Use gestures to scale, rotate, and move Uiimageview

[CPP]View PlainCopy

2. Add all the gestures
4. -(void) Addgesturerecognizertoview: (UIView *) View
6. {
8. //Rotation gestures
10. Uirotationgesturerecognizer *rotationgesturerecognizer = [[Uirotationgesturerecognizer alloc] InitWithTarget:self Action: @selector (Rotateview:)];
12. [View Addgesturerecognizer:rotationgesturerecognizer];
16. //Zoom gesture
18. Uipinchgesturerecognizer *pinchgesturerecognizer = [[Uipinchgesturerecognizer alloc] initwithtarget:self action:@ Selector (Pinchview:)];
20. [View Addgesturerecognizer:pinchgesturerecognizer];
24. //Mobile gestures
26. Uipangesturerecognizer *pangesturerecognizer = [[Uipangesturerecognizer alloc] initwithtarget:self action: @selector ( Panview:)];
28. [View Addgesturerecognizer:pangesturerecognizer];
30. }
34. Handling Rotation gestures
36. -(void) Rotateview: (Uirotationgesturerecognizer *) Rotationgesturerecognizer
38. {
40. UIView *view = Rotationgesturerecognizer.view;
42. if (rotationgesturerecognizer.state = = Uigesturerecognizerstatebegan | | rotationgesturerecognizer.state = = uigesturerecognizerstatechanged) {
44. View.transform = Cgaffinetransformrotate (View.transform, rotationgesturerecognizer.rotation);
46. [Rotationgesturerecognizer setrotation:0];
48. }
50. }
54. Handling Zoom gestures
56. -(void) Pinchview: (Uipinchgesturerecognizer *) Pinchgesturerecognizer
58. {
60. UIView *view = Pinchgesturerecognizer.view;
62. if (pinchgesturerecognizer.state = = Uigesturerecognizerstatebegan | | pinchgesturerecognizer.state = = uigesturerecognizerstatechanged) {
64. View.transform = Cgaffinetransformscale (View.transform, Pinchgesturerecognizer.scale, PinchGestureRecognizer.scale );
66. Pinchgesturerecognizer.scale = 1;
68. }
70. }
74. Handling Drag gestures
76. -(void) Panview: (Uipangesturerecognizer *) Pangesturerecognizer
78. {
80. UIView *view = Pangesturerecognizer.view;
82. if (pangesturerecognizer.state = = Uigesturerecognizerstatebegan | | pangesturerecognizer.state = = uigesturerecognizerstatechanged) {
84. Cgpoint translation = [Pangesturerecognizer TranslationInView:view.superview];
86. [View SetCenter: (Cgpoint) {view.center.x + translation.x, View.center.y + translation.y}];
88. [Pangesturerecognizer Settranslation:cgpointzero InView:view.superview];
90. }
92. }

This only requires a simple call

[CPP]View PlainCopy

1. [Self addgesturerecognizertoview:view];
3. If you're dealing with a picture, don't forget.
4. [ImageView Setuserinteractionenabled:yes];
5. [ImageView Setmultipletouchenabled:yes];

Done.

Specific use:

Define variables inside the. h file

[CPP]View PlainCopy

1. @interface yourviewcontroller:uiviewcontroller<uigesturerecognizerdelegate>
2. {
3. CGFloat Lastscale;
4. CGRect Oldframe; //Save the original size of the picture
5. CGRect Largeframe; //Determine the maximum extent of the image magnification
6. }

and add it to the viewdidload.

[CPP]View PlainCopy

2. -(void) Viewdidload
4. {
6. [Super Viewdidload];
10. Showimgview = [[Uiimageview alloc] Initwithframe:<span class="S1" >CGRectMake</span> (<span  class="S2" >0</span>, <span class="S2" >0</SPAN>, 320, 480)];
12. [Showimgview Setmultipletouchenabled:yes];
14. [Showimgview Setuserinteractionenabled:yes];
16. [Showimgview setimage:[uiimage imagenamed:@"1.jpg"];
20. Oldframe = Showimgview.frame;
22. Largeframe = CGRectMake (0-screensize.width, 0-screensize.height, 3 * oldFrame.size.width, 3 * oldFrame.size.height);
26. [Self addgesturerecognizertoview:showimgview];
28. [Self.view Addsubview:showimgview];

This will enable the

However, this is not enough.

Because the inside of the scale and movement, etc. did not make a corresponding judgment.

Because the code is simple, the extension is also very convenient.

Modified the scaling code, added the restrictions, and other similar

[CPP]View PlainCopy

2. Handling Zoom gestures
4. -(void) Pinchview: (Uipinchgesturerecognizer *) Pinchgesturerecognizer
6. {
8. UIView *view = Pinchgesturerecognizer.view;
10. if (pinchgesturerecognizer.state = = Uigesturerecognizerstatebegan | | pinchgesturerecognizer.state = = uigesturerecognizerstatechanged) {
12. View.transform = Cgaffinetransformscale (View.transform, Pinchgesturerecognizer.scale, PinchGestureRecognizer.scale );
14. if (ShowImgView.frame.size.width < oldFrame.size.width) {
16. Showimgview.frame = Oldframe;
18. //Make the picture smaller than the original
20. }
22. if (ShowImgView.frame.size.width > 3 * oldFrame.size.width) {
24. Showimgview.frame = Largeframe;
26. }
28. Pinchgesturerecognizer.scale = 1;
30. }
32. }

That's good. The maximum and minimum proportions of the picture are guaranteed.

Reference article: http://apluck.iteye.com/blog/1781607

Use gestures to scale, rotate, and move Uiimageview