ios - Why a subView won't stay in the parent frame? -


i have view , inside there's uiimage. image isn't static , can move around if drag finger around (using drag events) problem picture moves outside of uiview frame. what's appropriate way keep inside parent frame bounds?

--uiviewa

--------uiviewb

--------------uiimage

--------------uibutton

i want keep uiimage inside uiviewb

- (ibaction)mybuttonsingletap:(uibutton *)sender {     imdragging = yes;     [_mybutton addtarget:self action:@selector(dragbegan:withevent:) forcontrolevents: uicontroleventtouchdown];  }  - (ibaction)mybuttondraginside:(uibutton *)sender {     [_mybutton addtarget:self action:@selector(draging:withevent:) forcontrolevents: uicontroleventtouchdraginside];  } - (void)dragbegan:(uicontrol *)c withevent:ev {      uitouch *touch = [[ev alltouches] anyobject];     startingtouchpoint = [touch locationinview:self.view];  } - (void)draging:(uicontrol *)c withevent:ev {     uitouch *touch = [[ev alltouches] anyobject];     currenttouchpoint = [touch locationinview:self.view];     _movingpic.frame = cgrectmake(currenttouchpoint.x, currenttouchpoint.y, 28, 23); }

you need check location of view during dragging.

at point setting frame of image depending on user's drag direction, etc...

during should have logic check like...

if new location x value less 0 set new location x = 0. if new location x value plus image width greater view width set new location x = view width - image width.

etc...

then use new location point move image to.


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