René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Gestures: tap and double tap on the same View","articleBody":"**Environment**\r\n - CLI: latest\r\n - Cross-platform modules:  5.4.0\r\n - Android Runtime:  5.4.0\r\n - iOS Runtime: 5.4.0\r\n\r\n**Describe the bug**\r\nWhen you have a tap and double tap gesture recognizer on a view and you attempt to double tap, the tap handler fires. The tap gesture event should not fire if you're attempting a double tap. Take a look at the \"Additional context\" for the commit that allowed this.\r\n\r\n**To Reproduce**\r\n\r\n```\r\nexport class TestLayout extends StackLayout {\r\n    onLoaded() {\r\n        super.onLoaded();\r\n\r\n        this.on(GestureTypes.tap, () =\u003e console.log('Tapped'));\r\n        this.on(GestureTypes.doubleTap, () =\u003e console.log('Double tapped'));\r\n    }\r\n}\r\n```\r\n\r\nIf you attempt to double tap on the `TestLayout`, the console will show:\r\n\u003e `Tapped`\r\n\u003e `Double tapped`\r\n\r\n**Expected behavior**\r\nIf you try to double tap on a view with a tap gesture recognizer and a double tap gesture recognizer, the double tap event should fire and the tap should not. \r\n\r\n**Additional context**\r\n\r\nI have been working through this issue with @MartoYankov .\r\n\r\n[Here is the commit that allowed simultaneous gesture events](https://github.com/NativeScript/NativeScript/commit/fe72a43e49cc318d7a4cc2488d66aaf9e07feab1)\r\n\r\n[Here are the docs to the delegate method that could be implemented for iOS](https://developer.apple.com/documentation/uikit/uigesturerecognizerdelegate/1624229-gesturerecognizer?language=objc)\r\n- I have already implemented this ^ for iOS (see below). The issue now is getting the same functionality for Android.\r\n\r\n\r\n**Potential solution (iOS)**\r\n\r\n`gestures.ios.ts`\r\n```\r\nclass UIGestureRecognizerDelegateImpl extends NSObject implements UIGestureRecognizerDelegate {\r\n    public static ObjCProtocols = [UIGestureRecognizerDelegate];\r\n\r\n    public gestureRecognizerShouldRecognizeSimultaneouslyWithGestureRecognizer(gestureRecognizer: UIGestureRecognizer, otherGestureRecognizer: UIGestureRecognizer): boolean {\r\n        // If both gesture recognizers are of type UITapGestureRecognizer, do not allow\r\n        // simultaneous recognition.\r\n        if (gestureRecognizer instanceof UITapGestureRecognizer \u0026\u0026 otherGestureRecognizer instanceof UITapGestureRecognizer) {\r\n            return false;\r\n        }\r\n        return true;\r\n    }\r\n\r\n    public gestureRecognizerShouldRequireFailureOfGestureRecognizer(gestureRecognizer: UIGestureRecognizer, otherGestureRecognizer: UIGestureRecognizer): boolean {\r\n        // If both gesture recognizers are of type UITapGestureRecognizer \u0026 one of them is a doubleTap,\r\n        // we must require a failure.\r\n        if (gestureRecognizer instanceof UITapGestureRecognizer\r\n            \u0026\u0026 otherGestureRecognizer instanceof UITapGestureRecognizer\r\n            \u0026\u0026 otherGestureRecognizer.numberOfTapsRequired === 2) {\r\n            return true;\r\n        }\r\n        return false;\r\n    }\r\n}\r\n```","author":{"url":"https://github.com/MCurran16","@type":"Person","name":"MCurran16"},"datePublished":"2019-05-23T18:45:26.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/7281/NativeScript/issues/7281"}