iOS 通过collectionView实现照片删除功能

#import <uikit/uikit.h>
@interface viewcontroller : uiviewcontroller
<uicollectionviewdatasource,uicollectionviewdelegate,uicollectionviewdelegateflowlayout,uialertviewdelegate,uiactionsheetdelegate,uiimagepickercontrollerdelegate,uinavigationcontrollerdelegate>
{
 uicollectionview *_collectionview;
 uiimagepickercontroller *_imagepicker;
 nsmutablearray *photos;
 nsmutablearray *dataarray;
 nsinteger deleteindex;
 bool wobble;
}
@end

//点击添加按钮的时候，停止删除。
#import "viewcontroller.h"
#import "photocollectionviewcell.h"
nsinteger const photo = 8;
@interface viewcontroller ()
@end
@implementation viewcontroller
- (void)viewdidload {
 [super viewdidload];
 // do any additional setup after loading the view, typically from a nib.
 //其布局很有意思，当你的cell设置大小后，一行多少个cell，由cell的宽度决定
 uicollectionviewflowlayout *flowlayout = [[uicollectionviewflowlayout alloc]init];
 //设置cell的尺寸
 [flowlayout setitemsize:cgsizemake(70, 70)];
 //设置其布局方向
 [flowlayout setscrolldirection:uicollectionviewscrolldirectionvertical];
 //设置其边界(上，左，下，右）
 flowlayout.sectioninset = uiedgeinsetsmake(5,5,5,5);
 _collectionview = [[uicollectionview alloc]initwithframe:cgrectmake(10, 50, 320,85*2) collectionviewlayout:flowlayout];
 _collectionview.datasource = self;
 _collectionview.delegate = self;
 _collectionview.backgroundcolor = [uicolor redcolor];
 [_collectionview registerclass:[photocollectionviewcell class] forcellwithreuseidentifier:@"photo"];
 [self.view addsubview:_collectionview];
 photos = [[nsmutablearray alloc ] init];
 dataarray = [[nsmutablearray alloc ] init];
 [dataarray addobject:[uiimage imagenamed:@"contract_addpic1"]];
}
//section
- (nsinteger)numberofsectionsincollectionview:(uicollectionview *)collectionview
{
 return 1;
}
//item个数
- (nsinteger)collectionview:(uicollectionview *)collectionview numberofitemsinsection:(nsinteger)section
{
 return dataarray.count;
}
-(uicollectionviewcell *)collectionview:(uicollectionview *)collectionview cellforitematindexpath:(nsindexpath *)indexpath
{
 nslog(@"--indexpath.row--%ld",indexpath.row);
 nslog(@"---indexpath.section--%ld",indexpath.section);
 photocollectionviewcell *cell = (photocollectionviewcell *)[collectionview dequeuereusablecellwithreuseidentifier:@"photo" forindexpath:indexpath];
 cell.tag=indexpath.row;
 //图片
 cell.photoimage.image=dataarray[indexpath.row];
 // 删除按钮
 cell.deletebtn.tag =indexpath.row;
 cell.deletebtn.hidden=yes;
 [cell.deletebtn addtarget:self action:@selector(doclickdeletebutton:) forcontrolevents:uicontroleventtouchupinside];
 //增加按钮
 if (indexpath.row == dataarray.count -1) {
  cell.addbtn.hidden = no;
 }else
 {
  cell.addbtn.hidden = yes;
 }
 [cell.addbtn addtarget:self action:@selector(doclickaddbutton:) forcontrolevents:uicontroleventtouchupinside];
 // 长按删除
 uilongpressgesturerecognizer *longpress = [[uilongpressgesturerecognizer alloc ] initwithtarget:self action:@selector(longpressedaction)];
 [cell.contentview addgesturerecognizer:longpress];
 return cell;
}
#pragma -mark -doclickactions
//删除按钮
-(void)doclickdeletebutton:(uibutton *)btn
{
 nslog(@"-----doclickdeletebutton-------");
 uialertview *alert = [[uialertview alloc ] initwithtitle:@"提示" message:@"您确定要删除吗？" delegate:self cancelbuttontitle:@"取消" otherbuttontitles:@"确定", nil];
