IOS via button Click asynchronously Load Picture _ios

Compare the original method:

Copy Code code as follows:

AsyncImageView.h:
#import <UIKit/UIKit.h>
@interface Asyncimageview:uiview
{
nsurlconnection* connection;
nsmutabledata* data;
}
-(void) Loadimagefromurl: (nsurl*) URL;
@end
ASYNCIMAGEVIEW.M:
#import "AsyncImageView.h"
@implementation Asyncimageview
-(ID) initWithFrame: (CGRect) frame
{
self = [super Initwithframe:frame];
if (self) {
Initialization code
}
returnself;
}
-(void) Loadimagefromurl: (nsurl*) URL {
if (connection!=nil) {[Connection release];}
if (data!=nil) {[Data release];}
nsurlrequest* request = [Nsurlrequest Requestwithurl:url
Cachepolicy:nsurlrequestuseprotocolcachepolicy
timeoutinterval:60.0];
connection = [[Nsurlconnection alloc]
Initwithrequest:request Delegate:self];
}
-(void) connection: (Nsurlconnection *) theconnection
Didreceivedata: (NSData *) Incrementaldata {
if (Data==nil) {
data =
[[Nsmutabledata alloc] initwithcapacity:2048];
}
[Data Appenddata:incrementaldata];
}
-(void) connectiondidfinishloading: (nsurlconnection*) theconnection {
[Connection release];
Connection=nil;
if ([[Self subviews] count] > 0) {
[[[Self subviews] objectatindex:0] removefromsuperview];
}
Uiimageview *imageview = [[[[Uiimageview alloc] initwithimage:[uiimage Imagewithdata:data]] autorelease];
Imageview.contentmode = Uiviewcontentmodescaleaspectfit;
Imageview.autoresizingmask = (Uiviewautoresizingflexiblewidth | Uiviewautoresizingflexibleheight);
[Self addsubview:imageview];
Imageview.frame = Self.bounds;
[ImageView Setneedslayout];
[Self setneedslayout];
[Data release];
Data=nil;
}
-(uiimage*) Image {
uiimageview* IV = [[self subviews] objectatindex:0];
Return[iv image];
}
-(void) Dealloc {
[Connection Cancel];
[Connection release];
[Data release];
[Super Dealloc];
}
@end

Method Two:

Copy Code code as follows:

@interface UIButton (Asyncimage)
Size by point
-(void) Setimagefromurl: (NSString *) urlstring adjusttosize: (cgsize) Size completion: (void (^) (void) Completion Logo: ( UIImage *) Logoimage;
@end
@implementation UIButton (Asyncimage)
-(void) Setimagefromurl: (NSString *) urlstring adjusttosize: (cgsize) Size completion: (void (^) (void) Completion Logo: ( UIImage *) Logoimage
{
Dispatch_async (Dispatch_get_global_queue (dispatch_queue_priority_default, 0), ^{
UIImage *image = nil;
Nsurl *url = [Nsurl urlwithstring:urlstring];
NSData *data = [NSData Datawithcontentsofurl:url];
Image = [UIImage imagewithdata:data];
if (image) {
if (! Cgsizeequaltosize (size, Cgsizezero)) {
Image = [UIImage imagewithcgimage:image. Cgimage scale:[self scaleimage:image adjusttosize:size] orientation:image.imageOrientation];
}
if (logoimage) {
Image = [self addlogoimage:logoimage toimage:image];
}
Dispatch_async (Dispatch_get_main_queue (), ^{
[Self setimage:image forstate:uicontrolstatenormal];
Completion ();
});
}
else {
NSLog (@ "Async load error.");
}
});
}
Scale pictures to fit button size
-(CGFloat) Scaleimage: (UIImage *) image adjusttosize: (cgsize) size
{
CGFloat XScale = size.width/image.size.width;
CGFloat Yscale = size.height/image.size.height;
Return 1.0/min (XScale, Yscale);
}
-(UIImage *) Addlogoimage: (UIImage *) logo toimage: (uiimage *) img
{
Get image width and height
CGFloat scale = [UIScreen mainscreen].scale;
int w = scale * img.size.width;
int h = scale * img.size.height;
int logowidth = Logo.scale * logo.size.width;
int logoheight = Logo.scale * logo.size.height;
Cgcolorspaceref colorspace = Cgcolorspacecreatedevicergb ();
Create a graphic context with cgbitmapcontextcreate
Cgcontextref context = Cgbitmapcontextcreate (NULL, W, H, 8, 4 * W, colorspace, Kcgimagealphapremultipliedfirst);
Cgcontextdrawimage (context, CGRectMake (0, 0, W, h), IMG. Cgimage);
Cgcontextdrawimage (Context, CGRectMake (w-logowidth, 0, Logowidth, logoheight), [logo cgimage]);
Cgimageref imagemasked = cgbitmapcontextcreateimage (context);
Cgcontextrelease (context);
Cgcolorspacerelease (ColorSpace);
return [UIImage imagewithcgimage:imagemasked Scale:scale orientation:img.imageOrientation];
}
@end

