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在IOS中,實現表格展示數據,最常用的做法就是使用UITableView.
@interface UITableView : UIScrollView <NSCoding>UITableView繼承自UIScrollView,所以支持垂直滾動,而且性能極佳(這個會在以后提到,支持重用cell)
UITableView有兩種樣式:分組和不分組
分組:UITableViewStyleGrouped
不分組:UITableViewStylePlain
@PRoperty (nonatomic, readonly) UITableViewStyle style;@property (nonatomic, assign) id <UITableViewDataSource> dataSource;@property (nonatomic, assign) id <UITableViewDelegate> delegate;@property (nonatomic) CGFloat rowHeight; // will return the default value if unset
1.UITableView需要一個數據源(dataSource)來顯示數據(如上面代碼)
2.UITableView會向數據源查詢一共有多少行數據以及每一行顯示什么數據等
@protocol UITableViewDataSource<NSObject>@required- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section;// Row display. Implementers should *always* try to reuse cells by setting each cell's reuseIdentifier and querying for available reusable cells with dequeueReusableCellWithIdentifier:// Cell gets various attributes set automatically based on table (separators) and data source (accessory views, editing controls)- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath;@optional- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView; // Default is 1 if not implemented- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section; // fixed font style. use custom view (UILabel) if you want something different- (NSString *)tableView:(UITableView *)tableView titleForFooterInSection:(NSInteger)section;// Editing// Individual rows can opt out of having the -editing property set for them. If not implemented, all rows are assumed to be editable.- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath;// Moving/reordering// Allows the reorder accessory view to optionally be shown for a particular row. By default, the reorder control will be shown only if the datasource implements -tableView:moveRowAtIndexPath:toIndexPath:- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath;// Index- (NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView; // return list of section titles to display in section index view (e.g. "ABCD...Z#")- (NSInteger)tableView:(UITableView *)tableView sectionForSectionIndexTitle:(NSString *)title atIndex:(NSInteger)index; // tell table which section corresponds to section title/index (e.g. "B",1))// Data manipulation - insert and delete support// After a row has the minus or plus button invoked (based on the UITableViewCellEditingStyle for the cell), the dataSource must commit the change// Not called for edit actions using UITableViewRowAction - the action's handler will be invoked instead- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath;// Data manipulation - reorder / moving support- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)sourceIndexPath toIndexPath:(NSIndexPath *)destinationIndexPath;@end
3.沒有設置數據元的UITableView只是一個空的殼子,不會展示任何數據
4.上面代碼是UITableViewDataSource協議的,凡是遵守UITableViewDataSource協議的OC對象,都可以是UITableView的數據源,此處我們一般選擇控制器為數據源.
所以總結一下使用UITableView展示數據的步驟:
UITableViewDataSource協議中必須要實現的方法:
@required//每一組有多少行- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section;// Row display. Implementers should *always* try to reuse cells by setting each cell's reuseIdentifier and querying for available reusable cells with dequeueReusableCellWithIdentifier:// Cell gets various attributes set automatically based on table (separators) and data source (accessory views, editing controls)//每一行顯示什么樣的內容- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath;
下面這個方法不是必須要實現的,不實現默認就是1組
//一共有多少組- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView;//這個方法不是必須要實現的,如果不實現,就默認是一組
下面通過一個小例子來演示UITableView的使用
下圖是應用代碼結構及plist文件截圖:
此處的plist文件相對于前面文章介紹的比較復雜,此處是字典中又包含字典,所以使用的字典轉模型的方法與之前也有所不同.首先要將里面的字典先轉化為模型,再轉化外面的.
上圖中標注的KZCar是汽車數據模型
上圖中標注的KZCarGroup是汽車組的數據模型,下面附上代碼,其中尤其要注意,這個復雜的數據模型的轉化過程.