 deleteindex = btn.tag;
 [alert show];
 nslog(@"---delete--dataarray---%@",dataarray);
}
//增加按钮
-(void)doclickaddbutton:(uibutton *)btn
{
 nslog(@"-----doclickaddbutton-------");
 if (wobble) {
  // 如果是编辑状态则取消编辑状态
  [self cancelwobble];
 }else{
  //不是编辑状态，添加图片
  if (dataarray.count > photo) {
   uialertview *alert = [[uialertview alloc ] initwithtitle:@"提示" message:@"最多支持8个" delegate:self cancelbuttontitle:@"取消" otherbuttontitles:@"确定", nil];
   [alert show];
  }else
  {
   uiactionsheet *actionsheet = [[uiactionsheet alloc]
           initwithtitle:nil
           delegate:(id)self
           cancelbuttontitle:@"取消"
           destructivebuttontitle:nil
           otherbuttontitles:@"拍照", @"我的相册",nil];
   actionsheet.actionsheetstyle = uiactionsheetstyleblackopaque;
   [actionsheet showinview:self.view];
  }
 }
 nslog(@"---add--dataarray---%@",dataarray);
}
//长按删除
-(void)longpressedaction
{
 nslog(@"-----longpressedaction-------");
 wobble = yes;
 nsarray *array = [_collectionview subviews];
 for (int i = 0; i < array.count; i ++) {
   if ([array[i] iskindofclass:[photocollectionviewcell class]]) {
   photocollectionviewcell *cell = array[i];
   if (cell.addbtn.hidden) {
    cell.deletebtn.hidden = no;
   }
   else
   {
    cell.deletebtn.hidden = yes;
    cell.photoimage.image = [uiimage imagenamed:@"ensure"];
    cell.tag = 999999;
   }
   // 晃动动画
   [self animationviewcell:cell];
  }
 }
}
// 取消晃动
-(void)cancelwobble
{
 wobble = no;
 nsarray *array = [_collectionview subviews];
 for (int i = 0; i < array.count; i ++) {
  if ([array[i] iskindofclass:[photocollectionviewcell class]]) {
   photocollectionviewcell *cell = array[i];
   cell.deletebtn.hidden = yes;
   if (cell.tag == 999999) {
    cell.photoimage.image = [uiimage imagenamed:@"plus"];
   }
   // 晃动动画
   [self animationviewcell:cell];
  }
 }
}
// 晃动动画
-(void)animationviewcell:(photocollectionviewcell *)cell
{
 //摇摆
 if (wobble){
  cell.transform = cgaffinetransformmakerotation(-0.1);
  [uiview animatewithduration:0.08
        delay:0.0
       options:uiviewanimationoptionrepeat|uiviewanimationoptionautoreverse|uiviewanimationoptionallowuserinteraction|uiviewanimationoptioncurvelinear
       animations:^{
        cell.transform = cgaffinetransformmakerotation(0.1);
       } completion:nil];
 }
 else{
  [uiview animatewithduration:0.25
        delay:0.0
       options:uiviewanimationoptionallowuserinteraction|uiviewanimationoptionbeginfromcurrentstate|uiviewanimationoptioncurveeaseout
       animations:^{
        cell.transform = cgaffinetransformidentity;
       } completion:nil];
 }
}
#pragma -mark -uiactionsheetdelegate
- (void)actionsheet:(uiactionsheet *)actionsheet clickedbuttonatindex:(nsinteger)buttonindex
{
 if (buttonindex == 0) {
  [self opencamera];
 }else if(buttonindex == 1) {
  [self openpics];
 }
}
#pragma -mark -uialertviewdelegate
- (void)alertview:(uialertview *)alertview clickedbuttonatindex:(nsinteger)buttonindex
{
 if (buttonindex == 1) {
  [dataarray removeobjectatindex:deleteindex];
  nsindexpath *path = [nsindexpath indexpathforrow:deleteindex insection:0];
  [_collectionview deleteitemsatindexpaths:@[path]];
  // 如果删除完，则取消编辑
  if (dataarray.count == 1) {
