I want to implement a same autocomplete email functionality as showing in above screen in my UITextField
Please suggest
Do as follows,
1)store the emails
2)When the user starts type the text in textField search the stored valu and display the values in UITableView
You should use the following delegate of UITextField
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
What kingOfBliss said is the correct way. anyhow i will provide you some logic of the code.
Try tis code
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
for(NSString *particularEmail in arrayContainsAllEmailAddress)
{
NSString *firstLetter = #"";
NSInteger stringlen=[string length];
if(particularEmail.length >= stringlen)
{
firstLetter = [particularEmail substringToIndex:stringlen];
}
if(firstLetter.length > 0)
{
if([string.uppercaseString isEqualToString:firstLetter.uppercaseString])
{
[tableArray addObject:particularEmail];
//tableArray is the array which u will load into the tableview. This contains the emails that matches your search name.
}
}
}
// Add your tableArray into UITableView
}
Related
I want to know the current input character the user just inputted.Comparing the old and the new input string seems to work, but it must be the last thing I'd like to try.Any suggestion? I guess there are some methods in iOS SDK that can do this in a better way.
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
from the UITextFieldDelegate should help you.
It is not only called for replacing text, also whenever the user presses a key on keyboard.
(length of range will be 0 then and the location will be the current insertation position).
See the documentation for more information:
http://developer.apple.com/library/ios/#documentation/uikit/reference/UITextFieldDelegate_Protocol/UITextFieldDelegate/UITextFieldDelegate.html#//apple_ref/doc/uid/TP40006991-CH3-SW9
If you want to compare the strings as the characters come in, your better off using
[textField addTarget:self action:#selector(compareInput) forControlEvents:UIControlEventEditingChanged];
-(void)compareInput
{
if ([textField.text isEqualToString:compareString])
NSLog(#"They're the same!");
}
than the delegate:
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
If you literally just want to compare characters, then the delegate method is fine. The variable string contains the typed character.
For example, this is what happens with the above methods when a user types foo into the UITextField:
User types: f, this happens:
[textField addTarget:self action:#selector(compareInput) forControlEvents:UIControlEventEditingChanged];
calls compareInput immediately, and the letter f is available via textField.text:
-(void)compareInput
{
NSLog(textField.text); //prints `f`
}
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
NSLog(textField.text); //prints nothing
return YES;
//after returning YES, textField.text will contain `f`
}
User types: o, this happens:
[textField addTarget:self action:#selector(compareInput) forControlEvents:UIControlEventEditingChanged];
calls compareInput immediately, and the string fo is available via textField.text:
-(void)compareInput
{
NSLog(textField.text); //prints `fo`
}
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
NSLog(textField.text); //prints `f`
return YES;
//after returning YES, textField.text will contain `fo`
}
I'm probably not very clear, but I hope it gives you some insight!
This method will show current input in UITextField
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
NSString *letters;
if ([textField.text isEqualToString:#""]){
letters = string;
}else if ([string isEqualToString:#""]){
if ([textField.text length] > 0) {
letters = [textField.text substringToIndex:[textField.text length] - 1];
}
}else{
letters = [textField.text stringByAppendingString:string];
}
NSLog(#"letters %#\n", letters);
return YES;
}
I'm writing application in which I need to validate text entered by user to UITextField, char by char with some method.
The difficult thing is that client wants to do all the validation before user see character in the UITextField because there might be situation that his server application doesn't support '$' sign, so in my validation method I should replace it with 'USD' string - and he doesn't want user to see '$', just 'USD' immediately.
I know about events like UIControlEventEditingChanged etc., but still, I don't know 2 things:
how to access character typed by user before it's seen in UITextField and execute validation there
how to subtitute this character 'on the fly' and put it manually to UITextField (but I suppose I'll just append this to [[textField] text] NSString
Thank You in advance for any help :)
Implement the UITextFieldDelegate method textField:shouldChangeCharactersInRange:replacementString:, e.g.:
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
BOOL validated = ...; //do your validation
return validated;
}
Similar to omz's answer but more complete code if you need:
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
NSString *filtered;
filtered = [string stringByReplacingOccurrencesOfString:#"$" withString:#"USD"];
//optionally if you want to only have alphanumeric characters
//NSMutableCharacterSet *mcs1 = [[[NSCharacterSet letterCharacterSet] invertedSet] mutableCopy]; //only alphabet character
//[mcs1 removeCharactersInString:#"0123456789"];
//filtered = [[filtered componentsSeparatedByCharactersInSet:mcs1] componentsJoinedByString:#""];
//release mcs1;
return [string isEqualToString:filtered];
}
I want to have the user type in something. And I want to verify each character inputed. How could I do this? I want it to be in real time. So as its typed its being verified and color coded.
