iOS internal purchase: automatic renewal subscription summary

There are four types of internal purchase: consumer goods, non consumer goods, non renewal subscription and automatic renewal subscription. As the name suggests, the most difficult is the implementation of automatic renewal subscription. After opening automatic renewal subscription, the processing of subscription members will encounter the foll ...

Posted by Chappers on Sun, 26 Sep 2021 08:06:35 +0200

C + + print files -- files and streams

Files and streams Due to the needs of the project, it is required to output the image data to the file after processing. In the file, different kinds of data will be displayed in table layout. At first, it was not easy to do, and then try it 1. Basic knowledge To process files in C + +, you must include header files and in the C + + source ...

Posted by scottb1 on Thu, 23 Sep 2021 09:12:41 +0200

How does iOS development limit the scope of NSNotification

  in actual development, NSNotification can well decouple code and transmit data across layers. But because it is globally effective. Therefore, sometimes we don't want to have such a wide range of functions, but just want to send and receive notifications within a certain range. Recently, I made a plan to share with you. My side is mainly ...

Posted by josephferris on Mon, 20 Sep 2021 19:07:29 +0200

A classical probability problem (probability distribution problem)

A classical probability problem   Competition home page   My submission Time limit: 1 second for C / C + + and 2 seconds for other languages Space limitation: C / C + + 26244k, other languages 524288K 64bit IO Format: %lld Title Description   Students bit noob and lit noob (hereinafter referred to as B and L) of Niuniu univ ...

Posted by clandestine555 on Mon, 20 Sep 2021 12:36:44 +0200

After the APP enters the foreground from the background mode, open the specified page

Requirements: some time ago, when developing a project, there was a requirement. Because some information of the APP is sensitive, if the user presses the home key to return to the background during the operation of the APP, after the specified time, and then switches to the foreground, it is necessary to verify the fingerprint or gesture set b ...

Posted by SystemWisdom on Sun, 19 Sep 2021 11:41:00 +0200

iOS LeetCode Palindrome Pair

Given a different set of words, find all the different index pairs (i, j) so that two words in the list, words[i] + words[j], can be stitched together into palindrome strings. Example 1: Input: words = ["abcd","dcba","lls","s","sssll"] Output:[[0,1],[1,0],[3,2],[2,4]] Interpretation: A spliceable palindrome string is ["dcbaabcd","abcddcba"," ...

Posted by Helios on Sat, 18 Sep 2021 22:04:25 +0200

iOS underlying principle 26: principle of lock

This paper mainly introduces the common locks and the underlying analysis of synchronized, NSLock, recursive lock and conditional lock   lock Refer to the performance data comparison diagram of a lock, as shown below Lock performance comparison It can be seen that the lock performance in the figure is from high to low: osspinlock - > d ...

Posted by gregzor on Sun, 12 Sep 2021 21:59:33 +0200

Crawl app photos with python

Download a fighting fish first (you can do it without downloading, the URLs are all here, right) Grab a json package by grabbing it and get the address below   Observed tests show that modifying offset values is equivalent to paging an app Accessing this url returns a large dictionary with two indexes, one error and one data.Data is another 20 ...

Posted by djcubez on Mon, 20 Jul 2020 16:59:48 +0200

Summary: Classic crash of multithreading in iOS

preface iOS crash is a headache for iOS developers. App crashes, indicating that there is a problem in code writing. It is very important to quickly locate the crash site. It's easier to find the problem in the debugging phase, but it's more troublesome to analyze the crash report of the app that has been launched. This article will summarize a ...

Posted by darksniperx on Mon, 22 Jun 2020 09:02:04 +0200

Analysis of 5000 word react native source code

Write at the beginning Recently, the official account of React-native is the main attack. By the way, I will review the next React-native. Node.js And cross platform direction, architecture and Debug If you are interested in the proposal, we should recommend the following official account. https://mp.weixin.qq.com/s/RsvI5AFzbp3rm6sOlTmiYQ Of ...

Posted by godfrank on Mon, 22 Jun 2020 06:32:47 +0200