Method Three:

#import <Foundation/Foundation.h>
#import "StringUtils.h"

@interface imagemanager:nsobject
{
  nsmutabledictionary *_imagedict;
  Nsmutablearray *_imagearr;
}

@property (nonatomic, strong) NSString *httpurl;
@property (nonatomic, strong) nsmutabledictionary *imagedict;

@property (nonatomic, assign) dispatch_queue_t Networkqueue;

+ (Imagemanager *) sharedinstance;


-(void) Asyncimage: (NSString *) imagename ImageView: (Uiimageview *) ImageView;
Queue
-(void) Asyncimageinsert: (NSString *) imagename ImageView: (Uiimageview *) ImageView Insert: (BOOL) insert;
Do not download data before downloading
-(void) Asyncimagecleanold: (NSString *) imagename ImageView: (Uiimageview *) ImageView Cleanold: ( BOOL) Cleanold;

@end

Implementation file:

IMAGEMANAGER.M//Myb-ios////Created by Warrior Gao on 13-6-5. Copyright (c) 2013 51myb.
All rights reserved. #import "ImageManager.h" @interface Imagemanager () @end The maximum number of @implementation Imagemanager//cache of a picture, static int Counte

R = 0;

@synthesize imagedict = _imagedict;
  Singleton + (Imagemanager *) sharedinstance {static ID instance;
  Static dispatch_once_t Oncetoken;
  Dispatch_once (&oncetoken, ^{instance = self.new;
  });
return instance;  }-(ID) init {if ((self = [super init]) {self.networkqueue = Dispatch_queue_create ("Com.warrior.network.image"),
    NIL);
    _imagedict = [[Nsmutabledictionary alloc] init];
  _imagearr = [[Nsmutablearray alloc] init];
return self; }-(NSString *) Filefullpath: (NSString *) fileName {nsstring *cachepath = [Nssearchpathfordirectoriesindomains (NSCache
  
  Sdirectory, Nsuserdomainmask, YES) objectatindex:0];
  
  NSString *filefullpath = [NSString stringwithformat:@ "%@/%@", Cachepath,filename]; RetUrn Filefullpath; //Do not before downloading data-(void) Asyncimagecleanold: (NSString *) imagename ImageView: (Uiimageview *) ImageView cleanold: (BOOL)
  Cleanold {if (cleanold) {[_imagearr removeallobjects];
[Self asyncimage:imagename imageview:imageview]; }//Queue up, priority-(void) Asyncimageinsert: (NSString *) imagename ImageView: (Uiimageview *) ImageView Insert: (BOOL) Insert {if (S
  Tringutils Isempty:imagename]) {return; } nsdata *data = [NSData datawithcontentsoffile:[self filefullpath:[imagename stringbyreplacingoccurrencesofstring:@ "
  /"withstring:@"-"]"];
    if (data = = nil) {[_imagedict setvalue:imageview forkey:imagename];
    if (insert) {[_imagearr insertobject:imagename atindex:0];
    else {[_imagearr addobject:imagename];
  } [self cacheimage];
  else {[ImageView setimage:[uiimage imagewithdata:data]]; }//Normal, Append to back-(void) Asyncimage: (NSString *) imagename ImageView: (Uiimageview *) ImageView {[Self Asyncimageinsert:ima GeName Imageview:imageview Insert:no]; ///Async cache picture to local, up to two threads-(void) Cacheimage {for (; counter < 2 && _imagearr.count > 0; counter++) {N
    Sstring *imagename = nil;
      @synchronized (self) {imagename = [[_imagearr objectatindex:0] copy];
    [_imagearr removeobjectatindex:0];
    
    } if (imagename = = nil) continue;
      Dispatch_async (Self.networkqueue, ^{NSLog (@ "Starting:%@", imagename);
      UIImage *avatarimage = nil;
      Nsurl *url = [Nsurl urlwithstring:[nsstring stringwithformat:@ "%@%@", Self.httpurl, ImageName]];
      NSData *responsedata = [NSData Datawithcontentsofurl:url]; if (Responsedata.length > 0) {[ResponseData writetofile:[self filefullpath:[imagename Stringbyreplacingoc
        currencesofstring:@ "/" withstring:@ "-"]] atomically:no];
        Avatarimage = [UIImage imagewithdata:responsedata];
        
        NSLog (@ "Finishing:%@", imagename); if (avatarimage) {Dispatch_async (dispAtch_get_main_queue (), ^{uiimageview *imageview = [_imagedict objectforkey:imagename];
            if (ImageView!= nil && avatarimage!= nil) {[ImageView setimage:avatarimage];
            } [_imagedict Removeobjectforkey:imagename];
          [ImageName release];
        });
      }} counter--;
    [Self cacheimage];
    
  }); }} @end

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