how to detect when UIWebView starts selecting text?

问题

I have a UIWebView which shows static content and reacts to various swipe gestures through its controller.

The text selection has been disabled but now I am working on a new feature to allow text selection and present a custom context menu.

Now I need to be able to detect when the text selection is active so that I can turn off the swipe gestures.

The only method I can think of is to check if there is selected text using JS in the swipe handler methods. Any other ideas? Does anybody know how to do this better?

Thanks.

回答1:

when the user select a text the menuViewController will shown up .. you can detect that by add a notification on your viewController

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(menuShown) name:UIMenuControllerDidShowMenuNotification object:nil];

same case to detect for the menu hide.

回答2:

You may be able to use a "Long Press Gesture Recognizer" to bind to the UIWebView. You can calibrate it to the timing required for a user to press and hold on a text before the text is selected.

回答3:

I ended up using the following method to disable and enable the gesture recognizers using the Rangy library. Works great.

- (BOOL) isSelectionActive
{
    NSString * resultStr = [self.contentView stringByEvaluatingJavaScriptFromString:
                            @"rangy.getSelection().isCollapsed"];

    NSLog(@"resultStr: %@", resultStr );

    if ([resultStr isEqualToString:@"true"]) {
        return NO;
    }
    else {
        return YES;
    }
}

来源：https://stackoverflow.com/questions/9621966/how-to-detect-when-uiwebview-starts-selecting-text

标签

javascript

ios

uiwebview