godot/platform/iphone/godot_view_gesture_recognizer.m
Sergey Minakov e6d7e01a72 iOS: added delay gesture recognizer
This gesture recognizer will prevent GodotView from processing unwanted gestures.
Emulates UIScrollView behavior.
Fires delayed touches on significant movement.
2020-07-26 16:05:58 +03:00

172 lines
5.7 KiB
Objective-C

/*************************************************************************/
/* godot_view_gesture_recognizer.m */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md). */
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/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
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/*************************************************************************/
#import "godot_view_gesture_recognizer.h"
// Using same delay interval that is used for `UIScrollView`
const NSTimeInterval kGLGestureDelayInterval = 0.150;
// Minimum distance for touches to move to fire
// a delay timer before scheduled time.
// Should be the low enough to not cause issues with dragging
// but big enough to allow click to work.
const CGFloat kGLGestureMovementDistance = 0.5;
@interface GodotViewGestureRecognizer ()
// Timer used to delay begin touch message.
// Should work as simple emulation of UIDelayedAction
@property(strong, nonatomic) NSTimer *delayTimer;
// Delayed touch parameters
@property(strong, nonatomic) NSSet *delayedTouches;
@property(strong, nonatomic) UIEvent *delayedEvent;
@end
@implementation GodotViewGestureRecognizer
- (instancetype)init {
self = [super init];
self.cancelsTouchesInView = YES;
self.delaysTouchesBegan = YES;
self.delaysTouchesEnded = YES;
return self;
}
- (void)dealloc {
if (self.delayTimer) {
[self.delayTimer invalidate];
self.delayTimer = nil;
}
if (self.delayedTouches) {
self.delayedTouches = nil;
}
if (self.delayedEvent) {
self.delayedEvent = nil;
}
[super dealloc];
}
- (void)delayTouches:(NSSet *)touches andEvent:(UIEvent *)event {
[self.delayTimer fire];
self.delayedTouches = touches;
self.delayedEvent = event;
self.delayTimer = [NSTimer
scheduledTimerWithTimeInterval:kGLGestureDelayInterval
target:self
selector:@selector(fireDelayedTouches:)
userInfo:nil
repeats:NO];
}
- (void)fireDelayedTouches:(id)timer {
[self.delayTimer invalidate];
self.delayTimer = nil;
if (self.delayedTouches) {
[self.view touchesBegan:self.delayedTouches withEvent:self.delayedEvent];
}
self.delayedTouches = nil;
self.delayedEvent = nil;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
NSSet *cleared = [self copyClearedTouches:touches phase:UITouchPhaseBegan];
[self delayTouches:cleared andEvent:event];
[cleared release];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
NSSet *cleared = [self copyClearedTouches:touches phase:UITouchPhaseMoved];
if (self.delayTimer) {
// We should check if movement was significant enough to fire an event
// for dragging to work correctly.
for (UITouch *touch in cleared) {
CGPoint from = [touch locationInView:self.view];
CGPoint to = [touch previousLocationInView:self.view];
CGFloat xDistance = from.x - to.x;
CGFloat yDistance = from.y - to.y;
CGFloat distance = sqrt(xDistance * xDistance + yDistance * yDistance);
// Early exit, since one of touches has moved enough to fire a drag event.
if (distance > kGLGestureMovementDistance) {
[self.delayTimer fire];
[self.view touchesMoved:cleared withEvent:event];
[cleared release];
return;
}
}
[cleared release];
return;
}
[self.view touchesMoved:cleared withEvent:event];
[cleared release];
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[self.delayTimer fire];
NSSet *cleared = [self copyClearedTouches:touches phase:UITouchPhaseEnded];
[self.view touchesEnded:cleared withEvent:event];
[cleared release];
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
[self.delayTimer fire];
[self.view touchesCancelled:touches withEvent:event];
};
- (NSSet *)copyClearedTouches:(NSSet *)touches phase:(UITouchPhase)phaseToSave {
NSMutableSet *cleared = [touches mutableCopy];
for (UITouch *touch in touches) {
if (touch.phase != phaseToSave) {
[cleared removeObject:touch];
}
}
return cleared;
}
@end