如何攔截 MKMapView 或 UIWebView 對象上的觸摸事件？

Question

我不確定我做錯了什么，但我嘗試捕捉對MKMapView對象的觸摸。 我通過創建以下類對其進行了子類化：

#import <UIKit/UIKit.h>
#import <MapKit/MapKit.h>

@interface MapViewWithTouches : MKMapView {

}

- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *) event;   

@end

和實施：

#import "MapViewWithTouches.h"
@implementation MapViewWithTouches

- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *) event {

    NSLog(@"hello");
    //[super touchesBegan:touches   withEvent:event];

}
@end

但看起來當我使用這個類時，我在控制台上看不到任何東西：

MapViewWithTouches *mapView = [[MapViewWithTouches alloc] initWithFrame:self.view.frame];
[self.view insertSubview:mapView atIndex:0];

知道我做錯了什么嗎？

Answer 1

我發現實現這一目標的最佳方法是使用手勢識別器。 事實證明，其他方法涉及大量黑客式編程，這些編程不完美地復制了 Apple 的代碼，尤其是在多點觸控的情況下。

這就是我所做的：實現一個無法阻止且無法阻止其他手勢識別器的手勢識別器。 將其添加到地圖視圖中，然后根據您的喜好使用gestureRecognizer 的touchesBegan、touchesMoved 等。

如何檢測 MKMapView 中的任何點擊（無技巧）

WildcardGestureRecognizer * tapInterceptor = [[WildcardGestureRecognizer alloc] init];
tapInterceptor.touchesBeganCallback = ^(NSSet * touches, UIEvent * event) {
        self.lockedOnUserLocation = NO;
};
[mapView addGestureRecognizer:tapInterceptor];

通配符手勢識別器.h

//
//  WildcardGestureRecognizer.h
//  Copyright 2010 Floatopian LLC. All rights reserved.
//

#import <Foundation/Foundation.h>

typedef void (^TouchesEventBlock)(NSSet * touches, UIEvent * event);

@interface WildcardGestureRecognizer : UIGestureRecognizer {
    TouchesEventBlock touchesBeganCallback;
}
@property(copy) TouchesEventBlock touchesBeganCallback;


@end

通配符手勢識別器.m

//
//  WildcardGestureRecognizer.m
//  Created by Raymond Daly on 10/31/10.
//  Copyright 2010 Floatopian LLC. All rights reserved.
//

#import "WildcardGestureRecognizer.h"


@implementation WildcardGestureRecognizer
@synthesize touchesBeganCallback;

-(id) init{
    if (self = [super init])
    {
        self.cancelsTouchesInView = NO;
    }
    return self;
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    if (touchesBeganCallback)
        touchesBeganCallback(touches, event);
}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
}

- (void)reset
{
}

- (void)ignoreTouch:(UITouch *)touch forEvent:(UIEvent *)event
{
}

- (BOOL)canBePreventedByGestureRecognizer:(UIGestureRecognizer *)preventingGestureRecognizer
{
    return NO;
}

- (BOOL)canPreventGestureRecognizer:(UIGestureRecognizer *)preventedGestureRecognizer
{
    return NO;
}

@end

斯威夫特 3

let tapInterceptor = WildCardGestureRecognizer(target: nil, action: nil)
tapInterceptor.touchesBeganCallback = {
    _, _ in
    self.lockedOnUserLocation = false
}
mapView.addGestureRecognizer(tapInterceptor)

WildCardGestureRecognizer.swift

import UIKit.UIGestureRecognizerSubclass

class WildCardGestureRecognizer: UIGestureRecognizer {

    var touchesBeganCallback: ((Set<UITouch>, UIEvent) -> Void)?

