Question

我需要使用JSON创建动态表单。我已经解析了JSON，但我不知道如何动态创建表单。我正在获取json数据，其中有一些控件，如复选框，文本字段和现在我想要根据问题创建的问题。与我们如何使用Google表单创建一样。请查看以下链接https://docs.google.com/forms/d/1lPn1aSvJsiDbJchsJjwsC93tWizXhj1qWkFPygt3oU4/viewform 请提供一些代码或教程。

Answer 1

我的想法是，步骤

1）创建模型类示例

     class UIControl
     {
          NSString *strControlName;
          NSString *strControlType;
          NSString *strControlValue;
          Bool  isSelected;
     }

2）解析json并创建模型类的对象

3）将模型类对象添加到arrOfControls

中

4）要么去表视图，要么只使用循环来遍历整个arrOfControls

5）以防万一，表视图检查cellForRowAtIndexPath控件类型。

6）为JSON数据可能带来的每个可能字段创建自定义单元格。

7）根据控件的类型，在删除函数（cellForRowAtIndexPath）中返回自定义单元格。例如： -

         if([[arrOfControls objectAtIndexPath:indexPath.row] strType] isEqualToString:@"TextField"]])
          {
                 //create object of customcell for textfield and return cell
           }
          else if([[arrOfControls objectAtIndexPath:indexPath.row] strType] isEqualToString:@"CheckBox"]])
          {
                 //create object of customcell for checkbox and return cell
          }
          else
          {
                //control type if not match any of the above
          }

这是粗略的想法而非实际代码。对于cellForRowAtIndexPath

，我的项目中的代码很少

       if(indexPath.section==0)
    {
        FormField *currControl=[fieldArray objectAtIndex:indexPath.row];
        if(([currControl.strFieldType caseInsensitiveCompare:@"TextLabel"]==NSOrderedSame )|| [currControl.strFieldType caseInsensitiveCompare:@"Text"]==NSOrderedSame)
        {
            TextFieldWithLabelTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"CellTextFieldWithLabel"];
            cell.txtTextField.delegate=self;
            [cell.txtTextField setTag:indexPath.row];
            if([currControl strFieldValue]==nil)
            {
                cell.txtTextField.text = @"";
                [cell.txtTextField setPlaceholder:[currControl strPlaceHolder]];
            }
            else
            {
                //if save value exists
                cell.txtTextField.text=@"";
                cell.txtTextField.text=[currControl strFieldValue];
            }
            cell.lblTextFieldIdenti.text=[[fieldArray objectAtIndex:indexPath.row] strFieldName];
            if([currControl.strFieldType caseInsensitiveCompare:@"Text"]==NSOrderedSame)
            {
                cell.lblTextFieldIdenti.text=@"";
            }
            [cell setSelectionStyle:UITableViewCellSelectionStyleNone];
            return cell;
        }
        else if(([currControl.strFieldType caseInsensitiveCompare:@"TextView"]==NSOrderedSame)||([currControl.strFieldType caseInsensitiveCompare:@"TextViewWithCam"]==NSOrderedSame))
        {
            TableViewTextAreaCell *cell = [tableView dequeueReusableCellWithIdentifier:@"TableViewTextAreaCell"];
            cell.txtView.delegate=self;
            cell.txtView.text=@"";
            if([currControl strFieldValue]!=nil)
            {
                //if save value exists
                cell.txtView.text=@"";
                cell.txtView.text=[currControl strFieldValue];
            }
            cell.fieldLabel.text=[[fieldArray objectAtIndex:indexPath.row] strFieldName];
            NSMutableArray *barItems = [[NSMutableArray alloc] init];
            UIToolbar* keyboardDoneButtonView = [[UIToolbar alloc] init];
            keyboardDoneButtonView.barStyle = UIBarStyleDefault;
            keyboardDoneButtonView.translucent = NO;
            keyboardDoneButtonView.barTintColor=[UIColor colorWithHue:0.6 saturation:0.33 brightness:0.69 alpha:0];
            [keyboardDoneButtonView sizeToFit];
            UIBarButtonItem *leftFlexSpace = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:self action:nil];
            [barItems addObject:leftFlexSpace];
            UIBarButtonItem *btnDone = [[UIBarButtonItem alloc] initWithTitle:NSLocalizedString(@"BTN_DONE", nil) style:UIBarButtonItemStyleBordered target:self action:@selector(pickerDoneClicked:)];

