Reusable Waterfall Stream View

STEP1 = = = Package Custom Uiscrollview Controller

1 Protocol Proxy method

1>> Data Source Proxy Pollscrolldatasource @protocol pollscrolldatasource <nsobject>@required//Returns the total number of columns- (Nsinteger) Numberofcolums: (Uiscrollview*) Jrscroll;//Returns the total number of cells- (Nsinteger) Numberofcells: (Uiscrollview*) Jrscroll;//Returns the actual width height of each cell- (cgsize) Sizeofcellinscroll: (Uiscrollview*) Jrscroll Cellatindex: (Nsinteger) index;//Return to Cell view- (UIView*) Jrscroll: (Uiscrollview*) Jrscroll Cellatindex: (Nsinteger) index;@end2>> Property Agent Pollscrolldelegate @protocol pollscrolldelegate <nsobject>@optional//Return line spacing- (CGFloat) Rowofscroll: (Uiscrollview*) Jrscroll Spaceforcellwithflag: (pollscrollspace) Jrspace;@end3>> Define Agents@property(nonatomic,Weak)ID<PollScrollDataSource> Polldatasource;@property(nonatomic,Weak)ID<PollScrollDelegate> polldelegate;

2 Waterfall Flow view, calculating the location size of each cell

1>> each cell size location obtained by the proxy method//enum type set margin#define KSpacetypedef enum{Topscrollspace,//Top marginBottomscrollspace,//Bottom marginLeftscrollspace,//Left marginRightscrollspace,//Right marginRowscrollspace,//Row marginsColumnscrollspace//Column margins}pollscrollspace;//Get the total number of cells    Nsintegertotalcell=[ Self. PolldatasourceNumberofcells: Self];//Gets the total number of columns--if column = 0, returns the default value of 3    Nsintegertotalcolum=[ Self. PolldatasourceNumberofcolums: Self];if(!totalcolum) {totalcolum=3; }//Get up, down, left, right, row, column spacing---if there is no response to implement the Proxy method, set the default value    CGFloatTopspace=kspace,bottomspace=kspace,leftspace=kspace,rightspace=kspace,rowspace=kspace,columnspace=kspace;if([ Self. PolldelegateRespondstoselector:@selector(Rowofscroll:spaceforcellwithflag:)]) {topspace=[ Self. PolldelegateRowofscroll: SelfSpaceforcellwithflag:topscrollspace]; bottomspace=[ Self. PolldelegateRowofscroll: SelfSpaceforcellwithflag:bottomscrollspace]; leftspace=[ Self. PolldelegateRowofscroll: SelfSpaceforcellwithflag:leftscrollspace]; rightspace=[ Self. PolldelegateRowofscroll: SelfSpaceforcellwithflag:rightscrollspace]; rowspace=[ Self. PolldelegateRowofscroll: SelfSpaceforcellwithflag:rowscrollspace]; columnspace=[ Self. PolldelegateRowofscroll: SelfSpaceforcellwithflag:columnscrollspace]; }CGFloatCoorarray[totalcolum]; for(intI=0; i<totalcolum; i++) {//re-initialize the arraycoorarray[i]=0; } for(intI=0;i<totalcell; i++) {//Calculate all frame        //Find the lowest location        CGFloatheight=coorarray[0];Nsintegerindex=0; for(intj=0; j<totalcolum; J + +) {if(Coorarray[j] < height)                {HEIGHT=COORARRAY[J];            Index=j; }        }//Calculate frame        //Get the actual width and height of the image, which is the actual width and height obtained from the plist        cgsizeframe=[ Self. PolldatasourceSizeofcellinscroll: SelfCELLATINDEX:I];//Set the width and height of each cell         Self. Cellwidth=(( Self. Frame. Size. Width-leftspace-rightspace)-columnspace* (totalcolum-1))/totalcolum; Self. Cellheight= Self. Cellwidth*frame. Height/frame. Width;//w h determines the width by spacing, and then scales to get the height        //spacing between adjacent cells        CGFloatVspace= Self. Cellheight+rowspace;distance between//two vertical cells        CGFloatHspace= Self. Cellwidth+columnspace;//Two horizontal cell distance  //where each cell is located        CGRectFrames=cgrectmake (Index*hspace+leftspace,height+rowspace, Self. Cellwidth, Self. Cellheight); Nsvalue * Value=[nsvalue Valuewithcgrect:frames];// update array DataCoorarray[index]=cgrectgetmaxy (frames); [ Self. FramearrayAddobject:value]; }//Get the maximum height    CGFloatmaxheight=coorarray[0]; for(intj=0; j<totalcolum; J + +) {if(Coorarray[j]>maxheight)        {MAXHEIGHT=COORARRAY[J]; }    } Self. Contentsize=cgsizemake (0, maxheight+Ten);