You could compare what I want to do to an programmers IDE how it checks the syntax as you type it.
Any help is appreciated!
Connect the UITextField delegate to the app delegate and do something like:
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
if([string isEqual:#"b"]) {
// User typed 'b'
// Insert string with specific color
// [...]
} else {
// User typed something else
// Insert string without specific color
textField.text = [textField.text stringByReplacingCharactersInRange:range withString:string];
}
return YES;
}
i want to let the user type in the name of a new file, so there are certain characters i want to prevent entry on. is there a special keyboard i can use or can i disable certain keys on the iphones keyboard.
is the answer to just run a regular expression on the input text and tell the user the filename is invalid (if so what would that regular expression be?)
ANSWER: (or what i ended up doing)
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{
BOOL valid;
//if the user has put in a space at the beginning
if ([string isEqualToString:#" "]){
if (range.location == 0){
valid = NO;
}
else{
valid = YES;
}
}
//otherwise test for alpha numeric
else{
NSCharacterSet *alphaSet = [NSCharacterSet alphanumericCharacterSet];
valid = [[string stringByTrimmingCharactersInSet:alphaSet] isEqualToString:#""];
}
//print the warning label
if (valid == NO){
[errorLabel setText:#"Invalid input"];
}
else{
[errorLabel setText:nil];
}
return valid;
}
You can implement the delegate method
For UITextField,
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string; // return NO to not change text
For UITextview
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text;
and decide weather to append the entered characters or not.
You can implement the UITextFieldDelegate protocol and use textField:shouldChangeCharactersInRange:replacementString: to watch the text entry and prevent unwanted characters by returning NO.
I have a UITextField in my application. I'd like to restrict the set of characters that can be can be entered into the field to a set that I have defined. I could filter the characters entered into the field when the text is committed using the UITextFieldDelegate method:
- (BOOL)textFieldShouldReturn:(UITextField*)textField
However, this gives the user a false impression as although restricted characters are removed from the final value, they were still visibly entered into the text field before pressing Return/Done/etc. What is the best approach that would prevent restricted characters appearing in the text field as they are selected on the keyboard?
Note: I am operating under the assumption that I have little control over which keys are provided by the iPhone keyboard(s). I am aware that I can switch between various keyboard implementations but am under the impression that I can't disable specific keys. This assumption may be incorrect.
I did as marcc suggested and it worked well. Sample implementation follows.
Note: Variable names were selected for brevity and do not reflect my coding standards:
...
myCharSet = [NSCharacterSet characterSetWithCharactersInString:#"xyzXYZ"];
...
}
- (BOOL) textField:(UITextField*)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString*)textEntered {
for (int i = 0; i < [textEntered length]; i++) {
unichar c = [textEntered characterAtIndex:i];
if (![myCharSet characterIsMember:c]) {
return NO;
}
}
return YES;
}
Look at textField:shouldChangeCharactersInRange
This method is called by the UITextFieldDelegate whenever new characters are typed or existing characters are deleted from the text field. You could return NO to not allow the change.
Here is one of the cleanest approaches to restricting characters entered in a UITextField. This approach allows the use of multiple predefined NSCharacterSets.
-(BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{
NSMutableCharacterSet *allowedCharacters = [NSMutableCharacterSet alphanumericCharacterSet];
[allowedCharacters formUnionWithCharacterSet:[NSCharacterSet whitespaceCharacterSet]];
[allowedCharacters formUnionWithCharacterSet:[NSCharacterSet symbolCharacterSet]];
if([string rangeOfCharacterFromSet:allowedCharacters.invertedSet].location == NSNotFound){
return YES;
}
return NO;
}
Look at the UITextViewDelegate method - (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string.
It's exactly what you need.
This is what I use to restrict the user to uppercase A-Z. Adjust the regex variable according to taste:
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
NSString* regex = #"[^A-Z]";
return ([string rangeOfString: regex
options:NSRegularExpressionSearch].location == NSNotFound);
};
How about this?
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
NSString* regex = #"[^a-z]";
return ([[string lowercaseString] rangeOfString: regex
options:NSRegularExpressionSearch].location == NSNotFound);
};
Note:
I am making all characters to lower case [string lowercaseString] so that you don't need to write in regex for captial/small letters.
You could loop and keep checking if the UITextField.text property has changed once the DidBeginEditing method gets called. If it has, check the text and remove an bad characters.