多工筆記 (GCD)

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UIButton custom font vertical alignment

我在專案裡面用了客制化的字體
發現我的UIButton的字不在正中間


上網查到許多方法
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最後我使用了最簡單的方法
yourButton.contentEdgeInsets = UIEdgeInsetsMake(5, 0, 0, 0);

ios-tips-custom-fonts

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首先先把.ttf檔放進專案裡

確定有勾選Add to targets


Verify the font is in the project. There are two places you can do this.

By selecting the font, and verifying “Target Membership” in the Utilities area.



And By selecting your apps target, selecting the “Build Phases” tab, and verifying that your font is in the “Copy Bundle Resources” section.



And finally, add the font to your Info.plist. Note that most apps change the name of their plist to something like -Info.plist. Add a key of “Fonts provided by application”, and make sure it’s an array, then add your font file name as an item in the array. Make sure you use the exact file name, and that your file name has an all-lowercase extension (.TTF apparently doesn’t work on iPhones, but .ttf does).



Knowing your font
This is where I had some issues. When you add your font you use the file name, but when you use your font you use the font name… The EXACT font name. If you ctrl + click on the .ttf file and select “Get Info”, you can find the “Full Name”. That seems to work with a lot of fonts, but the font I’m using doesn’t work that way. I had to open the .ttf file in the Font Book application, and look at the window header.



Using this name, you can log what font names you have available by using the fontNamesForFamilyName method like so:

NSLog(@"tt0001m_: %@", [UIFont fontNamesForFamilyName:@"Swis721 Lt BT"] ); Which gives the output: 2012-08-24 11:25:10.968 GenericKeychain[7260:c07] tt0001m_: ( "Swiss721BT-Light" )
Using your font programmatically
Say you have a UILabel:

UILabel *myLabel = [[UILabel alloc] init];
[myLabel setText:@"Label Text"];

We set the font of our label by creating a UIFont, and setting it to our label with setFont.
UIFont *swissLight = [UIFont fontWithName:@"Swiss721BT-Light" size:myLabel.font.pointSize]; [myLabel setFont:swissLight];

GCD全称为Grand Central Dispatch dispatch_async

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參考lin2


dispatch_async(dispatch_get_gloabal_queue(0, 0), ^{ //加入耗时操作 //...... dispatch_async(dispatch_get_main_queue(), ^{ //更新UI操作 //..... }); });

ios-ALAssetsLibrary获取系统相簿里边的所有照片

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-(void)getImgs{ dispatch_async(dispatch_get_main_queue(), ^{ NSAutoreleasePool *pool = [[NSAutoreleasePoolalloc] init]; ALAssetsLibraryAccessFailureBlock failureblock = ^(NSError *myerror){ NSLog(@"相册访问失败 =%@", [myerrorlocalizedDescription]); if ([myerror.localizedDescription rangeOfString:@"Global denied access"].location!=NSNotFound) { NSLog(@"无法访问相册.请在'设置->定位服务'设置为打开状态."); }else{ NSLog(@"相册访问失败."); } }; ALAssetsGroupEnumerationResultsBlock groupEnumerAtion = ^(ALAsset *result,NSUInteger index, BOOL *stop){ if (result!=NULL) { if ([[result valueForProperty:ALAssetPropertyType]isEqualToString:ALAssetTypePhoto]) { NSString *urlstr=[NSString stringWithFormat:@"%@",result.defaultRepresentation.url];//图片的url /*result.defaultRepresentation.fullScreenImage//图片的大图 result.thumbnail //图片的缩略图小图 // NSRange range1=[urlstr rangeOfString:@"id="]; // NSString *resultName=[urlstr substringFromIndex:range1.location+3]; // resultName=[resultName stringByReplacingOccurrencesOfString:@"&ext=" withString:@"."];//格式demo:123456.png */ [self._dataArray addObject:urlstr]; } } }; ALAssetsLibraryGroupsEnumerationResultsBlock libraryGroupsEnumeration = ^(ALAssetsGroup* group,BOOL* stop){ if (group == nil) { } if (group!=nil) { NSString *g=[NSString stringWithFormat:@"%@",group];//获取相簿的组 NSLog(@"gg:%@",g);//gg:ALAssetsGroup - Name:Camera Roll, Type:Saved Photos, Assets count:71 NSString *g1=[g substringFromIndex:16 ] ; NSArray *arr=[NSArray arrayWithArray:[g1componentsSeparatedByString:@","]]; NSString *g2=[[arr objectAtIndex:0]substringFromIndex:5]; if ([g2 isEqualToString:@"Camera Roll"]) { g2=@"相机胶卷"; } NSString *groupName=g2;//组的name [groupenumerateAssetsUsingBlock:groupEnumerAtion]; } }; ALAssetsLibrary* library = [[ALAssetsLibraryalloc] init]; [libraryenumerateGroupsWithTypes:ALAssetsGroupAll usingBlock:libraryGroupsEnumeration failureBlock:failureblock]; [library release]; [pool release]; }); } //------------------------根据图片的url反取图片－－－－－ ALAssetsLibrary *assetLibrary=[[ALAssetsLibraryalloc] init]; NSURL *url=[NSURLURLWithString:urlStr]; [assetLibrary assetForURL:url resultBlock:^(ALAsset *asset) { UIImage *image=[UIImage imageWithCGImage:asset.thumbnail]; cellImageView.image=image; }failureBlock:^(NSError *error) { NSLog(@"error=%@",error); } ];