KZCar.h
1 // 2 // KZCar.h 3 // UI基礎-06-05-19 4 // 5 // Created by hukezhu on 15/5/20. 6 // 7 // 8 9 #import <Foundation/Foundation.h>10 11 @interface KZCar : NSObject12 13 /**14 * 聲明圖片屬性15 */16 @property (nonatomic,copy) NSString *icon;17 18 /**19 * 聲明名稱屬性20 */21 @property (nonatomic,copy) NSString *name;22 23 24 -(instancetype)initWithDict:(NSDictionary *)dict;25 26 +(instancetype)carWithDict:(NSDictionary *)dict;27 28 +(NSArray *)carsWithDict:(NSArray *)dictarray;29 @end
KZCar.m
1 // 2 // KZCar.m 3 // UI基礎-06-05-19 4 // 5 // Created by hukezhu on 15/5/20. 6 // 7 // 8 9 #import "KZCar.h"10 11 @implementation KZCar12 13 -(instancetype)initWithDict:(NSDictionary *)dict{14 15 if (self = [super init]) {16 //使用KVC17 [self setValuesForKeysWithDictionary:dict];18 }19 return self;20 }21 22 23 +(instancetype)carWithDict:(NSDictionary *)dict{24 25 return [[self alloc]initWithDict:dict];26 }27 28 //此處是里面的汽車數據模型,分析汽車數組轉化的時候,發現此處只需要傳入一個數組即可29 +(NSArray *)carsWithDict:(NSArray *)dictarray{30 31 32 NSMutableArray *tempArray = [NSMutableArray array];33 for (NSDictionary *dict in dictarray) {34 KZCar *car = [KZCar carWithDict:dict];35 [tempArray addObject:car];36 }37 return tempArray;38 }39 @end
KZCarGroup.h//// KZCarGroup.h// UI基礎-06-05-19//// Created by hukezhu on 15/5/20.////#import <Foundation/Foundation.h>@interface KZCarGroup : NSObject/** * 聲明一個汽車的屬性 */@property (nonatomic,strong)NSArray *cars;/** * 聲明一個標題的屬性 */@property (nonatomic,copy)NSString *title;-(instancetype)initWithDict:(NSDictionary *)dict;+(instancetype)carGroupWithDict:(NSDictionary *)dict;+(NSArray *)carGroups;@end
KZCarGroup.m
1 // 2 // KZCarGroup.m 3 // UI基礎-06-05-19 4 // 5 // Created by hukezhu on 15/5/20. 6 // 7 // 8 9 #import "KZCarGroup.h"10 #import "KZCar.h"11 12 @implementation KZCarGroup13 -(instancetype)initWithDict:(NSDictionary *)dict{14 15 if (self = [super init]) {16 _title = dict[@"title"];17 18 //將字典中的數組cars取出來19 NSArray *array = dict[@"cars"];20 _cars = [KZCar carsWithDict:array];21 }22 return self;23 }24 25 +(instancetype)carGroupWithDict:(NSDictionary *)dict{26 27 return [[self alloc]initWithDict:dict];28 }29 30 +(NSArray *)carGroups{31 32 33 NSString *path = [[NSBundle mainBundle]pathForResource:@"cars_total" ofType:@"plist"];34 NSArray *dictArray = [NSArray arrayWithContentsOfFile:path];35 36 NSMutableArray *tempArray = [NSMutableArray array];37 for (NSDictionary *dict in dictArray) {38 KZCarGroup *carGroup = [KZCarGroup carGroupWithDict:dict];39 [tempArray addObject:carGroup];40 }41 return tempArray;42 }43 @end
ViewController.m
1 // 2 // ViewController.m 3 // 05-car多數據 4 // 5 // Created by hukezhu on 15/5/20. 6 // 7 8 9 10 11 #import "ViewController.h" 12 #import "KZCarGroup.h" 13 #import "KZCar.h" 14 15 @interface ViewController ()<UITableViewDataSource> 16 17 @property (weak, nonatomic) IBOutlet UITableView *tableView; 18 19 20 21 @property(nonatomic,strong)NSArray *cars; 22 @end 23 24 @implementation ViewController 25 26 - (void)viewDidLoad { 27 [super viewDidLoad]; 28 29 self.tableView.dataSource = self; 30 NSLog(@"%@",self.cars); 31 32 } 33 #pragma mark -數據源方法 34 /** 35 * 返回一共有多少組 36 37 */ 38 -(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{ 39 40 return self.cars.count; 41 } 42 43 /** 44 * 返回每一組有多少行 45 * 46 */ 47 -(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{ 48 49 KZCarGroup *carGroup = self.cars[section]; 50 return carGroup.cars.count; 51 } 52 53 /** 54 * 返回每行顯示什么樣的數據 55 * 56 */ 57 -(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{ 58 59 NSString *identity = @"yes"; 60 UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:identity ]; 61 62 if (cell == nil) { 63 cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identity]; 64 } 65 //取出組模型 66 KZCarGroup *carGroup = self.cars[indexPath.section]; 67 //取出行模型 68 KZCar *car = carGroup.cars[indexPath.row]; 69 70 cell.imageView.image = [UIImage imageNamed:car.icon]; 71 cell.textLabel.text = car.name; 72 return cell; 73 } 74 75 76 /** 77 * 設置頭部biaoti 78 * 79 */ 80 -(NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section{ 81 82 //取出組模型 83 KZCarGroup *carGroup = self.cars[section]; 84 return carGroup.title; 85 86 } 87 88 /** 89 * 設置尾部描述 90 * 91 */ 92 -(NSString *)tableView:(UITableView *)tableView titleForFooterInSection:(NSInteger)section{ 93 94 //取出組模型 95 KZCarGroup *carGroup = self.cars[section]; 96 return carGroup.title; 97 98 } 99 /**100 * 懶加載數據101 *102 */103 -(NSArray *)cars{104 105 if (_cars == nil) {106 _cars = [KZCarGroup carGroups];107 }108 return _cars;109 }110 @end
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