通字典給選擇

Question

我在想，如果你可以做這樣的事情：

[self.verificationCodeField addTarget:self 
      action:@selector(textFieldDidChange:) 
    forControlEvents:UIControlEventEditingChanged]; 
    [self.verificationCodeField1 addTarget:self 
       action:@selector(textFieldDidChange:) 
     forControlEvents:UIControlEventEditingChanged]; 
    [self.verificationCodeField2 addTarget:self 
       action:@selector(textFieldDidChange:) 
     forControlEvents:UIControlEventEditingChanged]; 
    [self.verificationCodeField3 addTarget:self 
       action:@selector(textFieldDidChange:) 
     forControlEvents:UIControlEventEditingChanged]; 
    [self.verificationCodeField4 addTarget:self 
       action:@selector(textFieldDidChange:) 
     forControlEvents:UIControlEventEditingChanged]; 

以更有效的方式。我嘗試將它們分組爲可變綁定，如下所示：

NSDictionary *dictWithAllTheTextFields = 
NSDictionaryOfVariableBindings(self.verificationCodeField, 
self.verificationCodeField1,self. 
verificationCodeField2, 
self.verificationCodeField3, 
self.verificationCodeField4); 

然後將整個組傳遞給選擇器，但那也不起作用。

也沒有這項工作：

for(UITextField *textField in dictWithAllTheTextFields){ 
    [textField addTarget:self action:@selector(textFieldDidChange:) 
    forControlEvents:UIControlEventEditingChanged]; 
    } 

，這是什麼情況下最有效的方法是什麼？

Answer 1

你並不需要一個字典作爲數組會做：

NSArray *textFields = @[ 
    self.verificationCodeField, 
    self.verificationCodeField1, 
    self.verificationCodeField2, 
    self.verificationCodeField3, 
    self.verificationCodeField4 
]; 

，然後你的代碼將工作：

for (UITextField *textField in textFields) { 
    [textField addTarget:self 
        action:@selector(textFieldDidChange:) 
     forControlEvents:UIControlEventEditingChanged]; 
}