How to get the coordinates for the selected text in UIWebView?

Question

I have simple UIWebView with loaded html file. I want to show the PopOverController pointed to the selected text like -

enter image description here .

I want the coordinates of selected text from UIWebView. If I set the scalesPageToFit property of UIWebView to NO, then this link works fine. If I set the scalesPageToFit property of UIWebView to YES, then it fails.

Anyone please help me to sort out my problem.

@virantporwal I have edited my question for better understanding. — Girish, Oct 18 '13 at 12:39
OK,then you can try TapUIGestureRecognizer for getting the particulate coordinates. — virantporwal, Oct 18 '13 at 12:50
Why is it that you want the coordinates? I think you can add your own item to the default popup. (I did it in a project a few years ago) — Mike M, Oct 18 '13 at 13:16
@MikeM I want to show the popup from the selected text. I have shown the custom items in popup the issue is related to the positioning of the popup. — Girish, Oct 18 '13 at 13:20

nr5 · Accepted Answer · 2013-10-21T09:52:43.413

1

First of all remove the native long press gesture recogniser like this:

for(UIGestureRecognizer *gesRecog in yourWebView.gestureRecognizers)
    {
        if([gesRecog isKindOfClass:[UILongPressGestureRecognizer class]])
        {
            [startTF removeGestureRecognizer:gesRecog];
        }
    }

Then assign a custom one:

    UILongPressGestureRecognizer *myOwnLongPressRecog = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(handleWebViewLongpress:)];

        // set numberOfTapsRequired and numberOfTouchesRequired as per your requirement:       

[yourWebView addGestureRecognizer:myOwnLongPressRecog];

// Handle Long press like this:

 - (void) handleWebViewLongpress: (UIGestureRecognizer *) recog
    {
     int zoomedWidth = [[yourWebView stringByEvaluatingJavaScriptFromString:@"window.innerWidth"] intValue];

        CGFloat scale = yourWebView.frame.size.width / zoomedWidth;  // get the scaled value of your web view

        CGPoint zoomedCords = [gesture locationInView:self.webView];

        zoomedCords.x /= scale; // Normal math. Divide by the scale to get the real thing.
        zoomedCords.y /= scale;

NSLog(@"%@", zoomedCords);

            }

edited Oct 21 '13 at 09:52

answered Oct 19 '13 at 05:19

nr5

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I already tried with this but it returns wrong y coordinates due to the scalesPageToFit property. – Girish Oct 21 '13 at 05:14
change your Y coordinate as scaling happens. – nr5 Oct 21 '13 at 07:13
1

how can I change the Y-coordinate? User can select any text from the UIWebView. – Girish Oct 21 '13 at 08:31
You have to get the scaled value. Like when you zoom an image and want to get where the user actually tapped. Check my updated Answer. – nr5 Oct 21 '13 at 09:53
you said before, it was not working. What was the wrong before?? JUst in case I encounter the same problem... – nr5 Oct 28 '13 at 06:58
I didn't set the delegate to the longpress gesture so it does not called its delegate method & not getting the correct output. I set the delegate & it works well. thanks – Girish Oct 28 '13 at 14:04

score 1 · Answer 2 · answered Oct 27 '13 at 15:40

This must be be accomplished almost completely within JavaScript and then have the result passed back into Objective C. If you have control of the content you are showing, you can add this function into a <script> tag. Otherwise you will need to inject it as described in this post.

function rectsForSelection() {
    var i = 0, j = 0;
    var allSelections = window.getSelection();
    var result = []; // An empty array right now
    // Generally, there is only one selection, but the spec allows multiple
    for (i=0; i < allSelections.rangeCount; i++) {
        var aRange = allSelections.getRangeAt(i);
        var rects = aRange.getClientRects();
        for (j=0; j<rects.length; j++) {
            result.push(rects[j]);
        }
    }
    return JSON.stringify(result);
}

Then from your Objective C code, you use do something like this:

NSString *rectsString = [webView stringByEvaluatingJavaScriptFromString:@"rectsForSelection();"];
NSData *rectsData = [rectsString dataUsingEncoding:NSUTF8StringEncoding];
NSArray *rects = [NSJSONSerialization JSONObjectWithData:rectsData
                                                 options:0
                                                   error:NULL]; //Do Your Own Error Checking

I'll add that this will get coordinates that are valid within your webView.scrollView, not your webView.

score 0 · Answer 3 · answered Oct 22 '13 at 15:59

have you tried that?

UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(getCoordinates:)];
//  [longPress setMinimumPressDuration:1];
[yourWebView addGestureRecognizer:longPress];


- (void)getCoordinates:(UILongPressGestureRecognizer *)sender {

CGPoint location = [sender locationInView:self.view];
NSLog(@"Tap at %1.0f, %1.0f", location.x, location.y);

}

score 0 · Answer 4 · edited May 23 '17 at 11:53

UIWebView actually renders the HTML into UIViews, specifically it will probably render the selectable text into UITextView, so what you have to do is try to tap into the right view's delegate methods.

Here's a hack that should work:

Wait until the web view is fully loaded.
Traverse over the UIWebView's subviews as described by Ole Begemann here.
Once you reach a UITextView tap into its delegate method, you could do something similar to a delegate chain to obtain this - here's a post about it
Implement the UITextViewDelegate method textViewDidChangeSelection: to get the selectedRange and interact with it.

** An alternative to step 3 and 4 is to use KVO to listen to changes in the textView's selectedRange.

How to get the coordinates for the selected text in UIWebView?

4 Answers4