UI_10 表视图的编辑、UITableViewController

读取plist文件并将其内容显示到表视图上。并添加编辑（增加，删除）、移动cell的操作。

plist文件内容如下：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "
http://www.apple.com/DTDs/PropertyList-1.0.dtd
">
<plist version="1.0">
<dict>
  <key>北京</key>
        <array>
           <dict>
                     <key>area</key>
                      <string>100万</string>
                <key>name</key>
                      <string>海淀区</string>
         </dict>
            <dict>
            <key>area</key>
            <string>101万</string>
                   <key>name</key>
                      <string>朝阳区</string>
         </dict>
     </array>
   <key>新疆</key>
        <array>
           <dict>
            <key>area</key>
            <string>112万</string>
                   <key>name</key>
                      <string>乌鲁木齐</string>
        </dict>
            <dict>
            <key>area</key>
            <string>113万</string>
                   <key>name</key>
                      <string>哈密</string>
          </dict>
            <dict>
            <key>area</key>
            <string>114万</string>
                   <key>name</key>
                      <string>吐鲁番</string>
         </dict>
     </array>
</dict>
</plist>

结构图如下：

编辑的步骤如下：

• 1、进入可编辑状态
• 2、设置指定分区(section)中的行(row)是否可以被编辑
• 3、设置指定分区（section）中的行（row）是什么类型的编辑样式
• 4、编辑完成（一定要先操作数据，后操作UI）

//1、进入可编辑状态
- (void)setEditing:(BOOL)editing animated:(BOOL)animated
{
    [super setEditing:editing animated:animated];
   
    [_tableView setEditing:editing animated:animated];
   
}

//2、设置指定分区(section)中的行(row)是否可以被编辑
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (!indexPath.section&&!indexPath.row) {
        return NO;
    }
    return YES;
}

//3、设置指定分区（section）中的行（row）是什么类型的编辑样式
- (UITableViewCellEditingStyle)tableView:(UITableView *)tableView editingStyleForRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (indexPath.section==1) {
        return UITableViewCellEditingStyleInsert;
    }
    return UITableViewCellEditingStyleDelete;
}

//4、编辑完成（一定要先操作数据，后操作UI）
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
    switch (editingStyle) {
        case UITableViewCellEditingStyleDelete:
            NSLog(@"Delete");
            //1.先删除数据
            NSString *key=_keysArray[indexPath.section];
            NSMutableArray *array = _allCityDic[key];
            [array removeObjectAtIndex:indexPath.row];
           
            //2.操作UI
            [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationLeft];
           
            if (!array.count) {
                //1.先操作数据
                [_keysArray removeObject:key];
                [_allCityDic removeObjectForKey:key];
                //2.再操作UI
                [tableView deleteSections:[NSIndexSet indexSetWithIndex:indexPath.section] withRowAnimation:UITableViewRowAnimationBottom];
            }
           
           
            break;
        case UITableViewCellEditingStyleNone:
            NSLog(@"None");
            break;
        case UITableViewCellEditingStyleInsert:
            NSLog(@"Insert");
           
            City *aCity = [[City alloc] init];
           
            aCity.name = @"丰台区";
            aCity.area = @"30万";
           
            //1.数据
            NSString *key1 = _keysArray[indexPath.section];
            NSMutableArray *cityArray = _allCityDic[key1];
            [cityArray insertObject:aCity atIndex:indexPath.row];
           
            //2.UI
            [tableView insertRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationNone];
           
            break;
        default:
            break;
    }

}

最后，不要忘了添加编辑按钮

self.navigationItem.rightBarButtonItem = self.editButtonItem;

步骤：

• 1.让tableView处于可编辑状态（同上）
• 2.设置指定的分区section中的行row是否可以被移动
• 3.实现移动
• 4.限制跨区移动

//1.让tableView处于可编辑状态（同上）

//2.设置指定的分区section中的行row是否可以被移动
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
    return YES;
}
//3.实现移动
//方法:保存－删除－插入
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)sourceIndexPath toIndexPath:(NSIndexPath *)destinationIndexPath
{
    if (sourceIndexPath.row!=destinationIndexPath.row) {
        NSString *key = _keysArray[sourceIndexPath.section];
        NSMutableArray *citiesArray = _allCityDic[key];
        //获取数组中要被移动的元素
        City *aCity = citiesArray[sourceIndexPath.row];
        //    //保存
        //    [aCity retain];
        //    //删除(必须retain)
        //    [citiesArray removeObjectAtIndex:sourceIndexPath.row];
        //    //移动
        //    [citiesArray insertObject:aCity atIndex:destinationIndexPath.row];
        //    [aCity release];
       
        [citiesArray insertObject:aCity atIndex:destinationIndexPath.row];
        [citiesArray removeObjectAtIndex:sourceIndexPath.row+1];
    }
   
}

//4.限制跨区移动
-(NSIndexPath *)tableView:(UITableView *)tableView targetIndexPathForMoveFromRowAtIndexPath:(NSIndexPath *)sourceIndexPath toProposedIndexPath:(NSIndexPath *)proposedDestinationIndexPath
{
    //如果目的地与出发地位置在同一区
    if (sourceIndexPath.section == proposedDestinationIndexPath.section) {
        return proposedDestinationIndexPath;
    } else {
        return sourceIndexPath;
    }

}

注意：

• UITableViewController继承?UIViewController，?带?个tableView
• self.view不是UIView?是UITableView
• datasource和delegate默认都是self(UITableViewController)
• 开发中只需要建?UITableViewController?类