帮助解决iPHone App上的奇怪文本验证问题

Question

我正在使用两种形式的文本验证（一种是他们单击“下一步”时，另一种是当他们手动选择要输入的下一个文本字段时），并且运行良好。 但是，最后一个文本字段没有得到错误检查，我无法弄清楚。

您可以在此视频的最后一个文本字段（ http://screencast.com/t/ODJiOTAwMzA ）上看到问题。 如您所见，前四个工作正常，但最底端的工作不多。

这是我的代码：

- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
    if (textField == txtUserName)
    {
        NSString *userNameOne = txtUserName.text;
        double numOne = [userNameOne doubleValue];  

        if(numOne < 30 || numOne > 80)
        {

            //foo

            [txtUserName becomeFirstResponder];
            txtUserName.text = nil;
        }
        else 
        {
            [txtUserName2 becomeFirstResponder];
        }
    }

    else if (textField == txtUserName2)
    {

        NSString *userNameThree = txtUserName2.text;
        float numTwo = [userNameThree doubleValue]; 

        if (numTwo < 20 || numTwo > 32)
        {
            //foo

            [txtUserName2 becomeFirstResponder];
            txtUserName2.text = nil;
        }
        else
        {
            [txtUserName3 becomeFirstResponder];
        }
    }
    else if (textField == txtUserName3)
    {
        NSString *userNameThree = txtUserName3.text;
        float numThree = [userNameThree doubleValue];

        if (numThree < 475 || numThree > 650)
        {
            //foo

            [txtUserName3 becomeFirstResponder];
            txtUserName3.text = nil;
        }
        else
        {
            [txtUserName4 becomeFirstResponder];

        }
    }
    else if (textField == txtUserName4)
    {
        NSString *userNameFour = txtUserName4.text; 
        double numFour = [userNameFour doubleValue];

        if (numFour < 0.5 || numFour > 3.00)
        {

                        //foo

            [txtUserName4 becomeFirstResponder];
            txtUserName4.text = nil;
        }
        else
        {
            [txtUserName5 becomeFirstResponder];
        }
    }

    else if (textField == txtUserName5)
    {
        NSString *userNameFive = txtUserName5.text;
        double numFive = [userNameFive doubleValue];

        if (numFive > 1)
        {
                        //foo

        }
    }
    return NO;
}

和这里

if (textField == txtUserName)
    {
        NSString *userNameOne = txtUserName.text;
        double numOne = [userNameOne doubleValue];  

        if(numOne < 30 || numOne > 80)
        {

                        //foo

            [txtUserName becomeFirstResponder];
            txtUserName.text = nil;
        }
        else 
        {
            [txtUserName2 becomeFirstResponder];
        }
    }

    else if (textField == txtUserName2)
    {

        NSString *userNameThree = txtUserName2.text;
        float numTwo = [userNameThree doubleValue]; 

        if (numTwo < 20 || numTwo > 32)
        {

                        //foo

            [txtUserName2 becomeFirstResponder];
            txtUserName2.text = nil;
        }
        else
        {
            [txtUserName3 becomeFirstResponder];
        }
    }
    else if (textField == txtUserName3)
    {
        NSString *userNameThree = txtUserName3.text;
        float numThree = [userNameThree doubleValue];

        if (numThree < 475 || numThree > 650)
        {
            //fo

            [txtUserName3 becomeFirstResponder];
            txtUserName3.text = nil;
        }
        else
        {
            [txtUserName4 becomeFirstResponder];

        }
    }
    else if (textField == txtUserName4)
    {
        NSString *userNameFour = txtUserName4.text; 
        double numFour = [userNameFour doubleValue];

        if (numFour < 0.5 || numFour > 3.00)
        {

            //foo

            [txtUserName4 becomeFirstResponder];
            txtUserName4.text = nil;
        }
        else
        {
            [txtUserName5 becomeFirstResponder];
        }
    }
    else if (textField == txtUserName5)
    {
        NSString *userNameFive = txtUserName5.text;
        double numFive = [userNameFive doubleValue];

        if (numFive > 1)
        {
            //foo
        }
        else
        {
            [txtUserName5 becomeFirstResponder];
        }
    }

Answer 1

如果您的界面在Interface Builder中，是否连接txtUserName5的插座？

对于您的第五个文本字段，为什么不像其他文本字段那样在“ foo”之后包含这些行？

if (numFive > 1)
{
    //foo
    [txtUserName5 becomeFirstResponder];
    txtUserName5.text = nil;
}

另外，对于您的else子句，您应该辞职第一响应者（以关闭键盘），而不是再次成为第一响应者：

else
{
    //[txtUserName5 becomeFirstResponder];
    [txtUserName5 resignFirstResponder];
    return YES;
}