angular2
Version:
Angular 2 - a web framework for modern web apps
194 lines • 7.55 kB
JavaScript
var __decorate = (this && this.__decorate) || function (decorators, target, key, desc) {
if (typeof Reflect === "object" && typeof Reflect.decorate === "function") return Reflect.decorate(decorators, target, key, desc);
switch (arguments.length) {
case 2: return decorators.reduceRight(function(o, d) { return (d && d(o)) || o; }, target);
case 3: return decorators.reduceRight(function(o, d) { return (d && d(target, key)), void 0; }, void 0);
case 4: return decorators.reduceRight(function(o, d) { return (d && d(target, key, o)) || o; }, desc);
}
};
var __metadata = (this && this.__metadata) || function (k, v) {
if (typeof Reflect === "object" && typeof Reflect.metadata === "function") return Reflect.metadata(k, v);
};
var __param = (this && this.__param) || function (paramIndex, decorator) {
return function (target, key) { decorator(target, key, paramIndex); }
};
import { Directive } from 'angular2/src/core/metadata';
import { Host } from 'angular2/src/core/di';
import { ViewContainerRef, TemplateRef } from 'angular2/src/core/linker';
import { isPresent, isBlank, normalizeBlank, CONST_EXPR } from 'angular2/src/facade/lang';
import { ListWrapper, Map } from 'angular2/src/facade/collection';
const _WHEN_DEFAULT = CONST_EXPR(new Object());
export class SwitchView {
constructor(_viewContainerRef, _templateRef) {
this._viewContainerRef = _viewContainerRef;
this._templateRef = _templateRef;
}
create() { this._viewContainerRef.createEmbeddedView(this._templateRef); }
destroy() { this._viewContainerRef.clear(); }
}
/**
* The `NgSwitch` directive is used to conditionally swap DOM structure on your template based on a
* scope expression.
* Elements within `NgSwitch` but without `NgSwitchWhen` or `NgSwitchDefault` directives will be
* preserved at the location as specified in the template.
*
* `NgSwitch` simply chooses nested elements and makes them visible based on which element matches
* the value obtained from the evaluated expression. In other words, you define a container element
* (where you place the directive), place an expression on the **`[ng-switch]="..."` attribute**),
* define any inner elements inside of the directive and place a `[ng-switch-when]` attribute per
* element.
* The when attribute is used to inform NgSwitch which element to display when the expression is
* evaluated. If a matching expression is not found via a when attribute then an element with the
* default attribute is displayed.
*
* ### Example
*
* ```
* <ANY [ng-switch]="expression">
* <template [ng-switch-when]="whenExpression1">...</template>
* <template [ng-switch-when]="whenExpression1">...</template>
* <template ng-switch-default>...</template>
* </ANY>
* ```
*/
export let NgSwitch = class {
constructor() {
this._useDefault = false;
this._valueViews = new Map();
this._activeViews = [];
}
set ngSwitch(value) {
// Empty the currently active ViewContainers
this._emptyAllActiveViews();
// Add the ViewContainers matching the value (with a fallback to default)
this._useDefault = false;
var views = this._valueViews.get(value);
if (isBlank(views)) {
this._useDefault = true;
views = normalizeBlank(this._valueViews.get(_WHEN_DEFAULT));
}
this._activateViews(views);
this._switchValue = value;
}
/** @internal */
_onWhenValueChanged(oldWhen, newWhen, view) {
this._deregisterView(oldWhen, view);
this._registerView(newWhen, view);
if (oldWhen === this._switchValue) {
view.destroy();
ListWrapper.remove(this._activeViews, view);
}
else if (newWhen === this._switchValue) {
if (this._useDefault) {
this._useDefault = false;
this._emptyAllActiveViews();
}
view.create();
this._activeViews.push(view);
}
// Switch to default when there is no more active ViewContainers
if (this._activeViews.length === 0 && !this._useDefault) {
this._useDefault = true;
this._activateViews(this._valueViews.get(_WHEN_DEFAULT));
}
}
/** @internal */
_emptyAllActiveViews() {
var activeContainers = this._activeViews;
for (var i = 0; i < activeContainers.length; i++) {
activeContainers[i].destroy();
}
this._activeViews = [];
}
/** @internal */
_activateViews(views) {
// TODO(vicb): assert(this._activeViews.length === 0);
if (isPresent(views)) {
for (var i = 0; i < views.length; i++) {
views[i].create();
}
this._activeViews = views;
}
}
/** @internal */
_registerView(value, view) {
var views = this._valueViews.get(value);
if (isBlank(views)) {
views = [];
this._valueViews.set(value, views);
}
views.push(view);
}
/** @internal */
_deregisterView(value, view) {
// `_WHEN_DEFAULT` is used a marker for non-registered whens
if (value === _WHEN_DEFAULT)
return;
var views = this._valueViews.get(value);
if (views.length == 1) {
this._valueViews.delete(value);
}
else {
ListWrapper.remove(views, view);
}
}
};
NgSwitch = __decorate([
Directive({ selector: '[ng-switch]', inputs: ['ngSwitch'] }),
__metadata('design:paramtypes', [])
], NgSwitch);
/**
* Defines a case statement as an expression.
*
* If multiple `NgSwitchWhen` match the `NgSwitch` value, all of them are displayed.
*
* Example:
*
* ```
* // match against a context variable
* <template [ng-switch-when]="contextVariable">...</template>
*
* // match against a constant string
* <template ng-switch-when="stringValue">...</template>
* ```
*/
export let NgSwitchWhen = class {
constructor(viewContainer, templateRef, _switch) {
this._switch = _switch;
// `_WHEN_DEFAULT` is used as a marker for a not yet initialized value
/** @internal */
this._value = _WHEN_DEFAULT;
this._view = new SwitchView(viewContainer, templateRef);
}
set ngSwitchWhen(value) {
this._switch._onWhenValueChanged(this._value, value, this._view);
this._value = value;
}
};
NgSwitchWhen = __decorate([
Directive({ selector: '[ng-switch-when]', inputs: ['ngSwitchWhen'] }),
__param(2, Host()),
__metadata('design:paramtypes', [ViewContainerRef, TemplateRef, NgSwitch])
], NgSwitchWhen);
/**
* Defines a default case statement.
*
* Default case statements are displayed when no `NgSwitchWhen` match the `ng-switch` value.
*
* Example:
*
* ```
* <template ng-switch-default>...</template>
* ```
*/
export let NgSwitchDefault = class {
constructor(viewContainer, templateRef, sswitch) {
sswitch._registerView(_WHEN_DEFAULT, new SwitchView(viewContainer, templateRef));
}
};
NgSwitchDefault = __decorate([
Directive({ selector: '[ng-switch-default]' }),
__param(2, Host()),
__metadata('design:paramtypes', [ViewContainerRef, TemplateRef, NgSwitch])
], NgSwitchDefault);
//# sourceMappingURL=ng_switch.js.map