我试图在Swift中编写一个Mac应用程序,该应用程序通过名为PeerTalk的库与iOS设备进行通信,从http://rsms.me/peertalk/可用,因此我一直试图在Swift中重写PeerTalk示例项目。我的Swift重写正确地连接和接收来自iOS设备的消息,但未能在不崩溃的情况下读取消息。处理Swift中包含数组的结构指针
struct PTExampleTextFrame {
let length: UInt32
let utf8text: [UInt8]
}
func ioFrameChannel(channel: PTChannel?, didReceiveFrameOfType type: UInt32, tag: UInt32, payload: PTData?) {
if (type == PTExampleFrameTypeDeviceInfo) {
let deviceInfo: NSDictionary? = NSDictionary(contentsOfDispatchData: payload!.dispatchData)
self.presentMessage(NSString(format: "Connected to %@", deviceInfo!.description), isStatus:true)
} else if (type == PTExampleFrameTypeTextMessage) {
let textFramePointer = UnsafeMutablePointer<PTExampleTextFrame>(payload!.data)
let textFrameOptional: PTExampleTextFrame? = textFramePointer.memory
let textFrame: PTExampleTextFrame
if textFrameOptional != nil {
textFrame = textFrameOptional!
println(ntohl(textFrame.length))
println(textFrame.utf8text)
} else {
println("Recieved bad packet")
}
} else if (type == PTExampleFrameTypePong) {
self.pongWithTag(tag, error:nil)
}
}
结构和下面的块是我遇到的唯一问题。
let textFramePointer = UnsafeMutablePointer<PTExampleTextFrame>(payload!.data)
let textFrameOptional: PTExampleTextFrame? = textFramePointer.memory
let textFrame: PTExampleTextFrame
if textFrameOptional != nil {
textFrame = textFrameOptional!
println(ntohl(textFrame.length))
println(textFrame.utf8text)
} else {
println("Recieved bad packet")
}
当我的应用程序接收到一个消息时,ioFrameChannel功能调用成功,并打印该消息的适当的长度与
Thread 1: EXC_BAD_ACCESS (code=1, address=0x10)
崩溃时打印textFrame.utf8text行运行之前发送。
用一个不包含数组的结构替换成功,可按预期方式成功打印该消息的第一个字符的UTF-8表示形式。
struct PTExampleTextFrame {
let length: UInt32
let utf8text: UInt8
}
写在示例项目下面
//PTExampleProtocol.h
typedef struct _PTExampleTextFrame {
uint32_t length;
uint8_t utf8text[0];
} PTExampleTextFrame;
//PTAppDelegate.m
- (void)ioFrameChannel:(PTChannel*)channel didReceiveFrameOfType:(uint32_t)type tag:(uint32_t)tag payload:(PTData*)payload {
//NSLog(@"received %@, %u, %u, %@", channel, type, tag, payload);
if (type == PTExampleFrameTypeDeviceInfo) {
NSDictionary *deviceInfo = [NSDictionary dictionaryWithContentsOfDispatchData:payload.dispatchData];
[self presentMessage:[NSString stringWithFormat:@"Connected to %@", deviceInfo.description] isStatus:YES];
} else if (type == PTExampleFrameTypeTextMessage) {
PTExampleTextFrame *textFrame = (PTExampleTextFrame*)payload.data;
textFrame->length = ntohl(textFrame->length);
NSString *message = [[NSString alloc] initWithBytes:textFrame->utf8text length:textFrame->length encoding:NSUTF8StringEncoding];
[self presentMessage:[NSString stringWithFormat:@"[%@]: %@", channel.userInfo, message] isStatus:NO];
} else if (type == PTExampleFrameTypePong) {
[self pongWithTag:tag error:nil];
}
}
我想到撞车有事情做与阵列停止时,斯威夫特不知道目标C以上的作品。我怎么能在没有我的应用程序崩溃的情况下阅读Swift中的整个消息?
有机会看到你的代码? –
您必须将结构更改为与协议中的结构不相同,因此如果打算将其发送到其他地方,则必须转换为其他内存格式。你沿着这个线做一些事情来获得字节数组。 'UnsafeBufferPointer(baseAddress:payload.data + sizeof(UInt32),count:Int(UnsafePointer (payload.data).pointee))'你可能想清理一下或者把它分成多行或者其他内容。我不完全确定这是有效的Swift,因为我现在没有Xcode的副本,但希望你能得到它的要点。 –
谢谢@ deaton.dg。 –