react-native/React/Views/RCTPicker.m
Nick Lockwood 48af214216 Simplified event registration
Summary:
Our events all follow a common pattern, so there's no good reason why the configuration should be so verbose. This diff eliminates that redundancy, and gives us the freedom to simplify the underlying mechanism in future without further churning the call sites.
2015-08-11 06:41:04 -08:00

107 lines
2.5 KiB
Objective-C

/**
* Copyright (c) 2015-present, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under the BSD-style license found in the
* LICENSE file in the root directory of this source tree. An additional grant
* of patent rights can be found in the PATENTS file in the same directory.
*/
#import "RCTPicker.h"
#import "RCTConvert.h"
#import "RCTEventDispatcher.h"
#import "RCTUtils.h"
#import "UIView+React.h"
const NSInteger UNINITIALIZED_INDEX = -1;
@interface RCTPicker() <UIPickerViewDataSource, UIPickerViewDelegate>
@end
@implementation RCTPicker
{
RCTEventDispatcher *_eventDispatcher;
NSArray *_items;
NSInteger _selectedIndex;
}
- (instancetype)initWithEventDispatcher:(RCTEventDispatcher *)eventDispatcher
{
RCTAssertParam(eventDispatcher);
if ((self = [super initWithFrame:CGRectZero])) {
_eventDispatcher = eventDispatcher;
_selectedIndex = UNINITIALIZED_INDEX;
self.delegate = self;
}
return self;
}
RCT_NOT_IMPLEMENTED(-initWithFrame:(CGRect)frame)
RCT_NOT_IMPLEMENTED(-initWithCoder:(NSCoder *)aDecoder)
- (void)setItems:(NSArray *)items
{
_items = [items copy];
[self setNeedsLayout];
}
- (void)setSelectedIndex:(NSInteger)selectedIndex
{
if (_selectedIndex != selectedIndex) {
BOOL animated = _selectedIndex != UNINITIALIZED_INDEX; // Don't animate the initial value
_selectedIndex = selectedIndex;
dispatch_async(dispatch_get_main_queue(), ^{
[self selectRow:selectedIndex inComponent:0 animated:animated];
});
}
}
#pragma mark - UIPickerViewDataSource protocol
- (NSInteger)numberOfComponentsInPickerView:(__unused UIPickerView *)pickerView
{
return 1;
}
- (NSInteger)pickerView:(__unused UIPickerView *)pickerView
numberOfRowsInComponent:(__unused NSInteger)component
{
return _items.count;
}
#pragma mark - UIPickerViewDelegate methods
- (NSDictionary *)itemForRow:(NSInteger)row
{
return _items[row];
}
- (id)valueForRow:(NSInteger)row
{
return [self itemForRow:row][@"value"];
}
- (NSString *)pickerView:(__unused UIPickerView *)pickerView
titleForRow:(NSInteger)row forComponent:(__unused NSInteger)component
{
return [self itemForRow:row][@"label"];
}
- (void)pickerView:(__unused UIPickerView *)pickerView
didSelectRow:(NSInteger)row inComponent:(__unused NSInteger)component
{
_selectedIndex = row;
NSDictionary *event = @{
@"target": self.reactTag,
@"newIndex": @(row),
@"newValue": [self valueForRow:row]
};
[_eventDispatcher sendInputEventWithName:@"change" body:event];
}
@end