    override init(target: Any?, action: Selector?) {
        super.init(target: target, action: action)
        self.cancelsTouchesInView = false
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
        super.touchesBegan(touches, with: event)
        touchesBeganCallback?(touches, event)
    }

    override func canPrevent(_ preventedGestureRecognizer: UIGestureRecognizer) -> Bool {
        return false
    }

    override func canBePrevented(by preventingGestureRecognizer: UIGestureRecognizer) -> Bool {
        return false
    }
}

Answer 2

經過一天的比薩餅，尖叫聲，我終於找到了解決方案！ 井井有條！

彼得，我在上面使用了你的技巧並對其進行了一些調整，最終得到了一個與 MKMapView 完美配合並且也應該與 UIWebView 配合使用的解決方案

MKTouchAppDelegate.h

#import <UIKit/UIKit.h>
@class UIViewTouch;
@class MKMapView;

@interface MKTouchAppDelegate : NSObject <UIApplicationDelegate> {
    UIWindow *window;
    UIViewTouch *viewTouch;
    MKMapView *mapView;
}
@property (nonatomic, retain) UIViewTouch *viewTouch;
@property (nonatomic, retain) MKMapView *mapView;
@property (nonatomic, retain) IBOutlet UIWindow *window;

@end

MKTouchAppDelegate.m

#import "MKTouchAppDelegate.h"
#import "UIViewTouch.h"
#import <MapKit/MapKit.h>

@implementation MKTouchAppDelegate

@synthesize window;
@synthesize viewTouch;
@synthesize mapView;


- (void)applicationDidFinishLaunching:(UIApplication *)application {

    //We create a view wich will catch Events as they occured and Log them in the Console
    viewTouch = [[UIViewTouch alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];

    //Next we create the MKMapView object, which will be added as a subview of viewTouch
    mapView = [[MKMapView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];
    [viewTouch addSubview:mapView];

    //And we display everything!
    [window addSubview:viewTouch];
    [window makeKeyAndVisible];


}


- (void)dealloc {
    [window release];
    [super dealloc];
}


@end

UIViewTouch.h

#import <UIKit/UIKit.h>
@class UIView;

@interface UIViewTouch : UIView {
    UIView *viewTouched;
}
@property (nonatomic, retain) UIView * viewTouched;

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event;

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event;

@end

UIViewTouch.m

#import "UIViewTouch.h"
#import <MapKit/MapKit.h>

@implementation UIViewTouch
@synthesize viewTouched;

//The basic idea here is to intercept the view which is sent back as the firstresponder in hitTest.
//We keep it preciously in the property viewTouched and we return our view as the firstresponder.
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
    NSLog(@"Hit Test");
    viewTouched = [super hitTest:point withEvent:event];
    return self;
}

//Then, when an event is fired, we log this one and then send it back to the viewTouched we kept, and voilà!!! :)
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    NSLog(@"Touch Began");
    [viewTouched touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    NSLog(@"Touch Moved");
    [viewTouched touchesMoved:touches withEvent:event];
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    NSLog(@"Touch Ended");
    [viewTouched touchesEnded:touches withEvent:event];
}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
    NSLog(@"Touch Cancelled");
}

@end

我希望這會幫助你們中的一些人！

干杯

Answer 3

UITapGestureRecognizer *tgr = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(handleGesture:)];   
tgr.numberOfTapsRequired = 2;
tgr.numberOfTouchesRequired = 1;
[mapView addGestureRecognizer:tgr];
[tgr release];


- (void)handleGesture:(UIGestureRecognizer *)gestureRecognizer
{
    if (gestureRecognizer.state != UIGestureRecognizerStateEnded)
        return;

    CGPoint touchPoint = [gestureRecognizer locationInView:mapView];
    CLLocationCoordinate2D touchMapCoordinate = [mapView convertPoint:touchPoint toCoordinateFromView:mapView];

    //.............
}

Answer 4

對於 MKMapView，真正有效的解決方案是使用手勢識別！

我想在拖動地圖或捏合縮放時停止更新我所在位置的地圖中心。

因此，創建您的手勢識別器並將其添加到 mapView ：

- (void)viewDidLoad {

    ...

