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How to convert a string into double and vice versa?
... Double is a numeric data type - it does not contain any formatting. Calling [NSString doubleValue] would return 1000 because it's just a number.
– Andy
Oct 5 '08 at 12:53
12
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getting type T from IEnumerable
... Or even worse write a method with yield returns and try to call GetType on a variable created with this method. It will tell you that it is not event a generic type. So basically there is no universal way to get T given an instance variable of type IEnumerable<T>
...
Unbalanced calls to begin/end appearance transitions for
...e not-suitable (like during initialization) procedure finishes, by doing:
__weak MyViewController *weakSelf = self;
dispatch_async(dispatch_get_main_queue(), ^{
[weakSelf presentViewController:vc animated:YES];
});
This is general for also pushViewController:animated:, etc.
...
Swift: declare an empty dictionary
...ou have to be explicit, otherwise you will produce an unusable instance of __NSDictionaryI. Try adding an element to that emptyDict and it will fail at compile time.
– Gabriele Petronella
Jun 4 '14 at 13:34
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Setting UIButton image results in blue button in iOS 7
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In iOS7 there is new button type called UIButtonTypeSystem NS_ENUM_AVAILABLE_IOS(7_0), // standard system button
Check your .xib file and change button type to Custom
To do this programmatically, add this line to the viewDidLoad:
[UIButton buttonWithType...
Sending a message to nil in Objective-C
...I wonder what " sending a message to nil " means - let alone how it is actually useful. Taking an excerpt from the documentation:
...
What is the difference between HAVING and WHERE in SQL?
...nt(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities in MA with more than 5 address...
ImageUtil 扩展：图像工具扩展，提供图像处理和变换功能 · App Inventor 2 中文网
...
当 保存按钮.被点击
设置 保存路径 = "/sdcard/processed_image.jpg"
调用 ImageUtil1.Save 图片组件 保存路径
显示通知 "图像已保存到: " & 保存路径
高级应用
批量图像处理
当 批量处理按钮.被...
How to calculate dp from pixels in android programmatically [duplicate]
I want to calculate dp from px programmatically. How to do it?
I get resolution from:
4 Answers
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How to avoid “Permission denied” when using pip with virtualenv
...ed Oct 19 '13 at 23:02
sebastian_oesebastian_oe
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