如何使用线程在迅速?
dispatchOnMainThread:^{
NSLog(@"Block Executed On %s", dispatch_queue_get_label(dispatch_get_current_queue()));
}];
如何使用线程在迅速?
dispatchOnMainThread:^{
NSLog(@"Block Executed On %s", dispatch_queue_get_label(dispatch_get_current_queue()));
}];
当前回答
斯威夫特5
为了简化,创建一个“DispatchQueue+Extensions.swift”文件,内容如下:
import Foundation
typealias Dispatch = DispatchQueue
extension Dispatch {
static func background(_ task: @escaping () -> ()) {
Dispatch.global(qos: .background).async {
task()
}
}
static func main(_ task: @escaping () -> ()) {
Dispatch.main.async {
task()
}
}
}
用法:
Dispatch.background {
// do stuff
Dispatch.main {
// update UI
}
}
其他回答
你必须将你想要在后台运行的更改与你想要在UI上运行的更新分开:
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)) {
// do your task
dispatch_async(dispatch_get_main_queue()) {
// update some UI
}
}
快4.倍
把这些放到文件中:
func background(work: @escaping () -> ()) {
DispatchQueue.global(qos: .userInitiated).async {
work()
}
}
func main(work: @escaping () -> ()) {
DispatchQueue.main.async {
work()
}
}
然后在需要的地方调用它:
background {
//background job
main {
//update UI (or what you need to do in main thread)
}
}
斯威夫特5
为了简化,创建一个“DispatchQueue+Extensions.swift”文件,内容如下:
import Foundation
typealias Dispatch = DispatchQueue
extension Dispatch {
static func background(_ task: @escaping () -> ()) {
Dispatch.global(qos: .background).async {
task()
}
}
static func main(_ task: @escaping () -> ()) {
Dispatch.main.async {
task()
}
}
}
用法:
Dispatch.background {
// do stuff
Dispatch.main {
// update UI
}
}
Dan Beaulieu在swift5中给出了答案(从swift 3.0.1开始也可以工作)。
斯威夫特5.0.1
extension DispatchQueue {
static func background(delay: Double = 0.0, background: (()->Void)? = nil, completion: (() -> Void)? = nil) {
DispatchQueue.global(qos: .background).async {
background?()
if let completion = completion {
DispatchQueue.main.asyncAfter(deadline: .now() + delay, execute: {
completion()
})
}
}
}
}
使用
DispatchQueue.background(delay: 3.0, background: {
// do something in background
}, completion: {
// when background job finishes, wait 3 seconds and do something in main thread
})
DispatchQueue.background(background: {
// do something in background
}, completion:{
// when background job finished, do something in main thread
})
DispatchQueue.background(delay: 3.0, completion:{
// do something in main thread after 3 seconds
})
来自Jameson Quave的教程
斯威夫特2
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), {
//All stuff here
})