UI控件之UIPickerView的协议方法

UIPickerView：选择视图，父类是UIView

UIPickerView *pickerView=[[UIPickerView alloc]initWithFrame:CGRectMake(10, 100, 300, 50)];

设置代理，通过代理设置显示样式和内容

pickerView.dataSource=self;

pickerView.delegate=self;

当列之间有关联时,要重新设置某列的值的同时进行刷新列,可以全部刷新,也可以刷新某一列

[pickerView reloadAllComponents];

[pickerView reloadComponent:2];

当pickerView重新成为第一响应者的时候刷新数据

[pickerView reloadInputViews];

pickerView的协议方法

<UIPickerViewDataSource,UIPickerViewDelegate>

设置列数

-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView

{

return 2;

}

设置每列的行数

-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component

{

if(component==0){

return 1;

}else{

return 2;

}

return _dataArray.count;

}

设置每列每行显示的view

-(UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view

{

//第1列显示内容

if(component==0){

}else{ //第2列显示内容

}

}

设置每列中项的高度

-(CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component

{

if(component==0){

return 60;

}else{

return 40;

}

}

设置每列的宽度

-(CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component

{

if(component==0)

return 200;

else

return 100;

}

当用户选择某行内容时执行，row是用户选择的行，component是用户选择的行所在的列

-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component

{

//如果用户操作的是第1列

if(component==0){

NSString *img=_dataArray[row];

//获取界面上当前显示的行数（在第几列）

NSInteger index=[pickerView selectedRowInComponent:1];

NSString *name=_dataArray[index];

NSLog(@"you choose image,%@,%@",img,name);

}else{

NSString *name=_dataArray[row];

NSInteger index=[pickerView selectedRowInComponent:0];

NSString *img=_dataArray[index];

NSLog(@"you choose name,%@,%@",img,name);

}

}

设置每列每行上显示的文本内容,component是列，row是行

-(NSString*)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component

{

if(component==0){

return @"Good";

}else{

if(row==0){

return @"Morning";

}else{

return @"Night";

}

}

}