3 Waterfall flow views that can be reused

1>> Render Waterfall Stream View Method-(void) layoutsubviews{[SuperLayoutsubviews]; for(intI=0; i< Self. Framearray. Count; i++) {Nsvalue * value= Self. Framearray[i];CGRectFrame=[value Cgrectvalue];BOOLisinscreen=[ Self_isinscreen:frame];if(Isinscreen) {//On the screen there are two situations---1> have been added before (do not process)--2> just entered the screen (join the dictionary)            if(! Self. Inscreendic[@ (i)]) {//Not appearing on the screen before the join dictionary                UIView* view=[ Self. PolldatasourceJrscroll: SelfCELLATINDEX:I]; View. Frame=frame; [ SelfAddsubview:view];//load to the field of view screen[ Self. InscreendicSetobject:view forkey:@ (i)];//Add to Dictionary}         }Else{//If you leave the screen, remove it from the parent view of the screen and remove it from the dictionary            UIView* cell= Self. Inscreendic[@ (i)];if(Jrcell) {//Join to the cache poolNsmutableset * set= Self. Pooldic[Jrcell. Identy];                [Set Addobject:jrcell]; [Jrcell Removefromsuperview];//Remove from screen[ Self. Inscreendicremoveobjectforkey:@ (i)];//Remove from dictionary}        }    }}2>> Judging is not on the screen-(BOOL) _isinscreen: (CGRect) frame{CGFloatcontenty= Self. Contentoffset. Y;BOOLCondition=cgrectgetmaxy (frame) >contenty && frame. Origin. Y<contenty+ Self. Frame. Size. Height;returncondition;}

4 Getting a cell view that can be reused

- (UIView *)dequeueReuseCellWithIdenty:(NSString *)identy{    set=self.poolDic[identy];    if (set==nil) {        set=[NSMutableSet set];        [self.poolDic setObject:set forKey:identy];    }    UIView * view=[set anyObject];    if (view) {        [set removeObject:view];    }    return view;}

Step2 = = = Waterfall Stream implementation

1>> Load data (plist file)-(void) _loaddata{//Get data into array from plist    NSString* path=[[NSBundlemainbundle]pathforresource:@"File.plist"OfType:Nil]; Self. DataArray=[NsarrayArraywithcontentsoffile:path];}2>> calls the definedUiscrollview, implement Proxy-(void) _loadsubviews{Uiscrollview* scrollview=[[UiscrollviewAlloc]initwithframe: Self. View. Bounds]; ScrollView. Polldatasource= Self; ScrollView. Polldelegate= Self; Self. ScrollView=scrollview; [ Self. ViewAddsubview:scrollview]; }3>> Agent Method#pragma mark-polldatasource//Returns the total number of columns- (Nsinteger) Numberofcolums: (Uiscrollview*) jrscroll{return 3;}//Returns the total number of cells- (Nsinteger) Numberofcells: (Uiscrollview*) jrscroll{return  Self. DataArray. Count;}//Returns the actual width height of each cell- (cgsize) Sizeofcellinscroll: (Uiscrollview*) Jrscroll Cellatindex: (Nsinteger) index{nsdictionary* temdic= Self. DataArray[index]; Self. Width=[temdic[@"W"] Floatvalue]; Self. Height=[temdic[@"H"] Floatvalue];returnCgsizemake ( Self. Width, Self. Height);}//Return to Cell view- (UIView*) Jrscroll: (Uiscrollview*) Jrscroll Cellatindex: (Nsinteger) index{Static NSString* [Email protected]"MyCell";UIView* Cell=[jrscroll Dequeuereusecellwithidenty:identy];//Create a cell that can be recycled repeatedly    if(cell==Nil) {cell=[[UIViewAlloc]initwithreuseidentifier:identy];//NSLog (@ "====>%li", index);}nsdictionary* dic= Self. DataArray[index]; Cell. IMGSRC=dic[@"img"]; Cell. Textlabel. Text=dic[@"Price"];returnCell;}#pragma mark-polldelegate//Return line spacing- (CGFloat) Rowofscroll: (Uiscrollview*) Jrscroll Spaceforcellwithflag: (pollscrollspace) jrspace{Switch(Jrspace) { CaseTopscrollspace:return  -; CaseBottomscrollspace:return Ten; CaseLeftscrollspace:return Ten; CaseRightscrollspace:return Ten; CaseRowscrollspace:return Ten; CaseColumnscrollspace:return Ten;default:return Ten; }}

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Reusable Waterfall Stream View