Tap Gesture on part of UILabel

问题:

I could successfully add tap gestures to a part of UITextView with the following code:

UITextPosition *pos = textView.endOfDocument;// textView ~ UITextView

for (int i=0;i<words*2-1;i++){// *2 since UITextGranularityWord considers a whitespace to be a word

    UITextPosition *pos2 = [textView.tokenizer positionFromPosition:pos toBoundary:UITextGranularityWord inDirection:UITextLayoutDirectionLeft];
    UITextRange *range = [textView textRangeFromPosition:pos toPosition:pos2];
    CGRect resultFrame = [textView firstRectForRange:(UITextRange *)range ];

    UIView* tapViewOnText = [[UIView alloc] initWithFrame:resultFrame];
    [tapViewOnText addGestureRecognizer:[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(targetRoutine)]];
    tapViewOnText.tag = 125;
    [textView addSubview:tapViewOnText];

    pos=pos2;
}

I wish to imitate the same behaviour in a UILabel. The issue is, UITextInputTokenizer (used to tokenize the individual words) is declared in UITextInput.h, and only UITextView & UITextFieldconform to UITextInput.h; UILabel does not. Is there a workaround for this ??

回答1:

You could try https://github.com/mattt/TTTAttributedLabel and add a link to the label. When the link is pressed you get a action, so part of the label click works only thing you have to would be customizing the link part of the label. I tried this in the past and it worked flawlessly but my client was not interested in using a third party component so duplicated this functionality using UIWebView and HTML.

回答2:

Try this. Let your label be label :

  //add gesture recognizer to label
  UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] init];
  [label addGestureRecognizer:singleTap];
  //setting a text initially to the label
  [label setText:@"hello world i love iphone"];

 - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
 {

UITouch *touch = [touches anyObject];
CGPoint touchPoint = [touch locationInView:self.view];

CGRect rect = label.frame;
CGRect newRect = CGRectMake(rect.origin.x, rect.origin.y, rect.size.width/2, rect.size.height);

if (CGRectContainsPoint(newRect, touchPoint)) {
    NSLog(@"Hello world");
}
}

Clicking on the first half of label will work (It gives log output). Not the other half.

回答3:

Here is a light-weighted library specially for links in UILabel FRHyperLabel.

To achieve an effect like this:

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Pellentesque quis blandit eros, sit amet vehicula justo. Nam at urna neque. Maecenas ac sem eu sem porta dictum nec vel tellus.

use code:

//Step 1: Define a normal attributed string for non-link texts
NSString *string = @"Lorem ipsum dolor sit amet, consectetur adipiscing elit. Pellentesque quis blandit eros, sit amet vehicula justo. Nam at urna neque. Maecenas ac sem eu sem porta dictum nec vel tellus.";
NSDictionary *attributes = @{NSFontAttributeName: [UIFont preferredFontForTextStyle:UIFontTextStyleHeadline]};

label.attributedText = [[NSAttributedString alloc]initWithString:string attributes:attributes];


//Step 2: Define a selection handler block
void(^handler)(FRHyperLabel *label, NSString *substring) = ^(FRHyperLabel *label, NSString *substring){
    NSLog(@"Selected: %@", substring);
};


//Step 3: Add link substrings
[label setLinksForSubstrings:@[@"Lorem", @"Pellentesque", @"blandit", @"Maecenas"] withLinkHandler:handler];

回答4:

One option would be to use a non-editable UITextView instead of a UILabel. Of course this may or may not be a suitable solution depending on your exact needs.

回答5:

This is basic code for how can add UITapGestureRecognizer to your control;

UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleSingleTap:)];        
[MyLabelName addGestureRecognizer:singleTap];        
[self.view addSubView:MyLabelName]

This is method that call when you tapped your MyLabelName;

-(void)handleSingleTap:(UILabel *)myLabel
{
    // do your stuff;
}