Android PickerView实现三级联动效果

github有一个开源控件pickerview，可以实现三级联动的效果。虽然该控件使用非常简单，但是填充数据异常繁琐。github上的demo在填充数据的时候是一条一条地填充的，代码过于冗余。下面提供一种简便的方式来实现。

(1)在app目录下新建一个assets文件夹，将province_data.xml文件复制到该文件夹下，该xml文件里保存了全国的省市县的地址数据。

(2)使用sax解析xml文件中的数据，并将数据填充到pickerview这个控件中。

—provincemodel—

public class provincemodel implements ipickerviewdata
{
  private string name;
  private list<citymodel> citylist;

  public provincemodel()
  {
    super();
  }

  public string getname()
  {
    return name;
  }

  public void setname(string name)
  {
    this.name = name;
  }

  public list<citymodel> getcitylist()
  {
    return citylist;
  }

  public void setcitylist(list<citymodel> citylist)
  {
    this.citylist = citylist;
  }

  @override
  public string getpickerviewtext()
  {
    return name;
  }
}

—citymodel—

public class citymodel implements ipickerviewdata
{
  private string name;
  private list<districtmodel> districtlist;

  public citymodel()
  {
    super();
  }

  public string getname()
  {
    return name;
  }

  public void setname(string name)
  {
    this.name = name;
  }

  public list<districtmodel> getdistrictlist()
  {
    return districtlist;
  }

  public void setdistrictlist(list<districtmodel> districtlist)
  {
    this.districtlist = districtlist;
  }

  @override
  public string tostring()
  {
    return name;
  }

  @override
  public string getpickerviewtext()
  {
    return name;
  }
}

—districtmodel—

public class districtmodel implements ipickerviewdata
{
  private string name;
  private string zipcode;

  public districtmodel()
  {
    super();
  }

  public string getzipcode()
  {
    return zipcode;
  }

  public void setzipcode(string zipcode)
  {
    this.zipcode = zipcode;
  }

  public string getname()
  {
    return name;
  }

  public void setname(string name)
  {
    this.name = name;
  }

  @override
  public string tostring()
  {
    return name;
  }

  @override
  public string getpickerviewtext()
  {
    return name;
  }
}

—xmlparserhandler—

public class xmlparserhandler extends defaulthandler
{
  /**
   *  存储所有的解析对象
   */
  private list<provincemodel> provincelist = new arraylist<>();
  private provincemodel provincemodel = new provincemodel();
  private citymodel citymodel = new citymodel();
  private districtmodel districtmodel = new districtmodel();

  public xmlparserhandler(){}

  public list<provincemodel> getdatalist()
  {
    return provincelist;
  }

  @override
  public void startdocument() throws saxexception
  {
    super.startdocument();
  }

  @override
  public void enddocument() throws saxexception
  {
    super.enddocument();
  }

  @override
  public void startelement(string uri, string localname, string qname, attributes attributes) throws saxexception
  {
    if (qname.equals("province"))
    {
      provincemodel = new provincemodel();
      provincemodel.setname(attributes.getvalue(0));
      provincemodel.setcitylist(new arraylist<citymodel>());
    }
    else if (qname.equals("city"))
    {
      citymodel = new citymodel();
      citymodel.setname(attributes.getvalue(0));
      citymodel.setdistrictlist(new arraylist<districtmodel>());
    }
    else if (qname.equals("district"))
    {
      districtmodel = new districtmodel();
      districtmodel.setname(attributes.getvalue(0));
      districtmodel.setzipcode(attributes.getvalue(1));
    }
  }

  @override
  public void endelement(string uri, string localname, string qname) throws saxexception
  {
    if(qname.equals("district"))
    {
      citymodel.getdistrictlist().add(districtmodel);
    }
    else if(qname.equals("city"))
    {
      provincemodel.getcitylist().add(citymodel);
    }
    else if(qname.equals("province"))
    {
      provincelist.add(provincemodel);
    }
  }

  @override
  public void characters(char[] ch, int start, int length) throws saxexception
  {
    super.characters(ch, start, length);
  }
}

public class addressaddactivity extends baseactivity
{
  private optionspickerview mcitypickerview;
  private arraylist<provincemodel> mprovinces = new arraylist<>();
  private arraylist<arraylist<citymodel>> mcities = new arraylist<>();
  private arraylist<arraylist<arraylist<districtmodel>>> mdistricts = new arraylist<>();

  @override
  protected void oncreate(@nullable bundle savedinstancestate)
  {
    super.oncreate(savedinstancestate);
    supportrequestwindowfeature(window.feature_no_title);
    setcontentview(r.layout.activity_address_add);
    viewutils.inject(this);
    init();
  }

  private void init()
  {
    initprovincedatas();
    try
    {
      //选项选择器
      mcitypickerview = new optionspickerview(this);
      mcitypickerview.setpicker( mprovinces, mcities, mdistricts, true);
      mcitypickerview.settitle("选择城市");
      mcitypickerview.setcyclic(false, false , false);
      mcitypickerview.setonoptionsselectlistener(new optionspickerview.onoptionsselectlistener() {
        @override
        public void onoptionsselect(int options1, int option2, int options3)
        {
          string address = mprovinces.get(options1).getname() + " "
              + mcities.get(options1).get(option2) + " "
              + mdistricts.get(options1).get(option2).get(options3);
          mtxtaddress.settext(address);
        }
      });
    }
    catch (exception e)
    {
      e.printstacktrace();
    }
  }

  @onclick(r.id.ll_city_picker)
  public void showpickerview(view view)
  {
    mcitypickerview.show();
  }

  protected void initprovincedatas()
  {
    assetmanager asset = getassets();
    try
    {
      inputstream input = asset.open("province_data.xml");
      saxparserfactory spf = saxparserfactory.newinstance();
      saxparser parser = spf.newsaxparser();
      xmlparserhandler handler = new xmlparserhandler();
      parser.parse(input , handler);
      input.close();
      //获取解析出来的数据
      mprovinces = (arraylist<provincemodel>) handler.getdatalist();
    }
    catch (throwable e)
    {
      e.printstacktrace();
    }

    if (mprovinces != null)
    {
      for (provincemodel p : mprovinces)
      {
        list<citymodel> cities = p.getcitylist();
        //组装城市数据
        mcities.add((arraylist<citymodel>) cities);
        arraylist<arraylist<districtmodel>> dts = new arraylist<>();
        for (citymodel c : cities)
        {
          list<districtmodel> districts = c.getdistrictlist();
          dts.add((arraylist<districtmodel>) districts);
        }
        mdistricts.add(dts);
      }
    }
  }
}

到此完毕，很简单的例子。

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。