利用Ionic2 + angular4实现一个地区选择组件

前言

本文主要给大家介绍的是关于利用ionic2 + angular4实现一个地区选择组件的相关内容，为什么会有这篇文章？主要是因为最近在项目重构的过程中，发现之前用mobiscroll写的地区选择指令在angular2中很难重用（毕竟是用typescript）。于是就萌生了自己写一个组件的想法。

想和之前一样基于mobiscroll去写，但是发现非常耗费精力，于是某日万般无奈这下搜了一下相关的组件，不出所料已经有人写了。...但是此组件并不符合我的要求。我不是单纯的选择省市区，还可能是选择省市或者省。于是参照此项目基于ionic2的picker写了一个公用组件。下面话不多说了，感兴趣的朋友们下面来一起看看详细的介绍：

具体代码如下：

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; // 区列
 private pickercolumncmps; // picker纵列数据实例
 private isopen = false; // 是否被创建
 private pickercmp; // picker 实例
 private value = ''; // 选中后的数据
 @input() citiesdata = areaslist;　// 地区数据(默认为areas.ts的数据)
 @input() canceltext = '关闭'; // 关闭按钮文本
 @input() donetext = '完成'; // 完成按钮文本
 @input() separator = ''; // 数据衔接模式
 @input() level = 3; // 等级设置 最高为三级
 /**
 * 关闭时触发的事件
 * 没有值返回
 * @type {eventemitter}
 */
 @output() cancel: eventemitter<any> = new eventemitter(); // 关闭事件
 /**
 * 完成时触发的事件
 * 返回值为obj
 * obj = {data: object,value: string} data为对应的省市区和编码
 * @type {eventemitter}
 */
 @output() done: eventemitter<any> = new eventemitter(); // 完成事件
 /**
 * 打开地区选择器
 * 基本思路
 * 1.创建picker
 * 2. 先把数据处理成省市区分开的数组
 * 3. 将数据以列的形式给到picker
 * 4. 设置数据显示样式（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();// 加载
 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;
 });
 }

 /** 对数据进行处理，并移交给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);
 }

 /**设置数据显示样式
 * @param picker
 */
 private divycolumns(picker) {
 let pickercolumns = this.picker.getcolumns(); // 获取列数据
 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';
 }
 }

 /**
 * 验证数据
 * @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;
 }

 /**
 * 设置value
 * @param newdata
 */
 private setvalue(newdata) {
 if (newdata === null || newdata === undefined) {
 this.value = '';
 }
 else {
 this.value = newdata;
 }
 }

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

 /**
 * 改变value值的显示
 * @param val
 */
 private onchange(val) {
 this.setvalue(this.getstring(val));
 }

 /**
 * 获取当前选择的地区数据
 * @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

其实是不需要对应的template的，但是为了能和父级传参，这里创建了一个空的template

<div></div>

具体用法：

在需要用到的页面调用

test.page.html

<ion-content>
 <button ion-button block icon-left color="light" (tap)="showareasselect()">地区选择</button>
</ion-content>
<areas-select #areasselect [level]="3" (cancel)="closeselect()" (done)="done($event)"></areas-select>

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');
 } 
}

没有地区数据json或ts的文件可以去这里获取：

总结

以上就是这篇文章的全部内容了，希望本文的内容对大家的学习或者工作能带来一定的帮助，如果有疑问大家可以留言交流，谢谢大家对的支持。