I'm using a UITextView to display some text. In laying out the text, I enumerate the lines of text using the enumerateLineFragmentsForGlyphRange:withBlock: method.
NSInteger shrunkNumberOfLines = 3;
__block NSMutableString *shortenedText = [NSMutableString new];
__block NSInteger currentLine = 0;
__block BOOL needsTruncation = NO;
[detailsTableViewCell.descriptionTextView.layoutManager enumerateLineFragmentsForGlyphRange:NSMakeRange(0, text.length) usingBlock:^(CGRect rect, CGRect usedRect, NSTextContainer *textContainer, NSRange glyphRange, BOOL *stop) {
if (currentLine < shrunkNumberOfLines) {
NSRange stringRange = ((glyphRange.length + glyphRange.location) <= text.length) ? glyphRange : NSMakeRange(glyphRange.location, (text.length - glyphRange.location));
NSString *appendString = [text substringWithRange:stringRange];
NSLog(#"%#", appendString);
[shortenedText appendString:appendString];
currentLine += 1;
} else {
needsTruncation = YES;
*stop = YES;
}
}];
However, I'm running into a weird bug: oftentimes, the text that gets displayed in the textview doesn't line up with the text that I see in that appendString.
For example, the text in the textfield might say something like:
President Obama offered a
blueprint for deeper American
engagement in the Middle East.
...but looking at my NSLog statements, those appendStrings are something like:
President Obama offered a blu
eprint for deeper American en
gagement in the Middle East.
I've tried a bunch of things - playing with hyphenationFactor, making sure that the textContainerInsets are correct, etc - but I can't figure this out. What's causing invalid line breaks in the enumerateLineFragmentsForGlyphRange:withBlock: method?
While I'm still not sure what caused the underlying issue above, I've at least found something that solves the symptom: https://stackoverflow.com/a/19603172/686902
I need to achieve something exactly like NSLineBreakByTruncatingHead for UITextField as shown here. Let's assume the original text is:
This is the long text that cannot be shown inside a UITextField
I need it like:
...cannot be shown inside a UITextField
but currently I am getting something like:
This is the long text that cannot...
simply the truncation at the beginning. The lineBreakMode property is not given for UITextField. How can I achieve it?
I took the solution here and modified it to truncate the head of a string instead of the tail. Know that it only shows the ellipsis when the field is not being edited.
NOTE: This solution is for iOS 7+ only. To use in iOS 6, use sizeWithFont: instead of sizeWithAttributes: in the NSString+TruncateToWidth.m file.
EDIT: Added support for iOS 6
NSString+TruncateToWidth.h
#interface NSString (TruncateToWidth)
- (NSString*)stringByTruncatingToWidth:(CGFloat)width withFont:(UIFont *)font;
#end
NSString+TruncateToWidth.m
#import "NSString+TruncateToWidth.h"
#define ellipsis #"…"
#implementation NSString (TruncateToWidth)
- (NSString*)stringByTruncatingToWidth:(CGFloat)width withFont:(UIFont *)font
{
// Create copy that will be the returned result
NSMutableString *truncatedString = [self mutableCopy];
// Make sure string is longer than requested width
if ([self widthWithFont:font] > width)
{
// Accommodate for ellipsis we'll tack on the beginning
width -= [ellipsis widthWithFont:font];
// Get range for first character in string
NSRange range = {0, 1};
// Loop, deleting characters until string fits within width
while ([truncatedString widthWithFont:font] > width)
{
// Delete character at beginning
[truncatedString deleteCharactersInRange:range];
}
// Append ellipsis
[truncatedString replaceCharactersInRange:NSMakeRange(0, 0) withString:ellipsis];
}
return truncatedString;
}
- (CGFloat)widthWithFont:(UIFont *)font
{
if([self respondsToSelector:#selector(sizeWithAttributes:)])
return [self sizeWithAttributes:#{NSFontAttributeName:font}].width;
return [self sizeWithFont:font].width;
}
Using it:
...
// Make sure to import the header file where you want to use it
// assumes instance variable holds your string that populates the field
fieldString = #"abcdefghijklmnopqrstuvwxyz1234567890";
// Size will need to be less than text field's width to account for padding
_myTextField.text = [fieldString stringByTruncatingToWidth:(_myTextField.frame.size.width - 15) withFont:_myTextField.font];
...
