Flutter开发02

今天来分享一下开发flutter遇到的一两个问题：

问题一：

flutter打开原生的WKWebView页面，想要禁止用户长按操作。

亲测无效的各种：

func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
        webView.evaluateJavaScript("document.documentElement.style.webkitTouchCallout='none';", completionHandler: nil)
        webView.evaluateJavaScript("document.documentElement.style.webkitUserSelect='none';", completionHandler: nil)
        
    }

if (@available(iOS 11.0, *)){
        for (UIView* subview in wkWebView.scrollView.subviews) {
            if ([subview isKindOfClass:NSClassFromString(@"WKContentView")])
            {
                for (UIGestureRecognizer* longPress in subview.gestureRecognizers) {
                    if ([longPress isKindOfClass:UILongPressGestureRecognizer.class]) {
                        [subview removeGestureRecognizer:longPress];
                        return;
                    }
                }
            }
        }
    }

      for (UIView* subview in wkWebView.scrollView.subviews) {
        if ([subview isKindOfClass:NSClassFromString(@"WKContentViewMinusAccessoryView")])
        {
            for (UIGestureRecognizer* longPress in subview.gestureRecognizers) {
                if ([longPress isKindOfClass:UILongPressGestureRecognizer.class]) {
                    [subview removeGestureRecognizer:longPress];
                }
            }
        }
    }

//禁止选择 css 配置相关
NSString*css = @"body{-webkit-user-select:none;-webkit-user-drag:none;}";

//css 选中样式取消
NSMutableString*javascript = [NSMutableStringstring];

[javascript appendString:@"var style = document.createElement('style');"];

[javascript appendString:@"style.type = 'text/css';"];

[javascript appendFormat:@"var cssContent = document.createTextNode('%@');", css];

[javascript appendString:@"style.appendChild(cssContent);"];

[javascript appendString:@"document.body.appendChild(style);"];

[javascript appendString:@"document.documentElement.style.webkitUserSelect='none';"];//禁止选择

[javascript appendString:@"document.documentElement.style.webkitTouchCallout='none';"];//禁止长按

//javascript 注入
WKUserScript *noneSelectScript = [[WKUserScript alloc] initWithSource:javascript

injectionTime:WKUserScriptInjectionTimeAtDocumentEnd

forMainFrameOnly:YES];

WKUserContentController*userContentController = [[WKUserContentControlleralloc] init];

[userContentController addUserScript:noneSelectScript];

WKWebViewConfiguration*configuration = [[WKWebViewConfigurationalloc] init];

configuration.userContentController = userContentController;

// 最后加载进入js
[self.wkWebView.configuration.userContentControlleraddUserScript:noneSelectScript];

下面是解决方法

• 简要描述：开发环境：Xcode：11.2 ，iOS：13.2。然后自己创建一个UILongPressGestureRecognizer替换掉系统的，即可。

第一步：

private var longP : UILongPressGestureRecognizer?

第二步：

let longP_ = UILongPressGestureRecognizer.init(target: self, action: #selector(longTapAction))
    longP = longP_
    longP!.delegate = self
    WKWeb.addGestureRecognizer(longP!)

第三步：实现代理方法

func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldBeRequiredToFailBy otherGestureRecognizer: UIGestureRecognizer) -> Bool {
        
        if gestureRecognizer == longP {
            return true
        } else {
            return false
        }
    }

• 说明：

/// 此方法指定只有gestureRecognizer被系统判定失败时，才会执行otherGestureRecognizer
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRequireFailureOfGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer NS_AVAILABLE_IOS(7_0);

/// 此方法指定只有otherGestureRecognizer被系统判定失败时，才会执行
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer NS_AVAILABLE_IOS(7_0);

问题二：

flutter在自动横竖屏切换的问题

问题描述：在开发flutter的时候，有的视频播放页面需要进行横屏切换，结果只显示了一半。

下面是解决方法

• 简要描述：开发环境同上，视频播放用的是WKWebView
  第一步：添加监听

UIDevice.current.beginGeneratingDeviceOrientationNotifications()
NotificationCenter.default.addObserver(self, selector: #selector(deviceOrientationDidChange), name: UIDevice.orientationDidChangeNotification, object: nil)

第二步：

@objc func deviceOrientationDidChange() {
    WKWeb.frame = UIScreen.main.bounds
}

问题三：

禁止截屏，录屏

// 禁止截屏
        weak var weakSelf = self
        NotificationCenter.default.addObserver(forName: UIApplication.userDidTakeScreenshotNotification, object: nil, queue: OperationQueue.main) { (_) in
            print("接到用户截屏的通知....")
            weakSelf?.notificationScreenshot()
        }
        // 禁止录屏
        if #available(iOS 11.0, *) {
            if UIScreen.main.isCaptured {
                NotificationCenter.default.addObserver(forName: UIScreen.capturedDidChangeNotification, object: nil, queue: OperationQueue.main) { (_) in
                    weakSelf?.notificationScreenshot()
                }
            }
        } else {
            // Fallback on earlier versions
        }

• 说明，一定要在AppDelegate中注册监听，否则回调有时候不好使。