UIPickerView的使用

UIPickerView功能與UIDatePicker類似

初始化實例時，通常只需要設置原點坐標，不需要設置寬高（默認寬高為：frame = (0 0; 320 216)）

區別在於:

1、UIPickerView需要自定義實現數據類型（包括：數據源，列數等）

1. @interfaceViewController()
2.  
3. @property(nonatomic,strong)NSDictionary*sourceDict;
4. @property(nonatomic,strong)NSString*rowTitleFirst;
5. @property(nonatomic,strong)NSString*rowTitleSecond;
6. @property(nonatomic,strong)NSString*rowTitleThird;
7.  
8. @property(nonatomic,strong)UITextField*textfield;
9.  
10. @end
11. UIPickerView*pickerView=[[UIPickerViewalloc]init];
12. //[self.viewaddSubview:pickerView];
13. pickerView.backgroundColor=[UIColororangeColor];
14. NSLog(@"pickerView%@",pickerView);
15. /*
16. 設置代理
17. 1包括代理對象，及數據源代理對象
18. 2實現代理方法的對象
19. 3添加協議
20. 4實現代理方法
21.  
22. 注意事項
23. 1、兩種代理必須同時實現
24. 2、標題顯示設置三選一，只設置其中一個方法即可
25. 2-1、-(nullableNSString*)pickerView:(UIPickerView*)pickerViewtitleForRow:(NSInteger)rowforComponent:(NSInteger)component
26. 2-2、-(nullableNSAttributedString*)pickerView:(UIPickerView*)pickerViewattributedTitleForRow:(NSInteger)rowforComponent:(NSInteger)component
27. 2-3、-(UIView*)pickerView:(UIPickerView*)pickerViewviewForRow:(NSInteger)rowforComponent:(NSInteger)componentreusingView:(nullableUIView*)view
28. */
29. pickerView.delegate=self;
30. pickerView.dataSource=self;
31. //設置數據源
32. NSArray*meizhouArray=@[@"梅縣",@"五華縣",@"豐順縣",@"大埔縣",@"蕉嶺縣",@"興寧市",@"梅江區"];
33. NSArray*guangzhouArray=@[@"天河區",@"白雲區",@"荔灣區",@"番禺區",@"海珠區",@"花都區",@"從化區",@"增城區"];
34. NSArray*shenzhenArray=@[@"龍華新區",@"大鵬新區",@"福田區",@"羅湖區",@"寶安區",@"龍崗區",@"南山區"];
35. NSDictionary*guangdongCityDict=[NSDictionarydictionaryWithObjectsAndKeys:shenzhenArray,@"深圳市",guangzhouArray,@"廣州市",meizhouArray,@"梅州市",nilnil];
36. NSDictionary*guangxiCityDict=[NSDictionarydictionaryWithObjectsAndKeys:@[],@"柳州市",@[],@"桂林市",nilnil];
37. self.sourceDict=[NSDictionarydictionaryWithObjectsAndKeys:guangdongCityDict,@"廣東省",guangxiCityDict,@"廣西省",nilnil];
38. //設置默認值
39. self.rowTitleFirst=@"廣東省";
40. self.rowTitleSecond=@"深圳市";
41. [pickerViewselectRow:0inComponent:0animated:NO];
42. [pickerViewselectRow:0inComponent:1animated:NO];
43. [pickerViewselectRow:3inComponent:2animated:NO];
44. //刷新數據
45. [pickerViewreloadAllComponents];
46. //通過textfield來使用
47. self.textfield=[[UITextFieldalloc]initWithFrame:CGRectMake(10.0,50.0,(CGRectGetWidth(self.view.bounds)-10.0*2),40.0)];
48. [self.viewaddSubview:self.textfield];
49. self.textfield.backgroundColor=[UIColoryellowColor];
50. self.textfield.textColor=[UIColorredColor];
51. self.textfield.placeholder=@"請選擇地址（省市區）";
52. //添加鍵盤上方的子視圖
53. UIButton*button=[UIButtonbuttonWithType:UIButtonTypeCustom];
54. button.frame=CGRectMake(0.0,0.0,CGRectGetWidth(self.view.bounds),40.0);
55. button.backgroundColor=[UIColorgreenColor];
56. [buttonsetTitleColor:[UIColorblackColor]forState:UIControlStateNormal];
57. [buttonsetTitleColor:[UIColorredColor]forState:UIControlStateHighlighted];
58. [buttonsetTitle:@"隱藏鍵盤"forState:UIControlStateNormal];
59. [buttonaddTarget:selfaction:@selector(hiddenKeyboard:)forControlEvents:UIControlEventTouchUpInside];
60. self.textfield.inputAccessoryView=button;
61. //輸入源改成地址選擇視圖
62. self.textfield.inputView=pickerView;
63. //UIPickerViewDelegate
64.  
65. -(CGFloat)pickerView:(UIPickerView*)pickerViewwidthForComponent:(NSInteger)component
66. {
67. //設置列的寬度
68. return100.0;
69. }
70.  
71. -(CGFloat)pickerView:(UIPickerView*)pickerViewrowHeightForComponent:(NSInteger)component
72. {
73. //設置列中的每行的高度
74. return40.0;
75. }
76.  
77. -(nullableNSString*)pickerView:(UIPickerView*)pickerViewtitleForRow:(NSInteger)rowforComponent:(NSInteger)component
78. {
79. //設置列中的每行的顯示標題NSString
80.  
81. //設置每列每行的標題
82. NSArray*keyArray=self.sourceDict.allKeys;
83. if(0==component)
84. {
85. NSString*title=keyArray[row];
86. returntitle;
87. }
88. elseif(1==component)
89. {
90. NSDictionary*cityDict=self.sourceDict[self.rowTitleFirst];
91. NSArray*cityArray=cityDict.allKeys;