    // Add gesture recognizer for map hoding
    UILongPressGestureRecognizer *longPressGesture = [[[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(handleLongPressAndPinchGesture:)] autorelease];
    longPressGesture.delegate = self;
    longPressGesture.minimumPressDuration = 0;  // In order to detect the map touching directly (Default was 0.5)
    [self.mapView addGestureRecognizer:longPressGesture];

    // Add gesture recognizer for map pinching
    UIPinchGestureRecognizer *pinchGesture = [[[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(handleLongPressAndPinchGesture:)] autorelease];
    pinchGesture.delegate = self;
    [self.mapView addGestureRecognizer:pinchGesture];

    // Add gesture recognizer for map dragging
    UIPanGestureRecognizer *panGesture = [[[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePanGesture:)] autorelease];
    panGesture.delegate = self;
    panGesture.maximumNumberOfTouches = 1;  // In order to discard dragging when pinching
    [self.mapView addGestureRecognizer:panGesture];
}

查看UIGestureRecognizer 類參考以查看所有可用的手勢識別器。

因為我們已經定義了 self 的委托，所以我們必須實現協議 UIGestureRecognizerDelegate ：

typedef enum {
    MapModeStateFree,                    // Map is free
    MapModeStateGeolocalised,            // Map centred on our location
    MapModeStateGeolocalisedWithHeading  // Map centred on our location and oriented with the compass
} MapModeState;

@interface MapViewController : UIViewController <CLLocationManagerDelegate, UIGestureRecognizerDelegate> {
    MapModeState mapMode;
}

@property (nonatomic, retain) IBOutlet MKMapView *mapView;
...

並覆蓋方法gestureRecognizer:gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer: 為了允許同時識別多個手勢，如果我理解正確：

// Allow to recognize multiple gestures simultaneously (Implementation of the protocole UIGestureRecognizerDelegate)
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
    return YES;
}

現在編寫將由我們的手勢識別器調用的方法：

// On map holding or pinching pause localise and heading
- (void)handleLongPressAndPinchGesture:(UIGestureRecognizer *)sender {
    // Stop to localise and/or heading
    if (sender.state == UIGestureRecognizerStateBegan && mapMode != MapModeStateFree) {
        [locationManager stopUpdatingLocation];
        if (mapMode == MapModeStateGeolocalisedWithHeading) [locationManager stopUpdatingHeading];
    }
    // Restart to localise and/or heading
    if (sender.state == UIGestureRecognizerStateEnded && mapMode != MapModeStateFree) {
        [locationManager startUpdatingLocation];
        if (mapMode == MapModeStateGeolocalisedWithHeading) [locationManager startUpdatingHeading];
    }
}

// On dragging gesture put map in free mode
- (void)handlePanGesture:(UIGestureRecognizer *)sender {
    if (sender.state == UIGestureRecognizerStateBegan && mapMode != MapModeStateFree) [self setMapInFreeModePushedBy:sender];
}

Answer 5

以防萬一有人像我一樣試圖做同樣的事情：我想在用戶點擊的地方創建一個注釋。 為此，我使用了UITapGestureRecognizer解決方案：

UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(didTapOnMap:)];
[self.mapView addGestureRecognizer:tapGestureRecognizer];
[tapGestureRecognizer setDelegate:self];

- (void)didTapOnMap:(UITapGestureRecognizer *)gestureRecognizer
{
    CGPoint point = [gestureRecognizer locationInView:self.mapView];
    CLLocationCoordinate2D coordinate = [self.mapView convertPoint:point toCoordinateFromView:self.mapView];
    .......
}

但是，當我點擊注釋時也會調用didTapOnMap:並且會創建一個新注釋。 解決方案是實現UIGestureRecognizerDelegate ：

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
{
    if ([touch.view isKindOfClass:[MKAnnotationView class]])
    {
        return NO;
    }
    return YES;
}