// use textFieldShouldBeginEditing to make it animate from the start of the field to the end of the string if you prefer that. I found it a little distracting
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
textField.text = fieldString;
}
- (BOOL)textFieldShouldEndEditing:(UITextField *)textField
{
fieldString = textField.text;
textField.text = [textField.text stringByTruncatingToWidth:(textField.frame.size.width - 15) withFont:textField.font];
return YES;
}
I had a similar requirement, I wrote a Swift version of #Stonz2 solution, it worked most of the times, havent used in production yet as the requirement was removed later... anyways posting it here
extension String {
func stringByTruncatingLeadingForWidth(width: CGFloat, withFont font: UIFont) -> String{
var modifiedString = self
var mutableWidth = width
let ellipsis = "..."
if (self.widthOfString(usingFont: font) > width) {
let ellipsisWidth = ellipsis.widthOfString(usingFont: font)
// else this will go for infinite loop...mutable width will go -ve
if mutableWidth > ellipsisWidth {
mutableWidth -= ellipsis.widthOfString(usingFont: font)
}
let range = NSMakeRange(0, 1)
while modifiedString.widthOfString(usingFont: font) > mutableWidth {
modifiedString.deleteCharactersInRange(range: range)
print(modifiedString)
print(mutableWidth)
}
guard let swiftRange = Range(NSMakeRange(0, 3), in: modifiedString) else { return "" }
modifiedString.replaceSubrange(swiftRange, with: [".",".","."])
}
return modifiedString
}
func widthOfString(usingFont font: UIFont) -> CGFloat {
let fontAttributes = [NSAttributedString.Key.font: font]
let size = self.size(withAttributes: fontAttributes)
return size.width
}
mutating func deleteCharactersInRange(range: NSRange) {
guard let swiftRange = Range(range, in: self) else { return }
self.removeSubrange(swiftRange)
}
}
var str1 = "Hello how are you"
let newStr = str1.stringByTruncatingLeadingForWidth(width: 100, withFont: .systemFont(ofSize: 15))
I want to add a string in the highlighted area in the textview, I mean by the highlighted area, where the blue line is located.
So once the user click on the button it adds a string where the "blue line" is located
I used stringByAppendingString but it adds the string after the word exists only
NSRange range = myTextView.selectedRange;
NSString * firstHalfString = [myTextView.text substringToIndex:range.location];
NSString * secondHalfString = [myTextView.text substringFromIndex: range.location];
myTextView.scrollEnabled = NO; // turn off scrolling
NSString * insertingString = [NSString stringWithFormat:#"your string value here"];
myTextView.text = [NSString stringWithFormat: #"%#%#%#",
firstHalfString,
insertingString,
secondHalfString];
range.location += [insertingString length];
myTextView.selectedRange = range;
myTextView.scrollEnabled = YES;
You need to use the selectedRange to find out where the text cursor is. Then use replaceCharactersInRange:withString: or insertString:atIndex: to insert the new text into the original text. Then update the text into the view.
Even though its not clear what you are trying to achieve, it seems that you want the user to start editing the textfield from the position where text starts. In that case , you can refer following:
Hint 1
Set your view controller (or some other appropriate object) as the text field's delegate and implement the textFieldDidBeginEditing: method like this:
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
UITextPosition *beginning = [textField beginningOfDocument];
[textField setSelectedTextRange:[textField textRangeFromPosition:beginning
toPosition:beginning]];
}
Note that setSelectedTextRange: is a protocol method of UITextInput (which UITextField implements), so you won't find it directly in the UITextField documentation.
Hint 2
self.selectedTextRange = [self textRangeFromPosition:newPos toPosition:newPos];
Hint 3
finding-the-cursor-position-in-a-uitextfield/
Question
Is there any way to "accurately" limit the number of line in UITextView for target iOS 5.0?
What I had tried
As I had search in stack overflow. I had found these question been ask before in links below.
In UITextView, how to get the point that next input will begin another line
Limit the number of lines for UITextview
Limit number of lines in UITextView
But I still can't get the accurate number of line in UITextView when I tried to decide whether to return YES or NO in textView:shouldChangeTextInRange:replacementText:.
I had tried used the code which is the answer of Limiting text in a UITextView and the code after modified (remove -15 in the answer) is showing below.
- (BOOL)textView:(UITextView *)aTextView shouldChangeTextInRange:(NSRange)aRange replacementText:(NSString*)aText
{
NSString* newText = [aTextView.text stringByReplacingCharactersInRange:aRange withString:aText];
// TODO - find out why the size of the string is smaller than the actual width, so that you get extra, wrapped characters unless you take something off
CGSize tallerSize = CGSizeMake(aTextView.frame.size.width,aTextView.frame.size.height*2); // pretend there's more vertical space to get that extra line to check on
CGSize newSize = [newText sizeWithFont:aTextView.font constrainedToSize:tallerSize lineBreakMode:UILineBreakModeWordWrap];
if (newSize.height > aTextView.frame.size.height)
{
[myAppDelegate beep];
return NO;
}
else
return YES;
}
I also figure out a way to get the number of line in UITextView. The way is to calculate by contentSize property like textView.contenSize.height/font.lineHeight. This method can get the accurate number of lines in UITextView. But the problem is that contentSize get in textView:shouldChangeTextInRange:replacementText: and textViewDidChange: is the old contentSize. So I still can't limit the number of lines in UITextView.