            [barItems addObject:btnDone];
            [keyboardDoneButtonView setItems:barItems animated:YES];
            [cell.txtView setInputAccessoryView:keyboardDoneButtonView];

            [cell configureCell:currControl.strFieldName];
            cell.fieldLabel.textColor=[UIColor darkTextColor];
            cell.txtView.backgroundColor =[UIColor colorWithHexString:@"#f3f1f2"];
            cell.fieldLabel.font=[UIFont systemFontOfSize:12];
            cell.selectionStyle=UITableViewCellSelectionStyleNone;
            [cell setSelectionStyle:UITableViewCellSelectionStyleNone];
            [cell.imgViewCam setHidden:TRUE];
            if([currControl.strFieldType caseInsensitiveCompare:@"TextViewWithCam"]==NSOrderedSame)
            {
                UITapGestureRecognizer *singleTap =  [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(CameraClicked:)];
                [singleTap setNumberOfTapsRequired:1];
                [cell.imgViewCam addGestureRecognizer:singleTap];
                [cell.imgViewCam setHidden:FALSE];

            }
            return cell;
        }
        else if([currControl.strFieldType caseInsensitiveCompare:@"DropDown"]==NSOrderedSame)
        {
            //if dropdwon box
            DropDownTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"CellDropDown"];
            cell.lblDropDownidentifier.text=[currControl strFieldName];
            [cell.btnDropDown setTag:indexPath.row];
            [cell.btnDropDown addTarget:self action:@selector(ShowOptions:) forControlEvents:UIControlEventTouchUpInside];
            [cell.btnDropDown setTitle:@"" forState:UIControlStateNormal];


            if([currControl strFieldValue]!=nil)
            {
                [cell.btnDropDown setTitle:[currControl strFieldValue] forState:UIControlStateNormal];
            }
            [cell setSelectionStyle:UITableViewCellSelectionStyleNone];
            if([[currControl strFieldName] caseInsensitiveCompare:@"Time Of Delivery:"]==NSOrderedSame)
            {
                cell.imgDropDown.image=[UIImage imageNamed:@"stopwatch.png"];
            }
            else if([[currControl strFieldName] caseInsensitiveCompare:@"Date Of Delivery:"]==NSOrderedSame)
            {
                cell.imgDropDown.image=[UIImage imageNamed:@"calendar.png"];
            }
            else
            {
                cell.imgDropDown.image=[UIImage imageNamed:@"dropdown.jpeg"];
            }

            return cell;

        }

Answer 2

这是我发现非常有趣并快速搜索的内容。根据您的JSON在其中的内容，我可以看到实现此目的的两种方法。

1。）如果你的JSON是这样的：

{＆＃34;输入＆＃34;：＆＃34; TextField＆＃34;，＆＃34;属性＆＃34; ：{ ＆＃34; Property1＆＃34;：＆＃34;值1＆＃34 ;, ＆＃34; Property2＆＃34;：＆＃34;值2＆＃34;} }

等

您必须拥有条件代码，具体取决于类型;

UIControl *newControl

if([[parsedJson valueForKey:@"Type"] isEqualTo:"TextField"])
{
   newControl = [UITextField alloc]init];
   for(NSDictionary *dict in [parsedJson valueForKey:"Properties")
   {
     [newControl setValue:[dict value] forKey:[dict Key]];
   }
}

另一方面，如果您的JSON使用类型的UIKit名称，例如：

{＆＃34;类型＆＃34;：＆＃34;的UITextField＆＃34;＆＃34;属性＆＃34; {＆＃34; Property1＆＃34;：＆＃34;值1＆＃34 ;, ＆＃34; Property2＆＃34;：2}}

等

你可以做一些反思：

id *control = [[NSClassFromString([parsedJson valueForKey:"Type"]) alloc] init];

       for(NSDictionary *dict in [parsedJson valueForKey:"Properties")
       {
         [newControl setValue:[dict value] forKey:[dict Key]];
       }

但是，如果系统无法创建类或者为不存在的属性设置值，则需要进行大量错误处理/ try {} catch {}。

JSON中声明的属性也需要引用类的属性。

用于此答案的一些参考文献：

how to instantiate an object of class from string in Objective-C? - StackOverflow Convert a string (“MyExampleClass”) into a class name (MyExampleClass) - StackOverflow

在iOS中使用JSON创建动态表单UI

2 个答案: