摘要：最近在項(xiàng)目重構(gòu)的過程中，發(fā)現(xiàn)之前用寫的地區(qū)選擇指令在中很難重用畢竟是用。但是此組件并不符合我的要求。我不是單純的選擇省市區(qū)，還可能是選擇省市或者省。

最近在項(xiàng)目重構(gòu)的過程中，發(fā)現(xiàn)之前用mobiscroll寫的地區(qū)選擇指令在angular2中很難重用（畢竟是用typeScript）。于是就萌生了自己寫一個(gè)組件的想法。
想和之前一樣基于mobiscroll去寫，但是發(fā)現(xiàn)非常耗費(fèi)精力，于是某日萬般無奈這下搜了一下相關(guān)的組件，不出所料已經(jīng)有人寫了。
https://www.npmjs.com/package...
但是此組件并不符合我的要求。
我不是單純的選擇省市區(qū)，還可能是選擇省市或者省。于是參照此項(xiàng)目基于ionic2的picker寫了一個(gè)公用組件。
具體代碼如下：
AreasSelect.ts

import {PickerController} from "ionic-angular";
import {Component, EventEmitter, Output, Input} from "@angular/core";
import {areasList} from "../../datasource/areas";

@Component({
    selector: "areas-select",
    templateUrl: "areasSelect.com.html",
})
export class AreasSelect {
    constructor(protected Picker: PickerController) {
    }
    private picker;
    private provinceCol = 0; // 省列
    private cityCol = 0; // 市列
    private regionCol = 0; // 區(qū)列
    private pickerColumnCmps; // picker縱列數(shù)據(jù)實(shí)例
    private isOpen = false; //  是否被創(chuàng)建
    private pickerCmp; // picker 實(shí)例
    private value = ""; // 選中后的數(shù)據(jù)
    @Input() citiesData = areasList;　// 地區(qū)數(shù)據(jù)(默認(rèn)為areas.ts的數(shù)據(jù))
    @Input() cancelText = "關(guān)閉"; // 關(guān)閉按鈕文本
    @Input() doneText = "完成"; // 完成按鈕文本
    @Input() separator = ""; // 數(shù)據(jù)銜接模式
    @Input() level = 3; // 等級(jí)設(shè)置 最高為三級(jí)
    /**
     *  關(guān)閉時(shí)觸發(fā)的事件
     *  沒有值返回
     * @type {EventEmitter}
     */
    @Output() cancel: EventEmitter = new EventEmitter(); // 關(guān)閉事件
    /**
     *  完成時(shí)觸發(fā)的事件
     *  返回值為obj
     *  obj = {data: object,value: string} data為對(duì)應(yīng)的省市區(qū)和編碼
     * @type {EventEmitter}
     */
    @Output() done: EventEmitter = new EventEmitter(); // 完成事件
    /**
     *  打開地區(qū)選擇器
     *  基本思路
     *  1.創(chuàng)建picker
     * 2. 先把數(shù)據(jù)處理成省市區(qū)分開的數(shù)組
     * 3. 將數(shù)據(jù)以列的形式給到picker
     * 4. 設(shè)置數(shù)據(jù)顯示樣式（picker）
     * 5. 生成picker
     */
    private open() {
        let pickerOptions = {
            buttons: [
                {
                    text: this.cancelText,
                    role: "cancel",
                    handler:() => {
                        this.cancel.emit(null);
                    }
                },
                {
                    text: this.doneText,
                    handler: (data) =>{
                        this.onChange(data);
                        this.done.emit({
                            data: data,
                            value: this.value
                        });
                    }
                }
            ]
        };
        this.picker = this.Picker.create(pickerOptions);
        this.generate();// 加載
        this.validate(this.picker); // 渲染
        this.picker.ionChange.subscribe(() => {
            this.validate(this.picker);
        });
        // 生成
        this.picker.present(pickerOptions).then(() => {
            this.pickerCmp = this.picker.instance;
            this.pickerColumnCmps = this.pickerCmp._cols.toArray();
            this.pickerColumnCmps.forEach(function (col) {
                return col.lastIndex = -1;
            });
        });
        this.isOpen = true;
        this.picker.onDidDismiss(function () {
            this.isOpen = false;
        });
    }

    /** 對(duì)數(shù)據(jù)進(jìn)行處理，并移交給picker
     *
     */
    private generate() {
        let values = this.value.toString().split(this.separator);
        // Add province data to picker
        let provinceCol = {
            name: "province",
            options: this.citiesData.map(function (province) {
                return {text: province.name, value: province.code, disabled: false};
            }),
            selectedIndex: 0
        };
        let provinceIndex = this.citiesData.findIndex(function (option) {
            return option.name == values[0];
        });
        provinceIndex = provinceIndex === -1 ? 0 : provinceIndex;
        provinceCol.selectedIndex = provinceIndex;
        this.picker.addColumn(provinceCol);
        // Add city data to picker
        let cityColData = this.citiesData[provinceCol.selectedIndex].children;
        let cityCol;

        if (this.level >= 2) {
            cityCol = {
                name: "city",
                options: cityColData.map(function (city) {
                    return {text: city.name, value: city.code, disabled: false};
                }),
                selectedIndex: 0
            };
            let cityIndex = cityColData.findIndex(function (option) {
                return option.name == values[1];
            });
            cityIndex = cityIndex === -1 ? 0 : cityIndex;
            cityCol.selectedIndex = cityIndex;
            this.picker.addColumn(cityCol);
        }
        // Add region data to picker
        let regionData, regionCol;

        if (this.level === 3) {
            regionData = this.citiesData[provinceCol.selectedIndex].children[cityCol.selectedIndex].children;
            regionCol = {
                name: "region",
                options: regionData.map(function (city) {
                    return {text: city.name, value: city.code, disabled: false};
                }),
                selectedIndex: 0
            };
            let regionIndex = regionData.findIndex(function (option) {
                return option.name == values[2];
            });
            regionIndex = regionIndex === -1 ? 0 : regionIndex;
            regionCol.selectedIndex = regionIndex;
            this.picker.addColumn(regionCol);
        }
        this.divyColumns(this.picker);
    }

