小编Tom*_*Dev的帖子

addObject后NSMutableArray为空

我想在NSMutableArray中添加一个对象:

NSLog(@"Object text: %@", object.text);
NSLog(@"Object: %@", object);
[appdelegate.objects addObject:object];
NSLog(@"Objects array size: %i", [appdelegate.objects count]);
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这是输出:

Object text: This is the text
Object: <Object: 0x6e762c0>
Objects array size: 0
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这怎么可能,我添加一个对象,在下一行,它仍然是空的.该NSMutableArray不是nil,因为那样会引发异常.

有谁猜?

objective-c nsmutablearray ios

7
推荐指数
1
解决办法
6271
查看次数

Android 6(Marshmallow)Wifi +蓝牙有时会导致SocketTimeoutException

当用户当前正在使用该应用时,我们的Android应用会出现问题,该应用会使用蓝牙扫描信标.应用程序在加载不同视图时从API加载数据.有时,当继续单击视图时,一个请求失败(超时),出现此错误:

java.net.SocketTimeoutException: failed to connect to www.examplehost.com/111.222.333.444 (port 80) after 15000ms
                                              at libcore.io.IoBridge.connectErrno(IoBridge.java:169)
                                              at libcore.io.IoBridge.connect(IoBridge.java:122)
                                              at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:183)
                                              at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:452)
                                              at java.net.Socket.connect(Socket.java:884)
                                              at com.android.okhttp.internal.Platform.connectSocket(Platform.java:117)
                                              at com.android.okhttp.internal.http.SocketConnector.connectRawSocket(SocketConnector.java:434)
                                              at com.android.okhttp.internal.http.SocketConnector.connectCleartext(SocketConnector.java:105)
                                              at com.android.okhttp.Connection.connect(Connection.java:1331)
                                              at com.android.okhttp.Connection.connectAndSetOwner(Connection.java:1410)
                                              at com.android.okhttp.OkHttpClient$1.connectAndSetOwner(OkHttpClient.java:128)
                                              at com.android.okhttp.internal.http.HttpEngine.nextConnection(HttpEngine.java:466)
                                              at com.android.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:447)
                                              at com.android.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:353)
                                              at com.android.okhttp.internal.huc.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:468)
                                              at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:410)
                                              at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getResponseCode(HttpURLConnectionImpl.java:532)
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(这是我们服务器的IP地址,替换为111.222.333.444)

这是一个超时(> 15秒),而之前的请求相当快.

我没有遇到其他设备的这个问题,只有在更新到Android 6.0.1时才能在Samsung S6上使用.因为应用程序位于前台,我认为它不是Doze或Standby(Android 6中的新功能),因为该应用程序正在被积极使用.但是当应用程序处于后台时可能会出现同样的问题(但很难测试).

有没有人知道我们应该在哪里寻找问题?提前致谢.

android bluetooth socket-timeout-exception ibeacon-android android-6.0-marshmallow

3
推荐指数
1
解决办法
1418
查看次数

使用NSNumber的SQLLite查询WHERE在处理params时出现BAD_ACCESS错误

我在为我的iOS应用程序插入一个int到SQLite数据库时遇到问题.当我选择它时,它总是为零.

我正在创建这个表:

CREATE TABLE followedCategory(id TEXT(256) primary key, title TEXT(256), img BLOB, following INTEGER)
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最后一个param(following)导致了问题.我用这段代码插入记录:

DatabaseRecord *rec = [database query:@"INSERT INTO followedCategory VALUES (?1, ?2, ?3, ?4)" params:category.categoryId, category.title, UIImagePNGRepresentation(category.image), [NSNumber numberWithInt:1], nil];
[rec next];
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当我用这个查询表时:

DatabaseRecord *rec = [database query:@"SELECT COUNT(*) FROM followedCategory WHERE following = ?1" params:[NSNumber numberWithInt:1], nil];
[rec next];

return [rec intAtCol:0];
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我总是得到零结果.当我运行这个:

DatabaseRecord *recTest = [database query:@"SELECT following FROM followedCategory LIMIT 2"];
[recTest next];
NSLog(@"First following is %i", [recTest intAtCol:0]);
[recTest next];
NSLog(@"Second …
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sqlite objective-c nsnumber ios

1
推荐指数
1
解决办法
81
查看次数