前言
NS_CLASS_AVAILABLE_IOS(2_0) __TVOS_PROHIBITED @interface UIPickerView : UIView <NSCoding, UITableViewDataSource>
@available(iOS 2.0, *) public class UIPickerView : UIView, NSCoding, UITableViewDataSource
1、UIPickerView 的创建
遵守协议 UIPickerViewDataSource, UIPickerViewDelegate
-
Objective-C
// 实例化 UIPickerView 对象
UIPickerView *pickerView = [[UIPickerView alloc] init];
// 设置代理
pickerView.dataSource = self;
pickerView.delegate = self;
// 将 pickerView 添加到屏幕
[self.view addSubview:pickerView];
// 设置列数，必须设置，UIPickerViewDataSource 协议方法
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
return 3;
}
// 设置行数 ，必须设置，UIPickerViewDataSource 协议方法
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
return 10;
}
// 设置各行内容，必须设置，UIPickerViewDelegate 方法
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
return [NSString stringWithFormat:@"%li行 - %li列", row, component];
}
-
Swift
// 实例化 UIPickerView 对象
let pickerView:UIPickerView = UIPickerView()
// 设置代理
pickerView.dataSource = self
pickerView.delegate = self
// 将 pickerView 添加到屏幕
self.view.addSubview(pickerView)
// 设置列数，必须设置，UIPickerViewDataSource 协议方法
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
return 3
}
// 设置行数，必须设置，UIPickerViewDataSource 协议方法
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
return 10
}
// 设置各行内容，必须设置，UIPickerViewDelegate 方法
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
return String(format: "%li行 - %li列", row, component)
}
2、UIPickerView 的设置
-
Objective-C
// 设置默认值
[pickerView selectRow:1 inComponent:0 animated:YES]; // 第 0 列的默认值为 1
[pickerView selectRow:2 inComponent:1 animated:YES]; // 第 1 列的默认值为 2
[pickerView selectRow:3 inComponent:2 animated:YES]; // 第 2 列的默认值为 3
// 设置 frame
/*
高度只有三个值：162, 180 和 216，默认为 216，设置为其它的值无效
*/
pickerView.frame = CGRectMake(10, 30, self.view.bounds.size.width - 20, 162);
// 设置位置
pickerView.center = self.view.center;
// 设置背景颜色
pickerView.backgroundColor = [UIColor orangeColor];
// 是否显示指示器
/*
default is NO
*/
pickerView.showsSelectionIndicator = YES;
// 刷新指定的列
[pickerView reloadComponent:0];
// 刷新所有的列
[pickerView reloadAllComponents];
// 获取列数，只读
NSInteger numberOfComponents = pickerView.numberOfComponents;
// 获取指定列的行数
NSInteger numberOfRows = [pickerView numberOfRowsInComponent:0];
// 获取指定行的尺寸
CGSize rowSize = [pickerView rowSizeForComponent:0];
// 获取指定列被选中的行数索引
NSInteger selectedIndex = [pickerView selectedRowInComponent:0];
// 获取指定行列的视图
UIView *view = [pickerView viewForRow:3 forComponent:0];
// 设置列宽
/*
不设置时为默认宽度，UIPickerViewDelegate 方法
*/
- (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component {
return 50;
}
// 设置行高
/*
不设置时为默认高度 32，UIPickerViewDelegate 方法
*/
- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component {
return 50;
}
-
Swift
// 设置默认值
pickerView.selectRow(1, inComponent: 0, animated: true) // 第 0 列的默认值为 1
pickerView.selectRow(2, inComponent: 1, animated: true) // 第 1 列的默认值为 2
pickerView.selectRow(3, inComponent: 2, animated: true) // 第 2 列的默认值为 3
// 设置 frame
/*
高度只有三个值：162, 180 和 216，默认为 216，设置为其它的值无效
*/
pickerView.frame = CGRectMake(10, 30, self.view.bounds.size.width - 20, 162)
// 设置位置
pickerView.center = self.view.center
// 设置背景颜色
pickerView.backgroundColor = UIColor.orangeColor()
// 是否显示指示器
/*
default is NO
*/
pickerView.showsSelectionIndicator = true
// 刷新指定的列
pickerView.reloadComponent(0)
// 刷新所有的列
pickerView.reloadAllComponents()
// 获取列数，只读
let numberOfComponents:Int = pickerView.numberOfComponents
// 获取指定列的行数
let numberOfRows:Int = pickerView.numberOfRowsInComponent(0)
// 获取指定行的尺寸
let rowSize:CGSize = pickerView.rowSizeForComponent(0)
// 获取指定列被选中的行数索引
let selectedIndex:Int = pickerView.selectedRowInComponent(0)
// 获取指定行列的视图
let view:UIView? = pickerView.viewForRow(3, forComponent: 0)
// 设置列宽
/*
不设置时为默认宽度，UIPickerViewDelegate 方法
*/
func pickerView(pickerView: UIPickerView, widthForComponent component: Int) -> CGFloat {
return 50
}
// 设置行高
/*
不设置时为默认高度 32，UIPickerViewDelegate 方法
*/
func pickerView(pickerView: UIPickerView, rowHeightForComponent component: Int) -> CGFloat {
return 50
}
3、UIPickerViewDataSource 协议方法
-
Objective-C
// 设置列数
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
}
// 设置行数
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
}
-
Swift
// 设置列数
func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
}
// 设置行数
func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
}
4、UIPickerViewDelegate 协议方法
-
Objective-C
// 设置各行内容为 字符串
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
}
// 设置各行内容为 NSAttributedString 型字符串
- (NSAttributedString *)pickerView:(UIPickerView *)pickerView attributedTitleForRow:(NSInteger)row forComponent:(NSInteger)component {
}
// 设置各行内容为 view
- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view {
}
// 设置列宽
- (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component {
}
// 设置行高
- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component {
}
// 检测行的选择状态，在滑动停止后触发
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
}
-
Swift
// 设置各行内容为 字符串
func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
}
// 设置各行内容为 NSAttributedString 型字符串
func pickerView(pickerView: UIPickerView, attributedTitleForRow row: Int, forComponent component: Int) -> NSAttributedString? {
}
// 设置各行内容为 view
func pickerView(pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusingView view: UIView?) -> UIView {
}
// 设置列宽
func pickerView(pickerView: UIPickerView, widthForComponent component: Int) -> CGFloat {
}
// 设置行高
func pickerView(pickerView: UIPickerView, rowHeightForComponent component: Int) -> CGFloat {
}
// 检测行的选择状态，在滑动停止后触发
func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
}
