Question

我正在使用切换控件，每当我从页面导航或重新启动应用程序时，其值设置为默认“关闭”。如何过来，如果按下它应该保持开启或如果按下它应该保持关闭，直到我们手动更改？

这是我的代码，我正在为scrollview分配和设置ffram

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell new";
     listData =[self.tableContents objectForKey:[self.sortedgroups objectAtIndex:[indexPath section]]];


    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier]autorelease];

    }
    NSUInteger row = [indexPath row];
    cell.textLabel.text = [listData objectAtIndex:row];


    if(indexPath.section==0)
    {  
        switch (indexPath.row) 
        {
            case 0:
            {
                switcher = [[[UISwitch alloc] initWithFrame:CGRectZero] autorelease];
                [switcher addTarget:self action:@selector(switchAction:)
                   forControlEvents:UIControlEventValueChanged];
                cell.accessoryView = switcher;
                switcher.tag = indexPath.row;


                //cell.textLabel.text=@"switcher";

            } 
                break;
            case 1: 
            {


                slide = [[[UISlider alloc] initWithFrame:CGRectMake(0,0, 150, 15)] autorelease];
                [slide addTarget:self action:@selector(slideact:)
                forControlEvents:UIControlEventValueChanged];
                cell.accessoryView = slide;
                // slide.tag = indexPath.row;                
            } 
                break;

}
}
}

这是我的切换操作方法：

- (void)switchAction:(UISwitch*)sender
{
    NSLog(@"switchAction: sender = %d, isOn %d", [sender tag], [sender isOn]);

    if(sender.on)
    {

[[NSUserDefaults standardUserDefaults]setObject:@"on" forKey:@"switcher"];
        [[NSUserDefaults standardUserDefaults]synchronize];

    }
    else
    {
[[NSUserDefaults standardUserDefaults]setObject:@"off" forKey:@"switcher"];
        [[NSUserDefaults standardUserDefaults]synchronize];

    }
}

-(void)viewWillAppear:(BOOL)animated
{
if ([[[NSUserDefaults standardUserDefaults]valueForKey:@"switcher"]isEqualToString:@"on"])
 {

switcher.on=YES;

    }
else
{
switcher.on=NO;
}

}

Answer 1

那么你需要保存开关的状态。为此，您甚至可以使用数据库或NSUserDefaults。使用NSUserDefaults会好得多。

- (void)switchAction:(UISwitch*)sender
{
    DEBUGLOG(NSLog(@"switchAction: sender = %d, isOn %d", [sender tag], [sender isOn]));

    if(sender.on)
    {

[[NSUserDefaults standardUserDefaults]setObject:@"on" forKey:@"switch"];
        [[NSUserDefaults standardUserDefaults]synchronize];

    }
    else
    {
[[NSUserDefaults standardUserDefaults]setObject:@"off" forKey:@"switch"];
        [[NSUserDefaults standardUserDefaults]synchronize];

    }
}

然后在viewwillAppear方法中执行以下操作

-(void)viewWillAppear:(BOOL)animated
{
if ([[[NSUserDefaults standardUserDefaults]valueForKey:@"switch"]isEqualToString:@"on"]) {

switch.Ison=YES;

    }
else
{
switch.Ison=NO;
}
}

Answer 2

您应该有一个值来保存开关控制状态可能会在用户首选项上。导航到此视图时，应检查此值。

Boolean status=YES;   // You should read this value from User Preference for example it represent the last status set to the switch control.
[switchView setOn:status animated:NO];

有关读取和写入用户首选项的信息，请参阅以下问题： iphone-reading-and-saving-preferences

Answer 3

您只需使用此方法即可开启和关闭此开关

- (void)switchAction:(UISwitch*)sender
{
    DEBUGLOG(NSLog(@"switchAction: sender = %d, isOn %d", [sender tag], [sender isOn]));

    if(sender.on)
    {

    }
    else
    {

    }
}

如果您想将其设置为默认值，那么您只需要在应用程序中将其设置为在viewwillappear中的实现文件中或在实现后的文件顶部

switch.on=YES;

如何在应用程序中保存切换状态

3 个答案: