iphone - 如何检查文本是否归档值并显示警报并清空iphone中的文本字段

Question

我正在输入值 textfiled 我希望如果它是正确的值那么它可以显示警报并使文本字段为空。所以用户可以输入正确的值我已经尝试了很多方法但我没有解决它。

  -(void)textFieldTextDidChangeClinicMarkup:(UITextField*)tf{

   NSString*test=clinicMarkupTextField.text;



if([test isEqualToString:@"1"]){
    NSString*value=@"1";

    appDelegate.clinicalMarkup=value;


}

else if([test isEqualToString:@"1.5"]){

    NSString*value=@"1.5";

    appDelegate.clinicalMarkup=value;


}


else if([test isEqualToString:@"2"]){

    NSString*value=@"2";

    appDelegate.clinicalMarkup=value;


}


else if([test isEqualToString:@"2.5"]){

    NSString*value=@"2.5";

    appDelegate.clinicalMarkup=value;


}


else if([test isEqualToString:@"3"]){

    NSString*value=@"3";

    appDelegate.clinicalMarkup=value;


}

else if([test length] >=3 || [test floatValue] > 3 || [test floatValue] <1 )  {

    UIAlertView * alert = [[UIAlertView alloc] initWithTitle:@"Warning" message:@"Clinic Markup can only be 1, 1.5, 2, 2.5 and 3 " delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
    [alert show];
    [alert release];

     }
  }

Answer 1

对于这个特定的问题，我会使用一个UIStepper控件来代替：

stepper.minimumValue = 1.0f;
stepper.maximumValue = 3.0f;
stepper.stepValue = 0.5f;

步进控件如下所示：

Answer 2

@james 如果您只有一个文本字段，那么您可以实现以下代码：

- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
 NSString *strText=textField.text;
    if ([strText isEqualToString:@"1"]||[strText isEqualToString:@"1.5"]||[strText isEqualToString:@"2"]||[strText isEqualToString:@"2.5"]||[strText isEqualToString:@"3"]) 
    {
        appDelegate.clinicalMarkup=strText;
        [textField resignFirstResponder];
    }
    else
    {
        UIAlertView * alert = [[UIAlertView alloc] initWithTitle:@"Warning" message:@"Clinic Markup can only be 1, 1.5, 2, 2.5 and 3 " delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
        [alert show];
        [alert release];

    }
return YES;
}

Answer 3

设置您的委托

clinicMarkupTextField.delegate = self;
clinicMarkupTextField.returnKeyType = UIReturnKeyDone;

并尝试下面的代码

-(BOOL)textFieldShouldReturn:(UITextField *)textField{

    if(clinicMarkupTextField == textField) //only if u have more then 1 text field
    {
        NSString*test=textField.text;

    if([test isEqualToString:@"1"]){
            NSString*value=@"1";
        appDelegate.clinicalMarkup=value;
     }

         ---SNIP---             

        else if([test length] >=3 || [test floatValue] > 3 || [test floatValue] <1 )  {

         //if all condition fails 
         textField.text = @"";

             UIAlertView * alert = [[UIAlertView alloc] initWithTitle:@"Warning" message:@"Clinic Markup can only be 1, 1.5, 2, 2.5 and 3 " delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil];
             [alert show];
             [alert release];

          }
       }
 return yes;

    }