我试图通过使用类别并覆盖 canPerformAction 并为复制、剪切和粘贴选择器返回 NO 来禁用 UIWebView 中的复制/粘贴。
当我加载网页或所有其他文档格式（例如 docx、pptx、rtf、txt）时，它按预期工作，但当我将 PDF 文档加载到 UIWebView 时却没有。
似乎有一些不同的机制可以处理 UIWebView 中的 PDF 文档，它处理/响应复制选择器，因此我无法阻止它。
我还尝试禁用 UIWebView 的 UIScrollView 的所有子视图的用户交互，这对于除 PDF 之外的其他文档格式都适用。
任何人都可以帮助弄清楚如何在 UIWebView 中为 PDF 文档禁用复制吗？
好的，所以我自己也遇到过同样的问题，并且似乎找到了解决方案，即使它是部分的。
我所做的是使用 UILongPressGestureRecognizer 禁用可能导致复制/粘贴的长按手势。
编码：
UILongPressGestureRecognizer* longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(handleLongPress:)]; // allocating the UILongPressGestureRecognizer
longPress.allowableMovement=100; // Making sure the allowable movement isn't too narrow
longPress.minimumPressDuration=0.3; // This is important - the duration must be long enough to allow taps but not longer than the period in which the scroll view opens the magnifying glass
longPress.delegate=self; // initialization stuff
longPress.delaysTouchesBegan=YES;
longPress.delaysTouchesEnded=YES;
longPress.cancelsTouchesInView=YES; // That's when we tell the gesture recognizer to block the gestures we want
[webView addGestureRecognizer:longPress]; // Add the gesture recognizer to the view and scroll view then release
[[webView scrollView] addGestureRecognizer:longPress];
[longPress release];
这个解决方案对我有用：
方法 1 - 检测自定义长按
A) 创建一个 UILongPressGestureRecogniser 的子类。
B）canBePreventedByGestureRecognizer:在您的子类中包含该方法，如下所示：
标题：
#import <UIKit/UIKit.h>
@interface CustomLongPress : UILongPressGestureRecognizer
@end
执行：
#import "CustomLongPress.h"
@implementation CustomLongPress
- (BOOL)canBePreventedByGestureRecognizer:(UIGestureRecognizer*)preventedGestureRecognizer {
return NO;
}
@end
这是子类中唯一需要的代码。
C) 打开包含您的 uiwebview/pdf 阅读器的视图。包括您的子类：#import "CustomLongPress.h"然后将自定义 UILongPressGestureRecogniser 添加到您的 UIWebView，如下所示：
- (void)viewDidLoad
{
[super viewDidLoad];
//Load UIWebView etc
//Add your custom gesture recogniser
CustomLongPress * longPress = [[CustomLongPress alloc] initWithTarget:self action:@selector(longPressDetected)];
[pdfWebView addGestureRecognizer:longPress];
}
D）检测长按并关闭您的 UIWebView 的 userInteraction 然后再打开：
-(void)longPressDetected {
NSLog(@"long press detected");
[pdfWebView setUserInteractionEnabled:NO];
[pdfWebView setUserInteractionEnabled:YES];
}
显然，这是因为 UIWebView 使用自己的手势识别器捕获长按，排除您添加的任何其他手势识别器。但是将手势识别器子类化并通过向方法返回“NO”来防止它们被排除canBePreventedByGestureRecognizer:会覆盖默认行为。
一旦您可以检测到对 PDF 的长按，将 userInteraction 关闭然后再打开会阻止 UIWebView 执行其默认行为，即启动“复制/定义”UIMenu，或者，如果长按链接，则启动弹出操作表使用“复制”和“打开”操作。
方法 2 - 捕获 UIMenu NSNotification
或者，如果您只想阻止“复制/定义”UIMenu（但不影响长按），您可以将此行（监听 UIMenuControllerDidShowMenuNotification）添加到您的 ViewDidLoad：
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(menuShown) name:UIMenuControllerDidShowMenuNotification object:nil];
然后添加此方法，使用与上述相同的 userInteraction Off/On 方法：
-(void)menuShown {
NSLog(@"menu shown");
[pdfWebView setUserInteractionEnabled:NO];
[pdfWebView setUserInteractionEnabled:YES];
}
第一种方法取自：https ://devforums.apple.com/thread/72521?start=25&tstart=0 ，第二种方法取自 Stack 上的某个地方，抱歉忘记在哪里了。如果您知道，请包括在内。
很好的答案祖巴巴。我正在使用 webView 显示彩色和粗体文本，我遇到了同样的问题。我将您的解决方案放入一个方法中，并在初始化 webView 后立即调用它。我似乎不需要代表。
self.textView = [[UIWebView alloc] initWithFrame:textFrame];
[self longPress:self.textView];
- (void)longPress:(UIView *)webView {
UILongPressGestureRecognizer* longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(handleLongPress)]; // allocating the UILongPressGestureRecognizer
longPress.allowableMovement=100; // Making sure the allowable movement isn't too narrow
longPress.minimumPressDuration=0.3; // This is important - the duration must be long enough to allow taps but not longer than the period in which the scroll view opens the magnifying glass
longPress.delaysTouchesBegan=YES;
longPress.delaysTouchesEnded=YES;
longPress.cancelsTouchesInView=YES; // That's when we tell the gesture recognizer to block the gestures we want
[webView addGestureRecognizer:longPress]; // Add the gesture recognizer to the view and scroll view then release
[webView addGestureRecognizer:longPress];
}
- (void)handleLongPress {
}
如果有人需要 Zubaba 在 Swift 3 中的回答；
let longPress = UILongPressGestureRecognizer(target: self, action: #selector(handleLongPress))
longPress.allowableMovement = 100
longPress.minimumPressDuration = 0.3
longPress.delegate = self
longPress.delaysTouchesBegan = true
longPress.delaysTouchesEnded = true
longPress.cancelsTouchesInView = true
yourWebView.addGestureRecognizer(longPress)
yourWebView.scrollView.addGestureRecognizer(longPress)
func handleLongPress() {
// Show some alert to inform user or do nothing.
