Question

我有一些想法，但当然对于第一次使用＆＃34; if条件＆＃34;创建UITextField并不行。我该怎么做？如果UITextField已经存在＆＃34;我可以创建类似＆＃34;的条件吗？ ???

这是我的代码：

-(void)tapDetected:(UIGestureRecognizer*)recognizer{
    NSLog(@"tap detected.");
    CGPoint point = [recognizer locationInView:self.truckImageView];
    UITextField *textField = [[UITextField alloc] initWithFrame:CGRectMake(10, point.y, 300, 40)];
    [textField becomeFirstResponder];
    textField.borderStyle = UITextBorderStyleRoundedRect;
    textField.font = [UIFont systemFontOfSize:24];
    textField.placeholder = @"enter text";
    textField.autocorrectionType = UITextAutocorrectionTypeNo;
    textField.keyboardType = UIKeyboardTypeDefault;
    textField.returnKeyType = UIReturnKeyDone;
    textField.clearButtonMode = UITextFieldViewModeWhileEditing;
    textField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
    textField.delegate = self;
    if (textField.text && textField.text.length > 0)
    {
    [self.view addSubview:textField];
    //    textField.alpha = 0.5;
    [textField setBackgroundColor:[UIColor clearColor]];
    }
    else
    {
        NSLog(@"textField is already created.");
    }
}

Answer 1

不确定。创建UITextField时，您可以指定一个标记：

textField.tag = 1001;

然后在再次创建之前，您可以检查

UITextField *txt = [self.view viewWithTag:1001];
if(txt.tag == 1001)
  return;

Answer 2

我会在头文件中声明一个UITextField，如下所示

@property (strong, nonatomic) UITextField *textField;

然后在tap函数中测试self.textField为null：

if(self.texField == NULL){
    //enter code
}

请记住在代码中将所有textfield替换为self.textfield

如果已创建UITextField，则不要在Tap上重新创建UITextField

2 个答案: