IOS Beginner-gestures

I. To learn gestures, first set up an object to operate, we take a photo as an example. First create a ImageView

1. Declare a property:

@property (nonatomic, retain) Uiimageview *imageview;

2. Start a Real object creation

Self.imageview = [[Uiimageview alloc]initwithimage:[uiimage imagenamed:@ "beautiful.jpg"]];

Self.imageView.frame = CGRectMake (100, 200, 200, 300);

[Self.view AddSubview:self.imageView];

[_imageview release];

3. If you want to create a view, open the Picture user interaction feature, by default, no

self.imageView.userInteractionEnabled = YES;

Two, a few common methods of gesture

1. Click events

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initwithtarget:self action: @selector (tapaction:)];// Initialize method, add click Method named Tapaction:

[Self.imageview addgesturerecognizer:tap];//adds gestures to the specified view

[Tap release];

tap.numberoftouchesrequired = 2;//set several finger taps to respond

tap.numberoftapsrequired = 2;//Set a few consecutive clicks to respond

click Method

-(void) Tapaction: (UITapGestureRecognizer *) tap

{

NSLog (@ "I was clicked");

}

2. Long Press Events

Uilongpressgesturerecognizer *longpress = [[Uilongpressgesturerecognizer alloc]initwithtarget:self Action: @selector (longpressaction:)];//the same add event with the event named Longpressaction:

[Self.imageview addgesturerecognizer:longpress];//to add gestures to ImageView

[Longpress release];

Longpress.minimumpressduration = 1;//Set long press trigger time

-(void) Longpressaction: (UITapGestureRecognizer *) longpressaction

{

if (longpressaction.state = = Uigesturerecognizerstatebegan) {

NSLog (@ "Long Press to start");

}

}

3. Rotate

Uirotationgesturerecognizer *rotation = [[Uirotationgesturerecognizer alloc]initwithtarget:self Action: @selector ( Rotationaction:)];

[Self.imageview addgesturerecognizer:rotation];

[Rotation release];

The above method of creation is the previous two methods.

-(void) Rotationaction: (Uirotationgesturerecognizer *) rotationaction{

You can use gestures to know that gestures are added to that view

Uiimageview *imageview = (Uiimageview *) Rotationaction.view;

Find the view and let the view rotate

Imageview.transform = Cgaffinetransformrotate (Imageview.transform, rotationaction.rotation);

rotationaction.rotation = 0;

}

4. Zoom function

Uipinchgesturerecognizer *pinch = [[Uipinchgesturerecognizer alloc] initwithtarget:self action: @selector (pinch:)];

[Self.imageview Addgesturerecognizer:pinch];

[Pinch release];

-(void) Pinch: (Uipinchgesturerecognizer *) pinch

{

Find a view with gestures

Uiimageview *imageviews = (Uiimageview *) Pinch.view;

Find the view to zoom in or zoom in on the view

Imageviews.transform = Cgaffinetransformscale (Imageviews.transform, Pinch.scale, Pinch.scale);

Pinch.scale = 1;

}

5. Drag and drop gestures

Uipangesturerecognizer *tuozhuai = [[Uipangesturerecognizer alloc] initwithtarget:self action: @selector (Tuozhuai:)];

[Self.imageview Addgesturerecognizer:tuozhuai];

[Tuozhuai release];

-(void) Tuozhuai: (Uipangesturerecognizer *) Tuozhuai

{

Find a view with gestures

Uiimageview *imageview = (Uiimageview *) Tuozhuai.view;

Use gestures to get moving points

Cgpoint p = [Tuozhuai Translationinview:imageview];

Cgpoint p = [Tuozhuai Trans:imageview];

Drag and drop via position transform

Imageview.transform = Cgaffinetransformtranslate (Imageview.transform, p.x, P.Y);

[Tuozhuai Settranslation:cgpointzero Inview:imageview];

}

6. Sweep gesture, this gesture is to look at your sliding direction

Uiswipegesturerecognizer *qingsao = [[Uiswipegesturerecognizer alloc]initwithtarget:self Action: @selector (Qingsao:) ];

[Self.view Addgesturerecognizer:qingsao];

[Qingsao release];

Qingsao.direction = Direction of uiswipegesturerecognizerdirectionleft;//sweep

-(void) Qingsao: (Uiswipegesturerecognizer *) Qingsao

{

if (qingsao.direction = = Uiswipegesturerecognizerdirectionleft) {

NSLog (@ "sweep to the Left");

}

}

IOS Beginner-gestures