}
这是对 Zubaba 在 Swift 3 中的回答的修改，最终帮助我消除了警告。我将作业更改longPress.delegate = self为 longPress.delegate = self as? UIGestureRecognizerDelegate.
let longPress = UILongPressGestureRecognizer(target: self, action: #selector(handleLongPress))
longPress.allowableMovement = 100
longPress.minimumPressDuration = 0.3
longPress.delegate = self as? UIGestureRecognizerDelegate
longPress.delaysTouchesBegan = true
longPress.delaysTouchesEnded = true
longPress.cancelsTouchesInView = true
webView.addGestureRecognizer(longPress)
webView.scrollView.addGestureRecognizer(longPress)
webView.loadRequest(request)
1.ios11 iphone6 Object-C无复制/粘贴/lookUp/share
2.
viewDidLoad{
.......
[self setupExclude];
}
- (void)setupExclude{
UILongPressGestureRecognizer *longPress = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(longPG)];
longPress.minimumPressDuration = 0.2;
[self.webview addGestureRecognizer:longPress];
UITapGestureRecognizer *singleTapGesture = [[UITapGestureRecognizer alloc]initWithTarget:self action:nil];
singleTapGesture.numberOfTapsRequired = 1;
singleTapGesture.numberOfTouchesRequired = 1;
[self.webview addGestureRecognizer:singleTapGesture];
UITapGestureRecognizer *doubleTapGesture = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(longPG)];
doubleTapGesture.numberOfTapsRequired = 2;
doubleTapGesture.numberOfTouchesRequired = 1;
[self.webview addGestureRecognizer:doubleTapGesture];
[singleTapGesture requireGestureRecognizerToFail:doubleTapGesture];
}
- (BOOL)canPerformAction:(SEL)action withSender:(id)sender{
BOOL res = [super canPerformAction:action withSender:sender];
UIMenuController.sharedMenuController.menuVisible = NO;
self.webview.userInteractionEnabled = NO;
self.webview.userInteractionEnabled = YES;
return res;
}
- (void)longPG{
UIMenuController.sharedMenuController.menuVisible = NO;
self.webview.userInteractionEnabled = NO;
self.webview.userInteractionEnabled = YES;
}
3. 完成！
寻找 Xamarin.iOS 解决方案。
var longPressGestureRecognizer = new CustomLongPressGestureRecognizer ((UILongPressGestureRecognizer obj) =>
{
Console.WriteLine ("CustomLongPressGestureRecognizer action");
});
webView.AddGestureRecognizer (longPressGestureRecognizer);
Zubaba 给出的方法可能如下所示：
public class ZubabaLongPressGestureRecognizer : UIKit.UILongPressGestureRecognizer
{
public ZubabaLongPressGestureRecognizer (Action<UILongPressGestureRecognizer> action)
: base (action)
{
AllowableMovement = 100;
MinimumPressDuration = 0.3;
DelaysTouchesBegan = true;
DelaysTouchesEnded = true;
CancelsTouchesInView = true;
}
}
打开/复制/取消菜单仍然显示第一次长时间保存每个 PDF 页面的链接。但是，在第一次长按之后，它不会正确显示在该页面上。这取决于 PDF 页面并不能让我相信有可用的解决方案。
Johnny Rockex 的解决方案可能如下所示：
public class RockexLongPressGestureRecognizer : UIKit.UILongPressGestureRecognizer
{
public RockexLongPressGestureRecognizer(UIKit.UIWebView webView, Action<UILongPressGestureRecognizer> action) :
base(UserInteractionAction(webView) + action)
{
}
private static Action<UILongPressGestureRecognizer> UserInteractionAction(UIKit.UIWebView webView)
{
return (UILongPressGestureRecognizer obj) =>
{
webView.UserInteractionEnabled = false;
webView.UserInteractionEnabled = true;
};
}
public override bool CanPreventGestureRecognizer(UIGestureRecognizer preventedGestureRecognizer)
{
return false;
}
}
和
notificationToken1 = UIMenuController.Notifications.ObserveMenuFrameDidChange (Callback);
notificationToken2 = NSNotificationCenter.DefaultCenter.AddObserver(UIMenuController.DidShowMenuNotification, Callback);
我什么也做不了。帮助其他人在 Xamarin.iOS 修复方面做得更好
UILongPressGestureRecognizer 位于 UIPDFPageView 中。要访问此视图，请查看 Debug 菜单中的视图层次结构，目前您可以在将 pdf 加载到 Web 视图后访问此视图：
let pdfPageView = myWebView.scrollview?.subviews[0]?.subviews[0]
然后在传递 pdfPageView 时删除长按使用此方法：
func removeLongPressFromView(view: UIView){
if let gestures = view.gestureRecognizers{
for gesture in gestures{
if gesture is UILongPressGestureRecognzier{
view.removeGestureRecognizer(gesture)
}
}
}
}