NativeScript/nativescript-core/ui/list-picker/index.ios.ts

import {
	ListPickerBase,
	selectedIndexProperty,
	itemsProperty,
	ItemsSource,
} from "./list-picker-common";
import { Color } from "../../color";
import {
	backgroundColorProperty,
	colorProperty,
} from "../styling/style-properties";
import { profile } from "../../profiling";

export * from "./list-picker-common";

export class ListPicker extends ListPickerBase {
	nativeViewProtected: UIPickerView;
	// tslint:disable-next-line
	private _dataSource: ListPickerDataSource;
	private _delegate: ListPickerDelegateImpl;

	createNativeView() {
		return UIPickerView.new();
	}

	initNativeView() {
		super.initNativeView();
		const nativeView = this.nativeViewProtected;
		nativeView.dataSource = this._dataSource = ListPickerDataSource.initWithOwner(
			new WeakRef(this)
		);
		this._delegate = ListPickerDelegateImpl.initWithOwner(
			new WeakRef(this)
		);
	}

	public disposeNativeView() {
		this._dataSource = null;
		this._delegate = null;
		super.disposeNativeView();
	}

	get ios() {
		return this.nativeViewProtected;
	}

	@profile()
	public onLoaded() {
		super.onLoaded();
		this.ios.delegate = this._delegate;
	}

	public onUnloaded() {
		this.ios.delegate = null;
		super.onUnloaded();
	}

	[selectedIndexProperty.getDefault](): number {
		return -1;
	}
	[selectedIndexProperty.setNative](value: number) {
		if (value >= 0) {
			this.ios.selectRowInComponentAnimated(value, 0, false);
		}
	}

	[itemsProperty.getDefault](): any[] {
		return null;
	}
	[itemsProperty.setNative](value: any[] | ItemsSource) {
		this.ios.reloadAllComponents();

		// Coerce selected index after we have set items to native view.
		selectedIndexProperty.coerce(this);
	}

	[backgroundColorProperty.getDefault](): UIColor {
		return this.ios.backgroundColor;
	}
	[backgroundColorProperty.setNative](value: UIColor | Color) {
		this.ios.backgroundColor = value instanceof Color ? value.ios : value;
	}

	[colorProperty.getDefault](): UIColor {
		return this.ios.tintColor;
	}
	[colorProperty.setNative](value: UIColor | Color) {
		this.ios.tintColor = value instanceof Color ? value.ios : value;
	}
}

class ListPickerDataSource extends NSObject implements UIPickerViewDataSource {
	public static ObjCProtocols = [UIPickerViewDataSource];

	private _owner: WeakRef<ListPicker>;

	public static initWithOwner(
		owner: WeakRef<ListPicker>
	): ListPickerDataSource {
		let dataSource = <ListPickerDataSource>ListPickerDataSource.new();
		dataSource._owner = owner;

		return dataSource;
	}

	public numberOfComponentsInPickerView(pickerView: UIPickerView) {
		return 1;
	}

	public pickerViewNumberOfRowsInComponent(
		pickerView: UIPickerView,
		component: number
	) {
		let owner = this._owner.get();

		return owner && owner.items ? owner.items.length : 0;
	}
}

class ListPickerDelegateImpl extends NSObject implements UIPickerViewDelegate {
	public static ObjCProtocols = [UIPickerViewDelegate];

	private _owner: WeakRef<ListPicker>;

	public static initWithOwner(
		owner: WeakRef<ListPicker>
	): ListPickerDelegateImpl {
		let delegate = <ListPickerDelegateImpl>ListPickerDelegateImpl.new();
		delegate._owner = owner;

		return delegate;
	}

	public pickerViewAttributedTitleForRowForComponent(
		pickerView: UIPickerView,
		row: number,
		component: number
	): NSAttributedString {
		let owner = this._owner.get();
		if (owner) {
			let title = NSAttributedString.alloc().initWithStringAttributes(
				owner._getItemAsString(row),
				<any>{ [NSForegroundColorAttributeName]: pickerView.tintColor }
			);

			return title;
		}

		return NSAttributedString.alloc().initWithStringAttributes(
			row.toString(),
			<any>{ [NSForegroundColorAttributeName]: pickerView.tintColor }
		);
	}

	public pickerViewDidSelectRowInComponent(
		pickerView: UIPickerView,
		row: number,
		component: number
	): void {
		let owner = this._owner.get();
		if (owner) {
			selectedIndexProperty.nativeValueChange(owner, row);
			owner.updateSelectedValue(row);
		}
	}
}