    /**設(shè)置數(shù)據(jù)顯示樣式
     * @param picker
     */
    private divyColumns(picker) {
        let pickerColumns = this.picker.getColumns(); // 獲取列數(shù)據(jù)
        let columns = [];
        pickerColumns.forEach(function (col, i) {
            columns.push(0);
            col.options.forEach(function (opt) {
                if (opt && opt.text && opt.text.length > columns[i]) {
                    columns[i] = opt.text.length;
                }
            });
        });
        if (columns.length === 2) {
            let width = Math.max(columns[0], columns[1]);
            pickerColumns[0].align = "right";
            pickerColumns[1].align = "left";
            pickerColumns[0].optionsWidth = pickerColumns[1].optionsWidth = width * 17 + "px";
        }
        else if (columns.length === 3) {
            let width = Math.max(columns[0], columns[2]);
            pickerColumns[0].align = "right";
            pickerColumns[1].columnWidth = columns[1] * 33 + "px";
            pickerColumns[0].optionsWidth = pickerColumns[2].optionsWidth = width * 17 + "px";
            pickerColumns[2].align = "left";
        }
    }

    /**
     * 驗(yàn)證數(shù)據(jù)
     * @param picker
     */
    private validate(picker) {
        let _this = this;
        let columns = picker.getColumns();
        let provinceCol = columns[0];
        let cityCol = columns[1];
        let regionCol = columns[2];
        if (cityCol && this.provinceCol != provinceCol.selectedIndex) {
            cityCol.selectedIndex = 0;
            let cityColData = this.citiesData[provinceCol.selectedIndex].children;
            cityCol.options = cityColData.map(function (city) {
                return {text: city.name, value: city.code, disabled: false};
            });
            if (this.pickerColumnCmps && cityCol.options.length > 0) {
                setTimeout(function () {
                    return _this.pickerColumnCmps[1].setSelected(0, 100);
                }, 0);
            }
        }
        if (regionCol && (this.cityCol != cityCol.selectedIndex || this.provinceCol != provinceCol.selectedIndex)) {
            let regionData = this.citiesData[provinceCol.selectedIndex].children[cityCol.selectedIndex].children;
            regionCol.selectedIndex = 0;
            regionCol.options = regionData.map(function (city) {
                return {text: city.name, value: city.code, disabled: false};
            });
            if (this.pickerColumnCmps && regionCol.options.length > 0) {
                setTimeout(function () {
                    return _this.pickerColumnCmps[2].setSelected(0, 100);
                }, 0);
            }
        }
        this.provinceCol = provinceCol.selectedIndex;
        this.cityCol = cityCol ? cityCol.selectedIndex : 0;
        this.regionCol = regionCol ? regionCol.selectedIndex : 0;
    }

    /**
     *  設(shè)置value
     * @param newData
     */
    private setValue(newData) {
        if (newData === null || newData === undefined) {
            this.value = "";
        }
        else {
            this.value = newData;
        }
    }

    /**
     *  獲取value值
     * @returns {string}
     */
    private getValue() {
        return this.value;
    }

    /**
     *  改變value值的顯示
     * @param val
     */
    private onChange(val) {
        this.setValue(this.getString(val));
    }

    /**
     *  獲取當(dāng)前選擇的地區(qū)數(shù)據(jù)
     * @param newData
     * @returns {string}
     */
    private getString(newData) {
        if (newData["city"]) {
            if (newData["region"]) {
                return "" + newData["province"].text + this.separator + (newData["city"].text || "") + this.separator + (newData["region"].text || "");
            }
            return "" + newData["province"].text + this.separator + (newData["city"].text || "");
        }
        return "" + newData["province"].text;
    }
}

areasSelect.com.html
其實(shí)是不需要對(duì)應(yīng)的template的，但是為了能和父級(jí)傳參，這里創(chuàng)建了一個(gè)空的template

具體用法：
在需要用到的頁面調(diào)用
test.page.html

  地區(qū)選擇

test.page.ts

import {Component, ElementRef, Injector, ViewChild} from "@angular/core";
import {BasePage} from "../base.page";

@Component({
    templateUrl: "test.page.html",
    styles: []
})
export class TestPage extends BasePage {
    constructor(protected rt: ElementRef, protected ij: Injector) {
        super(rt, ij);
    }
    @ViewChild("areasSelect") areasSelect;
    showAreasSelect() {
        this.areasSelect.open();
    }
    done(data) {
        this.showAlert(JSON.stringify(data));
    }
    closeSelect() {
        this.showAlert("you click close");
    } 
}

沒有地區(qū)數(shù)據(jù)json或ts的文件可以去這里獲取
http://pan.baidu.com/s/1eRUJiXO