Mac OSX 开发入门基础系列之NSTask

@IBAction func selectPath(_ sender: NSButton) {
        // 1. 创建打开文档面板对象
        let openPanel = NSOpenPanel()
        // 2. 设置确认按钮文字
        openPanel.prompt = "Select"
        // 3. 设置禁止选择文件
        openPanel.canChooseFiles = true
        // 4. 设置可以选择目录
        openPanel.canChooseDirectories = true
        // 5. 弹出面板框
        openPanel.beginSheetModal(for: self.view.window!) { (result) in
            // 6. 选择确认按钮
            if result == NSModalResponseOK {
                // 7. 获取选择的路径
                self.savePath.stringValue = (openPanel.directoryURL?.path)!
                // 8. 保存用户选择路径(为了获取访问权限)
                UserDefaults.standard.setValue(openPanel.url?.path, forKey: kSelectedFilePath)
                UserDefaults.standard.synchronize()
            }
            // 9. 恢复按钮状态
            sender.state = NSOffState
        }
    }

@IBAction func startPull(_ sender: NSButton) {
        guard  let executePath = UserDefaults.standard.value(forKey: kSelectedFilePath) as? String else {
            print("no selected path")
            return
        }
        guard repoPath.stringValue != "" else {return}
        if isLoadingRepo {return}   // 如果正在执行,则返回
        isLoadingRepo = true   // 设置正在执行标记
        task = Process()     // 创建NSTask对象
        // 设置task
        task?.launchPath = "/bin/bash"    // 执行路径(这里是需要执行命令的绝对路径)
        // 设置执行的具体命令
        task?.arguments = ["-c","cd \(executePath); git clone \(repoPath.stringValue)"]
        
        task?.terminationHandler = { proce in              // 执行结束的闭包(回调)
            self.isLoadingRepo = false    // 恢复执行标记
            print("finished")
            self.showFiles()   // 显示clone的仓库文件列表
        }
        captureStandardOutputAndRouteToTextView(task!)
        task?.launch()                // 开启执行
        task?.waitUntilExit()       // 阻塞直到执行完毕
    }
 // 显示目录文档列表
    fileprivate func showFiles() {
        guard  let executePath = UserDefaults.standard.value(forKey: kSelectedFilePath) as? String else {
            print("no selected path")
            return
        }
       let listTask = Process()     // 创建NSTask对象
        // 设置task
        listTask.launchPath = "/bin/bash"    // 执行路径(这里是需要执行命令的绝对路径)
        // 设置执行的具体命令
       
        listTask.arguments = ["-c","cd \(executePath + "/" + (repoPath.stringValue as NSString).lastPathComponent); ls "]
    
        captureStandardOutputAndRouteToTextView(listTask)
        
        listTask.launch()                // 开启执行
        listTask.waitUntilExit()
        
    }

     extension ViewController{
      fileprivate func captureStandardOutputAndRouteToTextView(_ task:Process) {
     //1. 设置标准输出管道
     outputPipe = Pipe()
     task.standardOutput = outputPipe
     
     //2. 在后台线程等待数据和通知
     outputPipe.fileHandleForReading.waitForDataInBackgroundAndNotify()
     
     //3. 接受到通知消息
     NotificationCenter.default.addObserver(forName: NSNotification.Name.NSFileHandleDataAvailable, object: outputPipe.fileHandleForReading , queue: nil) { notification in
         
         //4. 获取管道数据 转为字符串
         let output = self.outputPipe.fileHandleForReading.availableData
         let outputString = String(data: output, encoding: String.Encoding.utf8) ?? ""
         if outputString != ""{
             //5. 在主线程处理UI
             DispatchQueue.main.async(execute: {
                 let previousOutput = self.showInfoTextView.string ?? ""
                 let nextOutput = previousOutput + "\n" + outputString
                 self.showInfoTextView.string = nextOutput
                 // 滚动到可视位置
                 let range = NSRange(location:nextOutput.characters.count,length:0)
                 self.showInfoTextView.scrollRangeToVisible(range)
             })
         }            
         //6. 继续等待新数据和通知
         self.outputPipe.fileHandleForReading.waitForDataInBackgroundAndNotify()
               }
            }
       }

func execCmd(cmd: String, arguments: [String]) -> String{
    let task = Process()     // 创建NSTask 实例
    task.launchPath = cmd        // 需要执行的命令
    task.arguments = arguments    // 命令参数
    let output = Pipe()                  // 创建输出实例
    task.standardOutput = output          // 设置输出
    task.launch()                                     // 执行命令
    task.waitUntilExit()                          // 等待退出
    let data = output.fileHandleForReading.readDataToEndOfFile()      // 获取执行结果数据
    return String(data: data, encoding: String.Encoding.utf8) ?? ""     // 返回结果
}