NativeScript/tns-core-modules/ui/list-picker/list-picker.ios.ts

import { ListPickerBase, Color, selectedIndexProperty, itemsProperty, backgroundColorProperty, colorProperty } from "./list-picker-common";
import { ItemsSource } from ".";
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);
        }
    }
}