Answer 6

您可能需要覆蓋一個透明視圖來捕捉觸摸，就像使用基於 UIWebView 的控件經常做的那樣。 Map View 已經通過觸摸做了一些特殊的事情，以便允許移動、居中、縮放地圖等......消息不會冒泡到您的應用程序中。

我能想到的另外兩個（未經測試）選項：

1）通過IB退出第一響應者並將其設置為“文件的所有者”以允許文件的所有者響應觸摸。 我懷疑這會起作用，因為 MKMapView 擴展了 NSObject，而不是 UIView，因此觸摸事件仍然可能不會傳播給您。

2) 如果您想在 Map 狀態更改時（例如縮放時）進行捕獲，只需實現 MKMapViewDelegate 協議來偵聽特定事件。 我的預感是，這是您輕松捕獲某些交互的最佳方法（沒有在地圖上實現透明視圖）。 不要忘記將包含 MKMapView 的視圖控制器設置為地圖的委托（ map.delegate = self ）。

祝你好運。

Answer 7

我還沒有嘗試過，但很有可能 MapKit 是基於類集群的，因此對其進行子類化既困難又無效。

我建議將 MapKit 視圖設為自定義視圖的子視圖，這樣您就可以在觸摸事件到達之前攔截它們。

Answer 8

所以在搞了半天之后，我發現了以下內容：

1. 正如其他人發現的那樣，捏合是行不通的。 我嘗試了子類化 MKMapView 和上面描述的方法（攔截它）。 結果是一樣的。

2. 在斯坦福 iPhone 的視頻中，蘋果的一個人說，如果你“傳輸”觸摸請求（也就是上面描述的兩種方法），很多 UIKit 的東西會導致很多錯誤，你可能不會讓它工作。

3. 解決方案：在此處描述： Intercepting/Hijacking iPhone Touch Events for MKMapView 。 基本上你在任何響應者得到它之前“捕捉”事件，並在那里解釋它。

Answer 9

在 Swift 3.0 中

import UIKit
import MapKit

class CoordinatesPickerViewController: UIViewController {

    @IBOutlet var mapView: MKMapView!
    override func viewDidLoad() {
        super.viewDidLoad()

        let tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(clickOnMap))
        mapView.addGestureRecognizer(tapGestureRecognizer)
    }

    @objc func clickOnMap(_ sender: UITapGestureRecognizer) {

        if sender.state != UIGestureRecognizerState.ended { return }
        let touchLocation = sender.location(in: mapView)
        let locationCoordinate = mapView.convert(touchLocation, toCoordinateFrom: mapView)
        print("Tapped at lat: \(locationCoordinate.latitude) long: \(locationCoordinate.longitude)")

    }

}

Answer 10

使 MKMapView 成為自定義視圖的子視圖並實現

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event

在自定義視圖中返回 self 而不是子視圖。

Answer 11

謝謝你的披薩和尖叫——你為我節省了很多時間。

multipletouchenabled 將偶爾工作。

viewTouch.multipleTouchEnabled = TRUE;

最后，當我需要捕捉觸摸時，我切換了視圖（與需要縮放不同的時間點）：

    [mapView removeFromSuperview];
    [viewTouch addSubview:mapView];
    [self.view insertSubview:viewTouch atIndex:0];

Answer 12

我注意到您可以跟蹤觸摸的數量和位置，並在視圖中獲取每個位置：

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    NSLog(@"Touch Moved %d", [[event allTouches] count]);

 NSEnumerator *enumerator = [touches objectEnumerator];
 id value;

 while ((value = [enumerator nextObject])) {
  NSLog(@"touch description %f", [value locationInView:mapView].x);
 }
    [viewTouched touchesMoved:touches withEvent:event];
}

有沒有其他人嘗試使用這些值來更新地圖的縮放級別？ 這將是記錄開始位置，然后是結束位置，計算相對差異並更新地圖的問題。

我正在使用 Martin 提供的基本代碼，這看起來會起作用......

