Come posso utilizzare lo zoom pizzico (UIPinchGestureRecognizer) per modificare la larghezza di un UITextView?

Question

Posso ottenere il gestore UIPinchGestureRecognizer per lavorare con il ridimensionamento di un oggetto ma non voglio ridimensionarlo. Voglio cambiare la dimensione. Ad esempio, ho uno UITextView e ho allegato un gesto UIPinchGestureRecognizer e se l'utente si pizzica, voglio cambiare la larghezza della vista testo in modo che corrisponda al pizzico. Non voglio ridimensionarlo in modo che lo UITextView sia più grande (zoom).

Answer 1

Penso che ciò che si vuole fare è semplicemente moltiplicando la larghezza del telaio della vostra textView con la scala del sistema di riconoscimento gesto:

CGFloat scale = gestureRecognizer.scale; 
CGRect newFrame = textView.frame; 
newFrame.size = CGSizeMake(scale*newFrame.size.width, newFrame.size.height); 
textView.frame = newFrame; 

O non è questo che vuoi dire?

Answer 2

Sto facendo la stessa cosa. aggiornerò questo post se ho trovato come farlo.

Prova questo, il lavoro per me (per UIView):

- (IBAction)handlePinchGesture:(UIGestureRecognizer *)sender { 
    static CGRect initialBounds; 

    UIView *_view = sender.view; 

    if (sender.state == UIGestureRecognizerStateBegan) 
    { 
     initialBounds = _view.bounds; 
    } 
    CGFloat factor = [(UIPinchGestureRecognizer *)sender scale]; 

    CGAffineTransform zt = CGAffineTransformScale(CGAffineTransformIdentity, factor, factor); 
    _view.bounds = CGRectApplyAffineTransform(initialBounds, zt); 
    return; 
} 

Answer 3

Ho quattro routine che si occupano di pizzicare di un campo di testo. Il riconoscitore di gesti è la routine principale. Vede se i campi di testo selezionati verranno rimossi dallo schermo, non lo voglio. Se non lo sono, allora gli dico di pizzicarsi con la scala del gesto. Se ci sono più selezioni, invio una notifica per coloro che non rimuoveranno lo schermo per pizzicarsi.

//-------------------------------------------------------------------------------------------------------- 
    // pinchElement 
    // Description: Called to di the element scale, in our case, we are adjusting the length. 
    // 
    //-------------------------------------------------------------------------------------------------------- 

- (void)pinchElement:(CGFloat)scale { 

     //Grab how big we are now 
    CGRect textFieldBounds = textField.bounds; 

     //Multiple the Scale of the Pinch by the Width to get our new width. 
    CGFloat newWidth = textFieldBounds.size.width * scale; 

    CGFloat widthChange = newWidth - textFieldBounds.size.width; 
    CGRect newBounds = CGRectMake(0, 0, newWidth, textFieldBounds.size.height); 

    [textField setBounds: newBounds]; 
    [textField setCenter: CGPointMake(textField.center.x + widthChange/2, textField.center.y)] ; 
    [self contentSizeChanged]; 

} 
    //-------------------------------------------------------------------------------------------------------- 
    // pinchOffScreen 
    // Description: Called to see if the Pinch Gesture will cause element to go off screen Gesture 
    // 
    //-------------------------------------------------------------------------------------------------------- 

- (BOOL)pinchOffScreen:(CGFloat)scale { 

     //Grab how big we are now 
    CGRect textFieldBounds = textField.bounds; 

     //Multiple the Scale of the Pinch by the Width to get our new width. 
    CGFloat newWidth = textFieldBounds.size.width * scale; 


     //Figure out our Change in Width so we can calculate our new Zen Center 
    CGRect newElementBounds = CGRectMake(0, 0, newWidth+ kElementFrameOffset*2 + kElementContentFrameOffset*2, textFieldBounds.size.height + kElementFrameOffset*2 + kElementContentFrameOffset*2); 


     //We want to be sure that we dont size beyond our bounds, find our Parent Origin. 

    CGRect elementBoundsInSuperView = [self convertRect:newElementBounds toView:[self superview]]; 

    CGFloat xPosition = CGRectGetMidX(elementBoundsInSuperView); 
    CGFloat yPosition = CGRectGetMidY(elementBoundsInSuperView); 


    BOOL offScreen = [self calcOffEditorFromXposition:xPosition yPosition:yPosition fromBoundsInSuperView:elementBoundsInSuperView]; 
    return offScreen; 

} 

    //-------------------------------------------------------------------------------------------------------- 
    // handlePinchGesture 
    // Description: Called when we get a Pinch Gesture 
    //     We want to override the default scaling and set the width.    
    // 
    //-------------------------------------------------------------------------------------------------------- 

- (void)handlePinchGesture:(UIPinchGestureRecognizer *)gestureRecognizer { 
    if (IoUIDebug & IoUIDebugSelectorNames) { 
     NSLog(@"%@ - %@", INTERFACENAME, NSStringFromSelector(_cmd)); 
    } 

     // UIView *element = [gestureRecognizer view]; 

    if ([gestureRecognizer state] == UIGestureRecognizerStateBegan) { 

      //We are resizing, Select ourself 



      [self selectSelf]; 
    } 

    if ([gestureRecognizer state] == UIGestureRecognizerStateBegan || [gestureRecognizer state] == UIGestureRecognizerStateChanged) { 

     NSSet *selectedElements = [[(IoScreenEditorViewController *)UIAppDelegate.ioMainViewController.currentViewController editorContentViewController] selectedElements]; 

     BOOL aSelectedElementOffscreen = FALSE; 
     for (IoUIScreenElement* element in selectedElements) { 
      if ([element pinchOffScreen:[gestureRecognizer scale]]) { 
       aSelectedElementOffscreen = TRUE; 
       break; 
      } 
     } 
     if (!aSelectedElementOffscreen) { 

      [self pinchElement:[gestureRecognizer scale]]; 

       // Let others know they are moving if they are selected 
       // Setup our data for the Notification 
      NSMutableDictionary *theUserInfo = [[[NSMutableDictionary alloc] initWithCapacity:1] autorelease]; 
      [theUserInfo setObject:self forKey:@"ElementWithGesture"]; 


      NSNumber * scaleAsNumber = [[NSNumber alloc] initWithFloat:[gestureRecognizer scale]]; 
      [theUserInfo setValue:scaleAsNumber forKey:@"GestureScale"]; 
      [theUserInfo setObject:gestureRecognizer forKey:@"TheGestureRecognizer"]; 
      [scaleAsNumber release]; 
       // Post the Group Rotation Notification. 
      [[NSNotificationCenter defaultCenter] postNotificationName:kNCSEGroupPinchGesture 
                   object:nil 
                   userInfo:theUserInfo];  
     } 
     [gestureRecognizer setScale:1]; 
    } 
    if ([gestureRecognizer state] == UIGestureRecognizerStateEnded) { 


    } 


} 



    //-------------------------------------------------------------------------------------------------------- 
    //  groupHandlePinchGesture: 
    // Description: For a groupPinch Notification. Move it! within bounds of course 
    // 
    //-------------------------------------------------------------------------------------------------------- 

- (void) groupHandlePinchGesture:(NSNotification*)notification{ 

    if (IoUIDebug & IoUIDebugSelectorNames) { 
     NSLog(@"%@ - %@", INTERFACENAME, NSStringFromSelector(_cmd)); 
    } 

    IoUIScreenElement *element = (IoUIScreenElement *) [[notification userInfo] objectForKey:@"ElementWithGesture"]; 
     //UIRotationGestureRecognizer *gestureRecognizer = (UIRotationGestureRecognizer *) [[notification userInfo] objectForKey:@"TheGestureRecognizer"]; 

    NSNumber *scaleAsNumber = [[notification userInfo] valueForKey:@"GestureScale"]; 
    CGFloat scale = [scaleAsNumber floatValue]; 


    if (IOFNOTEQUAL(self, element) & [self isSelected]){ 
     [self pinchElement: scale]; 
    } 

} 

Answer 4

Devi usare in rapida:

func pinchgsterAction(gesture:UIPinchGestureRecognizer){ 
    if (gesture.state == UIGestureRecognizerState.Changed) { 
     let scale:CGFloat = gesture.scale 
     gesture.view.transform = CGAffineTransformScale(gesture.view.transform, scale, scale) 

    } 
    }