ios - UISegmentedControl 获取之前选择的索引

Question

我有一个带有分段 ValueChanged 方法的分段控件。在调用此方法之前，我需要找出选择的索引是什么。如何做到这一点？

Answer 1

使用这个函数:

@property (nonatomic, assign) NSInteger oldSegmentedIndex;
@property (nonatomic, assign) NSInteger actualSegmentedIndex;
.......

- (void)viewDidLoad
{
    .......
    self.oldSegmentedIndex = -1;
    self.actualSegmentedIndex = self.segmentedControl.selectedSegmentIndex;
    .......
}
.......
- (IBAction)didSegmentedValueChanged:(id)sender
{
    //Do whatever you want
    self.oldSegmentedIndex = self.actualSegmentedIndex;
    self.actualSegmentedIndex = self.segmentedControl.selectedSegmentIndex;
}