92. NSString*title=cityArray[row];
93. returntitle;
94. }
95. elseif(2==component)
96. {
97. NSDictionary*areaDict=self.sourceDict[self.rowTitleFirst];
98. NSArray*areaArray=areaDict[self.rowTitleSecond];
99. NSString*title=areaArray[row];
100. returntitle;
101. }
102.  
103. returnnil;
104. }
105.  
106. //-(nullableNSAttributedString*)pickerView:(UIPickerView*)pickerViewattributedTitleForRow:(NSInteger)rowforComponent:(NSInteger)component
107. //{
108. ////設置列中的每行的顯示標題NSAttributedString
109. //returnnil;
110. //}
111.  
112. //-(UIView*)pickerView:(UIPickerView*)pickerViewviewForRow:(NSInteger)rowforComponent:(NSInteger)componentreusingView:(nullableUIView*)view
113. //{
114. ////設置列中的每行的自定義視圖
115. //returnnil;
116. //}
117.  
118. -(void)pickerView:(UIPickerView*)pickerViewdidSelectRow:(NSInteger)rowinComponent:(NSInteger)component
119. {
120. //獲取列中選中的某一行
121.  
122. NSLog(@"component=%ld,row=%ld",component,row);
123.  
124. NSArray*keyArray=self.sourceDict.allKeys;
125. if(0==component)
126. {
127. NSString*keyFirst=keyArray[row];
128. //設置第一列的值，即key1
129. self.rowTitleFirst=keyFirst;
130. //當第一列改變時，第二列的值應該跟著改變，即key2，設置為默認第二列的第一個值
131. NSDictionary*cityDict=self.sourceDict[self.rowTitleFirst];
132. NSArray*cityArray=cityDict.allKeys;
133. if(cityArray&&0 {
134. NSString*keySecond=cityArray[0];
135. self.rowTitleSecond=keySecond;
136. }
137. //設置第三個標題，當第二列改變時，第三wfhr值路著改變
138. NSArray*areaArray=cityDict[self.rowTitleSecond];
139. if(areaArray&&0 {
140. NSString*keyThird=areaArray[0];
141. self.rowTitleThird=keyThird;
142. }
143. else
144. {
145. //沒有第三列時，將第三列的默認標題設置為空
146. self.rowTitleThird=nil;
147. }
148.  
149. //重新刷新第2列的數據，且設置顯示為第一行
150. [pickerViewreloadComponent:1];
151. [pickerViewselectRow:0inComponent:1animated:YES];
152.  
153. //重新刷新第3列的數據，且設置顯示為第一行
154. [pickerViewreloadComponent:2];
155. [pickerViewselectRow:0inComponent:2animated:YES];
156. }
157. elseif(1==component)
158. {
159. //設置第二個標題
160. NSDictionary*cityDict=self.sourceDict[self.rowTitleFirst];
161. NSArray*cityArray=cityDict.allKeys;
162. NSString*keySecond=cityArray[row];
163. self.rowTitleSecond=keySecond;
164.  
165. //設置第三個標題，默認第一行
166. NSArray*areaArray=cityDict[self.rowTitleSecond];
167. if(areaArray&&0 {
168. NSString*keyThird=areaArray[0];
169. self.rowTitleThird=keyThird;
170. }
171.  
172.  
173. //重新刷新第3列的數據，且設置顯示為第一行
174. [pickerViewreloadComponent:2];
175. [pickerViewselectRow:0inComponent:2animated:YES];
176. }
177. elseif(2==component)
178. {
179. //設置第三個標題
180. NSDictionary*cityDict=self.sourceDict[self.rowTitleFirst];
181. NSArray*areaArray=cityDict[self.rowTitleSecond];
182. if(areaArray&&0 {
183. NSString*keyThird=areaArray[row];
184. self.rowTitleThird=keyThird;
185. }
186. }
187.  
188. NSString*text=[NSStringstringWithFormat:@"%@%@%@",self.rowTitleFirst,self.rowTitleSecond,self.rowTitleThird];
189. NSLog(@"選擇結果：%@",text);
190.  
191. self.textfield.text=text;
192. }
193. //UIPickerViewDataSource
194.  
195. //returnsthenumberof'columns'todisplay.
196. -(NSInteger)numberOfComponentsInPickerView:(UIPickerView*)pickerView
197. {
198. //設置列數
199.  
200. //設置三列：省、市、區
201. return3;
202. }
203.  
204. //returnsthe#ofrowsineachcomponent..
205. -(NSInteger)pickerView:(UIPickerView*)pickerViewnumberOfRowsInComponent:(NSInteger)component
206. {
207. //設置每列的行數
208.  
209. //設置每列的實際行數
210. NSArray*keyArray=self.sourceDict.allKeys;
211. if(0==component)
212. {
213. returnkeyArray.count;
214. }
215. elseif(1==component)
216. {
217. NSDictionary*cityDict=self.sourceDict[self.rowTitleFirst];
218. NSArray*cityArray=cityDict.allKeys;
219. returncityArray.count;
220. }
221. elseif(2==component)
222. {
223. NSDictionary*areaDict=self.sourceDict[self.rowTitleFirst];
224. NSArray*areaArray=areaDict[self.rowTitleSecond];
225. returnareaArray.count;
226. }
227.  
228. return0;
229. }
230. //隱藏鍵盤
231. -(void)hiddenKeyboard:(UIButton*)button
232. {
233. [self.viewendEditing:YES];
234. }