Solution I used
This is kind of workaround but at least it work.
Step 1
At first you need to create a temporary new UITextView with all the same as the original UITextView but setting the temporary UITextView hidden in .xib file. In this sample code I name the temporary UITextView as tempTextInputView
Step 2
Add new referencing outlet to .h file like
#property (retain, nonatomic) IBOutlet UITextView *tempTextInputView;// Use to calculate the number of lines in UITextView with new text
Step 3
Add code below.
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text{
NSString *newText = [textView.text stringByReplacingCharactersInRange:range withString:text];
_tempTextInputView.text = newText;
// Calcualte the number of lines with new text in temporary UITextView
CGRect endRectWithNewText = [_tempTextInputView caretRectForPosition:_tempTextInputView.endOfDocument];
CGRect beginRectWithNewText = [_tempTextInputView caretRectForPosition:_tempTextInputView.beginningOfDocument];
float beginOriginY = beginRectWithNewText.origin.y;
float endOriginY = endRectWithNewText.origin.y;
int numberOfLines = (endOriginY - beginOriginY)/textView.font.lineHeight + 1;
if (numberOfLines > maxLinesInTextView) {// Too many lines
return NO;
}else{// Number of lines will not over the limit
return YES;
}
}
Discussion
maxLinesInTextView is an int variable represent the maximum number of lines you want.
I use a temporary UITextView to setting new text is because when I setting the new text simply in the original UITextView, I got some problem when I typing in ChuYin(注音) keyboard which is a Traditional Chinese input method.
I still using textView:shouldChangeTextInRange:replacementText: but not textViewDidChange: is because I got some problem when cache the text before modify with a global NSString and replace the UITextView.text with that global NSString in textViewDidChange:.
Here's how you can use the UITextViewDelegate shouldChangeTextInRange: method to limit the text entry to the height of the text view:
func textView(textView: UITextView, shouldChangeTextInRange range: NSRange, replacementText text: String) -> Bool {
// Combine the new text with the old
let combinedText = (textView.text as NSString).stringByReplacingCharactersInRange(range, withString: text)
// Create attributed version of the text
let attributedText = NSMutableAttributedString(string: combinedText)
attributedText.addAttribute(NSFontAttributeName, value: textView.font, range: NSMakeRange(0, attributedText.length))
// Get the padding of the text container
let padding = textView.textContainer.lineFragmentPadding
// Create a bounding rect size by subtracting the padding
// from both sides and allowing for unlimited length
let boundingSize = CGSizeMake(textView.frame.size.width - padding * 2, CGFloat.max)
// Get the bounding rect of the attributed text in the
// given frame
let boundingRect = attributedText.boundingRectWithSize(boundingSize, options: NSStringDrawingOptions.UsesLineFragmentOrigin, context: nil)
// Compare the boundingRect plus the top and bottom padding
// to the text view height; if the new bounding height would be
// less than or equal to the text view height, append the text
if (boundingRect.size.height + padding * 2 <= textView.frame.size.height){
return true
}
else {
return false
}
}
As I have mentioned in my answer here, I advise against using shouldChangeCharactersInRange: since it is invoked before the text is actually changed.
Using the textViewDidChangeMethod: makes more sense, since it is invoked after the text actually changes. From there you can easily decide what to do next.
One options is to modify the textView yourself in the shouldChangeTextInRange delegate method and always return NO (because you already did the work for it).
- (BOOL)textView:(UITextView *)aTextView shouldChangeTextInRange:(NSRange)aRange replacementText:(NSString*)aText
{
NSString* oldText = aTextView.text;
NSString* newText = [aTextView.text stringByReplacingCharactersInRange:aRange withString:aText];
aTextView.text = newText;
if(/*aTextView contentSize check herer for number of lines*/)
{
//If it's now too big
aTextView.text = oldText;
}
return NO
}
I have a button that toggles between Show/Hide mode (i.e. toggles a UITextField between secureTextEntry NO and YES). The purpose of which is to allow the user to see the password they are entering.
