import {Directive, ElementRef, Renderer, Optional, EventEmitter, Input, Output, HostListener, ContentChildren, QueryList} from 'angular2/core';
import {NgControl} from 'angular2/common';
import {isDefined} from '../../util/util';
/**
* @name SegmentButton
* @description
* The child buttons of the `ion-segment` component. Each `ion-segment-button` must have a value.
* @property {string} [value] - the value of the segment-button. Required.
* @usage
* ```html
*
*
* Friends
*
*
* Enemies
*
*
*```
*
* Or with `FormBuilder`
*
*```html
*
* ```
*
* @property {Any} [click] - expression to evaluate when a segment button has been clicked
*
* @demo /docs/v2/demos/segment/
* @see {@link /docs/v2/components#segment Segment Component Docs}
* @see {@link /docs/v2/api/components/segment/Segment/ Segment API Docs}
*/
@Directive({
selector: 'ion-segment-button',
host: {
'tappable': '',
'class': 'segment-button',
'role': 'button'
}
})
export class SegmentButton {
@Input() value: string;
@Output() select: EventEmitter = new EventEmitter();
constructor(private _renderer: Renderer, private _elementRef: ElementRef) {}
/**
* @private
* On click of a SegmentButton
*/
@HostListener('click', ['$event'])
private onClick(ev) {
console.debug('SegmentButton, select', this.value);
this.select.emit(this);
}
ngOnInit() {
if (!isDefined(this.value)) {
console.warn(' requires a "value" attribute');
}
}
public set isActive(isActive) {
this._renderer.setElementClass(this._elementRef, 'segment-activated', isActive);
this._renderer.setElementAttribute(this._elementRef, 'aria-pressed', isActive);
}
}
/**
* @name Segment
* @description
* A Segment is a group of buttons, sometimes known as Segmented Controls, that allow the user to interact with a compact group of a number of controls.
* Segments provide functionality similar to tabs, selecting one will unselect all others. You should use a tab bar instead of a segmented control when you want to let the user move back and forth between distinct pages in your app.
* You could use Angular 2's `ngModel` or `FormBuilder` API. For an overview on how `FormBuilder` works, checkout [Angular 2 Forms](http://learnangular2.com/forms/), or [Angular FormBuilder](https://angular.io/docs/ts/latest/api/common/FormBuilder-class.html)
*
*
* @usage
* ```html
*
*
* Friends
*
*
* Enemies
*
*
*```
*
* Or with `FormBuilder`
*
*```html
*
* ```
*
* @property {Any} [change] - expression to evaluate when a segment button has been changed
*
* @demo /docs/v2/demos/segment/
* @see {@link /docs/v2/components#segment Segment Component Docs}
* @see [Angular 2 Forms](http://learnangular2.com/forms/)
*/
@Directive({
selector: 'ion-segment'
})
export class Segment {
value: string;
onChange = (_) => {};
onTouched = (_) => {};
@Output() change: EventEmitter = new EventEmitter();
@ContentChildren(SegmentButton) _buttons: QueryList;
constructor(@Optional() ngControl: NgControl) {
if (ngControl) {
ngControl.valueAccessor = this;
}
}
/**
* @private
* Write a new value to the element.
*/
writeValue(value) {
this.value = isDefined(value) ? value : '';
if (this._buttons) {
let buttons = this._buttons.toArray();
for (let button of buttons) {
button.isActive = (button.value === this.value);
}
}
}
/**
* @private
*/
ngAfterViewInit() {
let buttons = this._buttons.toArray();
for (let button of buttons) {
button.select.subscribe((selectedButton) => {
this.writeValue(selectedButton.value);
this.onChange(selectedButton.value);
this.change.emit(selectedButton);
});
if (isDefined(this.value)) {
button.isActive = (button.value === this.value);
}
}
}
/**
* @private
* Set the function to be called when the control receives a change event.
*/
registerOnChange(fn) { this.onChange = fn; }
/**
* @private
* Set the function to be called when the control receives a touch event.
*/
registerOnTouched(fn) { this.onTouched = fn; }
}