Answer 13

這是我放在一起的內容，它確實允許在模擬器中進行縮放（尚未在真正的 iPhone 上嘗試過），但我認為會很好：

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    NSLog(@"Touch Began %d", [touches count]);
 reportTrackingPoints = NO;
 startTrackingPoints = YES;
    [viewTouched touchesBegan:touches withEvent:event];
}

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
 if ([[event allTouches] count] == 2) {
  reportTrackingPoints = YES;
  if (startTrackingPoints == YES) {
   BOOL setA = NO;
   NSEnumerator *enumerator = [[event allTouches] objectEnumerator];
   id value;
   while ((value = [enumerator nextObject])) {
    if (! setA) {
     startPointA = [value locationInView:mapView];
     setA = YES;
    } else {
     startPointB = [value locationInView:mapView];
    }
   }
   startTrackingPoints = NO;
  } else {
   BOOL setA = NO;
   NSEnumerator *enumerator = [[event allTouches] objectEnumerator];
   id value;
   while ((value = [enumerator nextObject])) {
    if (! setA) {
     endPointA = [value locationInView:mapView];
     setA = YES;
    } else {
     endPointB = [value locationInView:mapView];
    }
   }
  }
 }
 //NSLog(@"Touch Moved %d", [[event allTouches] count]);
    [viewTouched touchesMoved:touches withEvent:event];
}

- (void) updateMapFromTrackingPoints {
 float startLenA = (startPointA.x - startPointB.x);
 float startLenB = (startPointA.y - startPointB.y);
 float len1 = sqrt((startLenA * startLenA) + (startLenB * startLenB));
 float endLenA = (endPointA.x - endPointB.x);
 float endLenB = (endPointA.y - endPointB.y);
 float len2 = sqrt((endLenA * endLenA) + (endLenB * endLenB));
 MKCoordinateRegion region = mapView.region;
 region.span.latitudeDelta = region.span.latitudeDelta * len1/len2;
 region.span.longitudeDelta = region.span.longitudeDelta * len1/len2;
 [mapView setRegion:region animated:YES];
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
 if (reportTrackingPoints) {
  [self updateMapFromTrackingPoints];
  reportTrackingPoints = NO;
 }


    [viewTouched touchesEnded:touches withEvent:event];
}

主要思想是，如果用戶使用兩根手指，您可以跟蹤這些值。 我在startPoints A和B中記錄起點和終點。然后我記錄當前的跟蹤點，當我完成后，在touchesEnded上，我可以調用一個例程來計算我開始的點之間的線的相對長度，以及我使用簡單斜邊計算結束的點之間的線。 它們之間的比率是縮放量：我將區域跨度乘以該量。

希望它對某人有用。

Answer 14

我從 MystikSpiral 的回答中提出了“疊加”透明視圖的想法，它非常適合我想要實現的目標； 快速，干凈的解決方案。

簡而言之，我有一個自定義 UITableViewCell（在 IB 中設計），左側有一個 MKMapView，右側有一些 UILabels。 我想制作自定義單元格，以便您可以在任何地方觸摸它，這將推動一個新的視圖控制器。 然而，觸摸地圖並沒有將觸摸“向上”傳遞給 UITableViewCell，直到我只是在它的頂部（在 IB 中）添加了一個與地圖視圖相同大小的 UIView 並使其背景成為代碼中的“清晰顏色”（不認為您可以在 IB 中設置 clearColor 嗎？？）：

dummyView.backgroundColor = [UIColor clearColor];

認為它可能會幫助別人； 當然，如果您想為表格視圖單元格實現相同的行為。

Answer 15

我不明白為什么其他答案如此復雜。 解決方案實際上只是一行：

mapView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(mapTapped)))

@objc func mapTapped() {}