I followed the example (with the highest number of votes) here: UITextField secureTextEntry - works going from YES to NO, but changing back to YES has no effect
However, when I set secureTextEntry to NO, any text that was written there ends up with a space at the end. This does not seem to be a problem when setting secureTextEntry to YES.
For example, if I enter the text "mypassword" while setSecureTextEntry is set to NO, and then switch it to YES, the user will see ********** (10 dots), which is correct. If I setSecureTextEntry to NO, the user will see "mypassword " (with a space at the end, or at least, the cursor moved one space to the right).
Important note: In the debugger, the string value of text appears without the trailing space, like this:
(lldb) expr self.passwordText.text
(NSString *) $0 = 0x1d8450e0 #"mypassword"
I have tried trimming whitespace (per avoid middle whitespace in UITextField), but it has had no effect.
i've just encounter this case and finally solved this problem.
works on Latest iOS SDK, iOS 8.1
First of all, there is no trailing space at all.
The dot(shown in SecureEntry) character and normal character have different width and after you toggle isSecureEntry switch, the cursor didn't refresh it's position.
so i use this workaround to solved this problem.
- (void)toggle
{
NSString *tmpString;
[self.passwordTextField setSecureTextEntry:!self.passwordTextField.isSecureTextEntry];
if (self.passwordTextField.isSecureTextEntry) {
// do stuffs
} else {
// do other stuffs
}
// Workaround to refresh cursor
tmpString = self.passwordTextField.text;
self.passwordTextField.text = #" ";
self.passwordTextField.text = tmpString;
}
Swift 3+
// Workaround to refresh cursor
let currentText: String = self.userPassword.text!
self.userPassword.text = "";
self.userPassword.text = currentText
hope it helps!
PRE-iOS-8.0 (dated solution)... In your button's action method (toggling between secureTextEntry YES and NO), simply set UITextField's text property to its current text value. Although this may seem redundant and a bit like a hack, this will redraw the cursor in the right position. Here's an example of what your button's action method should look like now...
-(void)toggleButtonPressed:(UIButton*)sender
{
// Toggle between secure and not-so-secure entry
self.toggleButton.selected = !self.toggleButton.selected;
self.textfield.secureTextEntry = !self.toggleButton.selected;
// * Redundant (but necessary) line *
[self.textfield setText:self.textfield.text];
}
POST-iOS-8.0... As of iOS 8.0, it appears that UITextField's text setter no longer redraws the cursor when called with a string equal to its current string value. Now, we need to take this a step further and actually change the text value before resetting it again. Replace the above setText: line with something like these lines.
// * Extra redundant (but necessary) lines *
NSString *currentText = self.textfield.text;
[self.textfield setText:#"Arbitrary string..."]; // Change the value
[self.textfield setText:currentText]; // Reset the value
I have a clean solution not going dirty with text property of UITextField.
Wrap them in this style.
[self.passwordTextField resignFirstResponder]; // first resign its first responder.
// change `secureTextEntry` property's value if necessary.
if (self.passwordTextField.secureTextEntry) {
self.passwordTextField.secureTextEntry = NO;
self.passwordEcryptButton.selected = YES;
}else{
self.passwordTextField.secureTextEntry = YES;
self.passwordEcryptButton.selected = NO;
}
[self.passwordTextField becomeFirstResponder]; // finally gain its first responder again.
In order to work around this bug in iOS you can simply do the following (works for any iOS version):
- (IBAction)toggleSecureTextEntry:(UIButton *)button
{
self.textField.secureTextEntry = !self.textField.secureTextEntry;
NSString *originalText = self.textField.text;
self.textField.text = nil;
self.textField.text = originalText;
}
You can fix it like this:
NSString *currentText = self.textfield.text;
self.textfield.text = #"";
self.textfield.text = currentText;
This work for me on iOS 8
if (self.passwordTextField.secureTextEntry) {
// Display password and keep selected text range
UITextRange *selectedTextRange = self.passwordTextField.selectedTextRange;
NSString *password = self.passwordTextField.text;
self.passwordTextField.secureTextEntry = NO;
self.passwordTextField.text = [#"" stringByPaddingToLength:password.length withString:#" " startingAtIndex:0]; // Done for carret redrawing
self.passwordTextField.text = password;
self.passwordTextField.selectedTextRange = selectedTextRange;
}
else {
// Hide password and keep selected text range
UITextRange *selectedTextRange = self.passwordTextField.selectedTextRange;
NSString *password = self.passwordTextField.text;
self.passwordTextField.secureTextEntry = YES;
self.passwordTextField.text = [#"" stringByPaddingToLength:password.length withString:#" " startingAtIndex:0]; // Done for carret redrawing
self.passwordTextField.text = password;
self.passwordTextField.selectedTextRange = selectedTextRange;
}
UITextPosition *beginning = [self.passwordField beginningOfDocument];
[self.passwordField setSelectedTextRange:[self.passwordField textRangeFromPosition:beginning
toPosition:beginning]];
UITextPosition *end = [self.passwordField endOfDocument];
[self.passwordField setSelectedTextRange:[self.passwordField textRangeFromPosition:end
toPosition:end]];
This is what I used for iOS 8
When we change a textfield.secureTextEntry property, the caret position is not updated. To fix this, the code below used to work before IOS 8:
pwdTextField.text = pwdTextField.text
Now it doesn't. It seems IOS 8 detects the new value equals old value and does nothing. So to make it work again we have to actually change the value. Here is the swift version that works for me.
let str = pwdTextField.text
pwdTextField.text = str + " "
pwdTextField.text = str
This is another possibility to solve this issue, where self.passwordText is the UITextField:
if (self.passwordText.isFirstResponder) {
[self.passwordText resignFirstResponder];
[self.passwordText becomeFirstResponder];
}
It appears that the second solution in the referenced link, when implemented, has the desired behavior of not adding an extra space:
https://stackoverflow.com/a/8495888/738190
This Works in my case
BOOL wasFirstResponder = [self.passwordTextField isFirstResponder];
if([self.passwordTextField isSecureTextEntry])
{
//This three lines are key
self.passwordTextField.delegate = nil;
[self.passwordTextField resignFirstResponder];
self.passwordTextField.delegate = self;
}
[self.passwordTextField setSecureTextEntry: !self.passwordTextField.isSecureTextEntry];
if(wasFirstResponder)
[self.passwordTextField becomeFirstResponder];
Swift UITextField extension:
extension UITextField {
func toggleSecureEntry() {
let wasFirstResponder = isFirstResponder
if wasFirstResponder { resignFirstResponder() }
isSecureTextEntry.toggle()
if wasFirstResponder { becomeFirstResponder() }
}
}
Setting textField.text solution also works in some situations but not for my need (Custom font with two text fields. Caused font changes and glitches on runtime.) Adding here too.
func toggleSecureEntry() {
isSecureTextEntry.toggle()
let originalText = text
text = nil
text = originalText
}
To get the cursor to reposition correctly, setting the font attributes seemed to do the trick for me.
// Hack to update cursor position
self.passwordTf.defaultTextAttributes = #{NSFontAttributeName: textFieldFont, NSForegroundColorAttributeName: textFieldColor};
// Change secure entry
self.passwordTf.secureTextEntry = !self.passwordTf.secureTextEntry;
Tested on iOS8, iOS9.
Hope it helps!
Everytime the text is set in the UITextField, the cursor postition is updated
So I used this code
partial void btnShowPassword_ToutchUpInside (UIButton sender)
{
if (TxtPassword.SecureTextEntry == true) {
TxtPassword.SecureTextEntry = false;
TxtPassword.Text = TxtPassword.Text;
} else {
TxtPassword.SecureTextEntry = true;
}
}
Here is the solution:
- (void)showHidePassword:(UIButton *)sender {
EDSignUpCell *cell = [self.signUpTblView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:3 inSection:0]];
if(!TRIM_SPACE(cell.cellTextField.text).length) {return;}
[cell.showHidePasswordBtn setSelected:!cell.showHidePasswordBtn.isSelected];
cell.cellTextField.secureTextEntry = cell.showHidePasswordBtn.isSelected;
[cell.cellTextField setText:cell.cellTextField.text];
[cell.cellTextField becomeFirstResponder];
}
I'm using this, Works fine.
[self.yourTextField becomeFirstResponder];
Swift 4
Bug is on radar, there is explanation of workaround also: http://www.openradar.me/38465011
Here is cut of temporary workaround how to natively update caret (cursor) position.
// update caret position
DispatchQueue.main.asyncAfter(deadline: .now() + 0.01) {
let (beginning, end) = (self.beginningOfDocument, self.endOfDocument)
self.selectedTextRange = self.textRange(from: beginning, to: end)
self.selectedTextRange = self.textRange(from: end, to: end)
}
I had a similar issue and realized it was because I was updating the text before setting the secureTextEntry property. It makes sense that the textField would draw out the caret at the location it'd be at if it were using secureTextEntry.
I did not read the entire problem nor did I visit the solution linked by OP, but in case someone else has the same issue as me:
Try updating your text after setting the secureTextEntry property.