I want to know how can i make a generic/single UIPickerView
to display in multiple ViewControllers
.
I want to show a pickerView in multiple ViewController. Now how can i create it.
I know how to create it like implement and write its delegate for it..
But i don't want to create these delegate in each class and write those method again and agian..
What have i done..
I have created a new File and inherit it with UIPickerView
. and create an NSArray property
to show in it. and also implemented its delegate but now onward don't know how to do it .
Show me some sort of example to make a generic UIPickerView or help me creating it..
One way to do this would be to create a class with a completion handler that creates the picker and acts as its data source and delegate. For example, in the .h file, you could do something like this,
typedef void(^completionHandler) (NSString *selectedString);
@interface RDPickerController : NSObject <UIPickerViewDataSource, UIPickerViewDelegate>
@property (strong,nonatomic) UIPickerView *picker;
-(instancetype)initWithCompletionHandler:(completionHandler) completion;
In the .m file, implement any of the data source and delegate methods that you need, and call the completion block in the pickerView:didSelectRow:inComponent: method,
@interface RDPickerController ()
@property (strong,nonatomic) NSArray *data;
@property (copy,nonatomic) completionHandler compBlock;
@end
@implementation RDPickerController
-(instancetype)initWithCompletionHandler:(completionHandler)completion {
if (self = [super init]) {
_picker = [UIPickerView new];
_picker.delegate = self;
_picker.dataSource = self;
_data = @[@"One", @"Two", @"Three", @"Four", @"Five", @"Six", @"Seven", @"Eight", @"Nine", @"Ten"];
_compBlock = completion;
}
return self;
}
-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView {
return 1;
}
-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
return self.data.count;
}
-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
return self.data[row];
}
-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
self.compBlock(self.data[row]);
}
In your controller classes, you can create and use the picker like this,
@interface ViewController ()
@property (strong,nonatomic) RDPickerController *pc;
@end
@implementation ViewController
- (IBAction)showPicker:(UIButton *)sender {
self.pc = [[RDPickerController alloc] initWithCompletionHandler:^(NSString *selectedString) {
NSLog(@"%@",selectedString);
// do whatever with the returned data here
}];
[self.view addSubview:self.pc.picker];
}