根據標籤更改特定命令按鈕的標題

Question

我對Xcode比較陌生，我需要一些幫助。所以，我的觀點有2個按鈕（它有更多的按鈕，但爲了簡單起見，我們假設2）都連接到一個IBAction。當按下每個按鈕時，拾取器會顯示根據按下哪個按鈕加載數組。我希望按鈕的標題與用戶在PickerView中選擇的內容相匹配。

我知道我必須修改pickerView:didSelectRow方法中的一些代碼，但我不知道該怎麼做。現在它的工作方式是，不管我點擊哪個按鈕（我應該注意正確的數組加載，以便該部分正常工作），帶有標籤「0」的按鈕會被選中的Picker行的內容修改。所以我需要修改SELECTED標籤上的按鈕。

我的頭文件是：

@interface XYZSecondViewController : UIViewController <UITextFieldDelegate, UIPickerViewDataSource, UIPickerViewDelegate> 

@property (strong, nonatomic) IBOutlet UIPickerView *myPicker; 
@property (strong, nonatomic) IBOutlet UIButton *myButton; 

- (IBAction)myButton:(id)sender; 

@end 

我實現文件：

#import "XYZSecondViewController.h" 
@interface XYZSecondViewController() 
    @property (strong,nonatomic) NSArray *myArray1; 
    @property (strong,nonatomic) NSArray *myArray2; 
    @property (strong,nonatomic) NSArray *chosenArray; 
@end 

@implementation XYZSecondViewController 
@synthesize myButton, myPicker; 

- (IBAction)myButton:(id)sender 
{ 
    switch ([sender tag]) 
    { 
     case 0: 
      self.chosenArray = self.myArray1; 
      break; 
     case 1: 
      self.chosenArray = self.myArray2; 
      break; 
    } 
    [self.myPicker reloadAllComponents]; 
} 

-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component 
{ 
     return [chosenArray objectAtIndex:row]; 
} 

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent: (NSInteger)component 
{ 
     [myButton setTitle:[chosenArray objectAtIndex:row] forState:UIControlStateNormal]; 
} 

Answer 1

你可以跟蹤目前拍了拍按鈕的標籤。

事情是這樣的：

@property (nonatomic) NSInteger tagLastTappedButton; 

... 

- (IBAction)myButton:(id)sender 
{ 
    tagLastTappedButton = sender.tag; 
    ... 
} 

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent: (NSInteger)component 
{ 
     UIButton *buttonTapped = (UIButton *)[self.view viewWithTag:tagLastTappedButton]; 
    [buttonTapped setTitle:[chosenArray objectAtIndex:row] forState:UIControlStateNormal]; 
} 

Answer 2

拿你一個整數頭：

int flag; 

修改您切換情況：

switch ([sender tag]) 
    { 
     case 0: 
      self.chosenArray = self.myArray1; 
      flag=0; 
      break; 
     case 1: 
      self.chosenArray = self.myArray2; 
      flag=1; 
      break; 
    } 

，並在您didSelectRow作出IF聲明像：

if (flag==0) { 
    [myButton1 setTitle:[chosenArray objectAtIndex:row] forState:UIControlStateNormal]; 
}else{ 
    [myButton2 setTitle:[chosenArray objectAtIndex:row] forState:UIControlStateNormal]; 
}