   [self cancelwobble];
  }
  // 没有删除完，执行晃动动画
  else
  {
   [self longpressedaction];
  }
 }
}
#pragma -mark -camera
// 打开相机
- (void)opencamera {
 if ([uiimagepickercontroller issourcetypeavailable:uiimagepickercontrollersourcetypecamera])
 {
  if (_imagepicker == nil) {
   _imagepicker = [[uiimagepickercontroller alloc] init];
  }
  _imagepicker.delegate = (id)self;
  _imagepicker.sourcetype = uiimagepickercontrollersourcetypecamera;
  _imagepicker.showscameracontrols = yes;
  _imagepicker.allowsediting = yes;
  [self.navigationcontroller presentviewcontroller:_imagepicker animated:yes completion:nil];
 }
}
// 打开相册
- (void)openpics {
 if (_imagepicker == nil) {
  _imagepicker = [[uiimagepickercontroller alloc] init];
 }
 _imagepicker.sourcetype = uiimagepickercontrollersourcetypephotolibrary;
 _imagepicker.allowsediting = yes;
 _imagepicker.delegate = (id)self;
 [self presentviewcontroller:_imagepicker animated:yes completion:null];
}
// 选中照片
- (void)imagepickercontroller:(uiimagepickercontroller *)picker didfinishpickingmediawithinfo:(nsdictionary *)info{
 nsstring *mediatype = [info objectforkey:uiimagepickercontrollermediatype];
 [_imagepicker dismissviewcontrolleranimated:yes completion:null];
 _imagepicker = nil;
 // 判断获取类型：图片
 if ([mediatype isequaltostring:@"public.image"]){
  uiimage *theimage = nil;
  // 判断，图片是否允许修改
  if ([picker allowsediting]){
   //获取用户编辑之后的图像
   theimage = [info objectforkey:uiimagepickercontrollereditedimage];
  } else {
   // 照片的元数据参数
   theimage = [info objectforkey:uiimagepickercontrolleroriginalimage] ;
  }
  [dataarray insertobject:theimage atindex:0];
  nsindexpath *path = [nsindexpath indexpathforrow:0 insection:0];
  [_collectionview insertitemsatindexpaths:@[path]];
 }
}
- (void)imagepickercontrollerdidcancel:(uiimagepickercontroller *)picker {
 [picker dismissviewcontrolleranimated:yes completion:null];
}
// 判断设备是否有摄像头
- (bool) iscameraavailable{
 return [uiimagepickercontroller issourcetypeavailable:uiimagepickercontrollersourcetypecamera];
}
#pragma mark - 相册文件选取相关
// 相册是否可用
- (bool) isphotolibraryavailable{
 return [uiimagepickercontroller issourcetypeavailable: uiimagepickercontrollersourcetypephotolibrary];
}
- (void)didreceivememorywarning {
 [super didreceivememorywarning];
 // dispose of any resources that can be recreated.
}
@end

#import <uikit/uikit.h>
@interface photocollectionviewcell : uicollectionviewcell
@property (weak, nonatomic) iboutlet uibutton *addbtn;
@property (weak, nonatomic) iboutlet uiimageview *photoimage;
@property (weak, nonatomic) iboutlet uibutton *deletebtn;
@end

#import "photocollectionviewcell.h"
@implementation photocollectionviewcell
- (id)initwithframe:(cgrect)frame
{
 self = [super initwithframe:frame];
 if (self)
 {
  // 初始化时加载collectioncell.xib文件
  nsarray *arrayofviews = [[nsbundle mainbundle] loadnibnamed:@"photocollectionviewcell" owner:self options:nil];
  // 如果路径不存在，return nil
  if (arrayofviews.count < 1)
  {
   return nil;
  }
  // 如果xib中view不属于uicollectionviewcell类，return nil
  if (![[arrayofviews objectatindex:0] iskindofclass:[uicollectionviewcell class]])
  {
   return nil;
  }
  // 加载nib
  self = [arrayofviews objectatindex:0];
 }
 return self;
}
- (void)awakefromnib {
 // initialization code
}
@end