Question

我看了几个例子，但在尝试保存文本字段输入并在重新启动应用程序时重新加载时，我无法弄清楚出了什么问题。我的.m文件中有类似的内容（.h文件只有<UITextViewDelegate>）;

@implementation C4WorkSpace{
    UITextView *textField;
    C4Button *okButton;
    C4Label *savedText;
}

-(void)setup {
    //add text field
    CGRect textViewFrame = CGRectMake(20.0f, 20, self.canvas.width-40, 124.0f);
    textField = [[UITextView alloc] initWithFrame:textViewFrame];
    textField.returnKeyType = UIReturnKeyDone;
    [textField becomeFirstResponder];
    textField.delegate = self;
    //textField.hidden=true;

    [self.view addSubview:textField];

    okButton=[C4Button buttonWithType:ROUNDEDRECT];
    [okButton setTitle:@"Save" forState:NORMAL];
    okButton.center=self.canvas.center;
    [self.canvas addUIElement:okButton];
    [okButton runMethod:@"saveDefault" target:self forEvent:TOUCHUPINSIDE];

    savedText=[C4Label labelWithText:@"default"];
    savedText.center=CGPointMake(self.canvas.center.x, self.canvas.center.y+40);
    [self.canvas addLabel:savedText];
}
-(void)saveDefault{
    NSUserDefaults *defaults=[NSUserDefaults standardUserDefaults];

    [defaults setObject:textField.text forKey:@"userName"];
    [defaults synchronize];
    C4Log(@"defaults: %@",defaults);
    C4Log(@"defaults: %@", [defaults objectForKey:@"userName"]);
    savedText.text=textField.text;
}
-(void)viewDidLoad{
    NSMutableString *text=[[NSUserDefaults standardUserDefaults] objectForKey:@"userName"];
    C4Log(@"loadedText:%s", text);
    textField.text=text;
    savedText.text=text;
}
@end

我不确定到底出了什么问题，但是当我重新启动应用程序时，loadedText始终是：“¯8*：å”。无论我保存了什么。

Answer 1

我发现最简单的解决方案是设置

<强> viewDidLoad中

text=[[NSUserDefaults standardUserDefaults] objectForKey:@"userName"];

并在设置

中

if (text!=nil) {
        textField.text=text;
    }

Answer 2

调用Setup方法的位置？我认为在viewDidLoad中你初始化，但是之前调用的setup方法。您不保存此信息，因此按钮在初始化之前无法识别或加载信息并设置文本。在设置方法加载信息

UItextView *k = [UItextView alloc] init];
k.text = [[NSUserDefaults standardUserDefaults] objectForKey:@"userName"];

并看看将会是什么。

更新：

那是错的;

[c4workspace loadInfoFromDefaults];
[c4workspace alloc]init];  (calls viedidload method with load info)

你需要

[c4workspace alloc]init]; 
[c4workspace loadInfoFromDefaults];

请在创建c4WorkSpace对象的位置发布代码。

更新2：

-(void)setup {

    //add text field
    CGRect textViewFrame = CGRectMake(20.0f, 20, self.canvas.width-40, 124.0f);
    textField = [[UITextView alloc] initWithFrame:textViewFrame];
    textField.returnKeyType = UIReturnKeyDone;
    [textField becomeFirstResponder];
    textField.delegate = self;
    //textField.hidden=true;

    [self.view addSubview:textField];

    okButton=[C4Button buttonWithType:ROUNDEDRECT];
    [okButton setTitle:@"Save" forState:NORMAL];
    okButton.center=self.canvas.center;
    [self.canvas addUIElement:okButton];
    [okButton runMethod:@"saveDefault" target:self forEvent:TOUCHUPINSIDE];

    savedText=[C4Label labelWithText:@"default"];
    savedText.center=CGPointMake(self.canvas.center.x, self.canvas.center.y+40);
    [self.canvas addLabel:savedText];
}

- (void) setTextView
{
    textField.text=[[NSUserDefaults standardUserDefaults] objectForKey:@"userName"];
    savedText.text=[[NSUserDefaults standardUserDefaults] objectForKey:@"userName"];
}

所以你称之为：

C4WorkSpace *c4 = [C4WorkSpace alloc] init];
[c4 setup]
[c4 setTextView];

保存用户默认值[iOS]

2 个答案: