List 中的可重用性支持 - SwiftUI

如何解决List 中的可重用性支持 - SwiftUI

我目前正在开发一个使用 SwiftUI 的项目。我试图使用 List 显示一个包含 10 个项目的列表。

问题：List 是否像 UITableview 一样支持可重用性？

我浏览了多个帖子，所有帖子都说 List 支持可重用性。 Does the List in SwiftUI reuse cells similar to UITableView?

但该项目的内存映射说明了其他内容。 List 中的所有视图都是一次性创建的，不会重复使用。

编辑：

这是我如何创建 List

List {
    Section(header: TableHeader()) {
        ForEach(0..<10) {_ in
            TableRow()
        }
    }
}

TableHeader 和 TableRow 是创建的自定义视图。

有人可以澄清一下吗？

解决方法

List 实际上为可重用标识符提供了与 UITableView 相同的技术。你的代码使它像一个滚动视图。 正确的做法是提供项目作为迭代数据。

totalWorkingHours() {
    print("working hours");
    var totalWorkingMin;
    var totalWorkingSec;  
    var totalWorkingHour;
    var timeInHoursSplit;
    var timeOutHoursSplit;
    var timeInHours0;
    var timeOutHours0;
    List timeInHours;
    List timeOutHours;
    var inHour;
    var outHour;
    var inMin;
    var outMin;
    var inSec;
    var outSec;
    var flagMin = false;
    var flagSec = false;

    var defaultIn = " 00:00:00 PM";
    var defaultOut = " 00:00:00 PM";

    var data = {};

    //here i am getting the time in and time out values and using api if in case user logout,and spliting it to get the hours,min and sec
    if(workinghours=="0" && getapitimeout==""){
      print("11");
      timeInHoursSplit = defaultIn.split(' '); //18:35:00 PM
      timeOutHoursSplit = defaultOut.split(' ');
    }
    else if (workinghours == "0" && getTimeInStatus == true) {
      print("12");
      timeInHoursSplit = gettimeinvalue.split(' '); //18:35:00 PM
      timeOutHoursSplit = getapitimeout.split(' ');
    }
    //if logged in,did timein and timeout at once.
    else if(gettimeinworkinghours=="0" && getapitimeout!=""){
      print("13");
      print(getapitimein);
      print(getapitimeout);
      timeInHoursSplit = getapitimein.split(' ');
      timeOutHoursSplit = getapitimeout.split(' ');
    } 
    //if not time in and time out yet
    else {
      print("14");
      print(getapitimeout);
      timeInHoursSplit = defaultIn.split(' ');
      timeOutHoursSplit = defaultOut.split(' ');
    }
    print("1");
    print(timeInHoursSplit); //[18:35:00,PM]

    timeInHours0 = timeInHoursSplit[1]; //18:35:00
    print("2");
    print(timeInHours0);
    timeOutHours0 = timeOutHoursSplit[1];

    timeInHours = timeInHours0.split(':'); //[18,35,00]
    print(timeInHours);

    timeOutHours = timeOutHours0.split(':');

    inHour = timeInHours[0];
    outHour = timeOutHours[0];

    inMin = timeInHours[1];
    outMin = timeOutHours[1];

    inSec=timeInHours[2];
    outSec=timeOutHours[2];

   // here i am calculating the hours
    if (int.parse(inHour) > int.parse(outHour)) {
      totalWorkingHour = int.parse(inHour) - int.parse(outHour);
      print(totalWorkingHours);
    } else {
      totalWorkingHour = int.parse(outHour) - int.parse(outHour);
      print(totalWorkingHours);
    }

// here i am calculating the min
    if (inMin != outMin) {
      if (int.parse(outMin) > int.parse(inMin)) {
        totalWorkingMin = int.parse(outMin) - int.parse(inMin);
        flagMin = true;
      } else if (int.parse(inMin) > int.parse(outMin)) {
        totalWorkingMin = int.parse(inMin) - int.parse(outMin);
        flagMin = true;
      }
    } else if (inMin == outMin) {
      totalWorkingMin = int.parse(outMin) - int.parse(inMin);
      flagMin = true;
    }

// here i am calculating the sec
    if (inSec != outSec) {
      if (int.parse(outSec) > int.parse(inSec)) {
        totalWorkingSec = int.parse(outSec) - int.parse(inSec);
        flagSec = true;
      } else if (int.parse(inSec) > int.parse(outSec)) {
        totalWorkingSec = int.parse(inSec) - int.parse(outSec);
        flagSec = true;
      }
    } else if (inSec == outSec) {
      totalWorkingSec = int.parse(outSec) - int.parse(inSec);
      flagSec = true;
    }


    //// here i am getting the totalworkinghours by concatenating the hours,min and sec
    if (flagMin == true && flagSec==true) {
      print("1 output");
      totalTime = totalWorkingHour.toString() +":" +totalWorkingMin.toString() +":"+totalWorkingSec.toString();
      print(totalTime);        
      return totalTime;  
    }

    //cond 2
    else if (flagMin == false && flagSec==false){
      print("2 output");
      totalTime = totalWorkingHour.toString() +":" +inMin.toString() + ":" +inSec.toString();    
      return totalTime;    
    } 

    //cond 3
    else if (flagMin == false && flagSec == true) {
      print("3 output");
      totalTime = totalWorkingHour.toString() +":" +inMin.toString() ;
     
      return totalTime;


    } 

    //cond 4
    else if (flagMin == true && flagSec == false) {
      print("4 output");
      totalTime = totalWorkingHour.toString() +":" +totalWorkingMin.toString() +":" +inSec.toString();
     
      return totalTime;

    }
  }

struct Item: Identifiable {
    var id = UUID().uuidString
    var name: String
}

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