length, r = c < 3 ? target : desc === null ? desc = Object.getOwnPropertyDescriptor(target, key) : desc, d;
    if (typeof Reflect === "object" && typeof Reflect.decorate === "function") r = Reflect.decorate(decorators, target, key, desc);
    else for (var i = decorators.length - 1; i >= 0; i--) if (d = decorators[i]) r = (c < 3 ? d(r) : c > 3 ? d(target, key, r) : d(target, key)) || r;
    return c > 3 && r && Object.defineProperty(target, key, r), r;
};
var core_1 = require('@angular/core');
var core_2 = require('@angular/core');
var HelloWorld = (function () {
    function HelloWorld(tf, vc) {
        this.tf = tf;
        this.vc = vc;
    }
    Object.defineProperty(HelloWorld.prototype, "lcngHw", {
        set: function (value) {
            if (value) {
                this.vc.createEmbeddedView(this.tf);
            }
            else {
                this.vc.clear();
            }
        },
        enumerable: true,
        configurable: true
    });
    __decorate([
        core_2.Input()
    ], HelloWorld.prototype, "lcngHw", null);
    HelloWorld = __decorate([
        core_1.Directive({
            selector: '[lcngHw]'
        })
    ], HelloWorld);
    return HelloWorld;
}());
exports.HelloWorld = HelloWorld;

Then I run my app, and I get the following error:

Error: (SystemJS) Can't resolve all parameters for HelloWorld: (?, ?).

Error: Can't resolve all parameters for HelloWorld: (?, ?). at CompileMetadataResolver.getDependenciesMetadata (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:14268:21) at CompileMetadataResolver.getTypeMetadata (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:14169:28) at CompileMetadataResolver.getDirectiveMetadata (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:13944:30) at eval (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:14037:51) at Array.forEach (native) at CompileMetadataResolver.getNgModuleMetadata (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:14031:51) at RuntimeCompiler._compileComponents (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:16721:49) at RuntimeCompiler._compileModuleAndComponents (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:16659:39) at RuntimeCompiler.compileModuleAsync (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:16650:23) at PlatformRef_._bootstrapModuleWithZone (http://localhost:5000/node_modules/@angular/core/bundles/core.umd.js:6707:29) Evaluating http://localhost:5000/ViewContainerRefApp/main.js Error loading http://localhost:5000/ViewContainerRefApp/main.js at CompileMetadataResolver.getDependenciesMetadata (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:14268:21) at CompileMetadataResolver.getTypeMetadata (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:14169:28) at CompileMetadataResolver.getDirectiveMetadata (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:13944:30) at eval (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:14037:51) at Array.forEach (native) at CompileMetadataResolver.getNgModuleMetadata (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:14031:51) at RuntimeCompiler._compileComponents (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:16721:49) at RuntimeCompiler._compileModuleAndComponents (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:16659:39) at RuntimeCompiler.compileModuleAsync (http://localhost:5000/node_modules/@angular/compiler/bundles/compiler.umd.js:16650:23) at PlatformRef_._bootstrapModuleWithZone (http://localhost:5000/node_modules/@angular/core/bundles/core.umd.js:6707:29) Evaluating http://localhost:5000/ViewContainerRefApp/main.js Error loading http://localhost:5000/ViewContainerRefApp/main.js

I also copied the code from this live sample and I got the same error.

It seems that TemplateRef<any> and ViewContainerRef's metadata are not registerd. But I cannot find out the reason. Anyone can help me? Thank you.

Answer 1

If you are using a tsconfig.json, add emitDecoratorMetaData: true

If you are using Visual Studio without a tsConfig.json add the TypeScriptEmitDecoratorMetadata tag to your project file Note: you will probably need more tags

<PropertyGroup Condition="'$(Configuration)' == 'Debug'">
    <TypeScriptRemoveComments>false</TypeScriptRemoveComments>
    <TypeScriptSourceMap>true</TypeScriptSourceMap>
    <TypeScriptTarget>ES5</TypeScriptTarget>
    <TypeScriptJSXEmit>None</TypeScriptJSXEmit>
    <TypeScriptCompileOnSaveEnabled>True</TypeScriptCompileOnSaveEnabled>
    <TypeScriptNoImplicitAny>False</TypeScriptNoImplicitAny>
    <TypeScriptModuleKind>System</TypeScriptModuleKind>
    <TypeScriptModuleResolution>node</TypeScriptModuleResolution>
    <TypeScriptOutFile />
    <TypeScriptOutDir />
    <TypeScriptGeneratesDeclarations>False</TypeScriptGeneratesDeclarations>
    <TypeScriptNoEmitOnError>True</TypeScriptNoEmitOnError>
    <TypeScriptMapRoot />
    <TypeScriptSourceRoot />
    <TypeScriptExperimentalDecorators>True</TypeScriptExperimentalDecorators>
    <TypeScriptEmitDecoratorMetadata>True</TypeScriptEmitDecoratorMetadata>
</PropertyGroup>

Answer 2

You have to use one of these options for structural directive:

<div *lcngHw="true"></div>

<template [lcngHw]="true"><div></div></template>

<div template="lcngHw true"></div>

This way you can inject TemplateRef in your component

Plunker Example

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