UI Foundation--uipikcerview implementation of provincial and municipal linkage example

Requirements:1. Display 2 columns of data, one column of data for the provincial city, and the other as the provincial counterparts in the city-level cities, and to choose from; 2. When selecting provincial cities, the corresponding column shows the city-level cities to which they are saved, and optionally; 3. When the provincial cities are re-selected, the corresponding city-level cities show City-level cities are not indexed at 0); implementation steps:1, build the interface, 2, the implementation of Uipikcerview agent method, 3, response to select events, 4, complete display selection data; Specific code:Model:

1 //2 //JWProvince.h3 //12-27-province4 //5 //Created by Xiaomoge on 14/12/27.6 //Copyright (c) 2014 Xiaomoge. All rights reserved.7 //8 9 #import<Foundation/Foundation.h>Ten  One @interfaceJwprovince:nsobject A@property (nonatomic,copy) NSString *name; -@property (nonatomic,strong) Nsarray *cities; --(Instancetype) Initwithdic: (Nsdictionary *) dic; the+ (Instancetype) Provincewithdic: (Nsdictionary *) dic; -+ (Nsmutablearray *) provincelist; - @end

1 //2 //JWPROVINCE.M3 //12-27-province4 //5 //Created by Xiaomoge on 14/12/27.6 //Copyright (c) 2014 Xiaomoge. All rights reserved.7 //8 9 #import "JWProvince.h"Ten  One @implementationjwprovince A-(Instancetype) Initwithdic: (Nsdictionary *) dic { -     if(self =[Super Init]) { - [self setvaluesforkeyswithdictionary:dic]; the     } -     returnSelf ; - } -+ (Instancetype) Provincewithdic: (Nsdictionary *) dic { +     return[[Self alloc] initwithdic:dic]; - } +  A+ (Nsmutablearray *) provincelist { atNsarray *array = [Nsarray arraywithcontentsoffile:[[nsbundle mainbundle] Pathforresource:@"Provinces"OfType:@"plist"]]; -      -Nsmutablearray *temparray =[Nsmutablearray array]; -      -      for(Nsdictionary *dicinchArray) { -Jwprovince *province =[Jwprovince provincewithdic:dic]; in [Temparray addobject:province]; -     } to     returnTemparray; + } - @end

Controller:

1 //2 //VIEWCONTROLLER.M3 //12-27-province4 //5 //Created by Xiaomoge on 14/12/27.6 //Copyright (c) 2014 Xiaomoge. All rights reserved.7 //8 9 #import "ViewController.h"Ten #import "JWProvince.h" One @interfaceViewcontroller () <UIPickerViewDelegate,UIPickerViewDataSource> A@property (nonatomic,strong) Nsarray *Provincedatas; - @property (nonatomic,assign) Nsinteger index; - @end the  - @implementationViewcontroller - #pragmaMark-Lazy Loading --(Nsarray *) Provincedatas { +     if(!_provincedatas) { -_provincedatas =[Jwprovince provincelist]; +     } A     return_provincedatas; at } - #pragmaMark-uipickerview Data source - //returns the number of columns that display data --(Nsinteger) Numberofcomponentsinpickerview: (Uipickerview *) Pickerview { -     return 2; - } in //returns the number of corresponding rows in each column --(Nsinteger) Pickerview: (Uipickerview *) Pickerview numberofrowsincomponent: (Nsinteger) component { to     if(Component = =0) { +         returnSelf.provinceDatas.count;//number of columns displayed in the first column -     } theJwprovince *pro =Self.provincedatas[self.index]; *     returnPro.cities.count;//number of columns shown in the second column $ }Panax Notoginseng #pragmaMark-uipickerview Agent - //returns the contents of each column and each row displayed the-(NSString *) Pickerview: (Uipickerview *) Pickerview Titleforrow: (nsinteger) Row forcomponent: (Nsinteger) component { +     if(Component = =0) { AJwprovince *pp =Self.provincedatas[row]; the         returnPp.name;//what is displayed in the first column +     } -Jwprovince *pro =Self.provincedatas[self.index]; $     returnPro.cities[row];//The second column shows the content $ } - #pragmaHow to select Mark-pickerview - //actions when a row is selected the- (void) Pickerview: (Uipickerview *) Pickerview Didselectrow: (nsinteger) Row incomponent: (Nsinteger) component { -     if(Component = =0) {WuyiSelf.index =Row; the[Pickerview reloadcomponent:1];//Reload the corresponding data -[Pickerview reloadallcomponents];//Reload all the data Wu[Pickerview SelectRow:0Incomponent:1Animated:yes];//The first row of every two columns is displayed after re-refreshing the data, regardless of whether the second column is selected in the previous row -     } About } $ @end

UI Foundation--uipikcerview implementation of provincial and municipal linkage example