保存对象的数组属性的plist [英] Save array of objects with properties to plist

问题描述

我有一个包含不同的对象，如字符串，UIImage的，等一个可变数组
它们的排序是这样的：

I have a Mutable Array containing different objects such as strings, UIImage , etc. They are sorted like this:

例如：

BugData *bug1 = [[BugData alloc]initWithTitle:@"Spider" rank:@"123" thumbImage:[UIImage imageNamed:@"1.jpeg"]];
...
...
NSMutableArray *bugs = [NSMutableArray arrayWithObjects:bug1,bug2,bug3,bug4, nil];

所以基本上它是具有不同属性的对象的数组。

So basically it's an array with objects with different properties.

我想一个字符串保存到下一个code文件，它的工作很好，但是当我尝试保存的对象数组，我得到一个空的plist文件。

I Tried to save a single string to a file with the next code and it's working fine but when I try to save the array with the objects, i get an empty plist file.

NSString *docsDir = [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"];
NSString * path = [docsDir stringByAppendingPathComponent:@"data.plist"];
NSLog(@"%@",bugs); //Making sure the array is full
[bugs writeToFile:path atomically:YES];

我在做什么错了？

What am I doing wrong?

推荐答案

当你写一个字符串或任何原始数据的plist可以直接保存。但是，当您尝试保存一个对象，你需要使用NSCoding。

When you write a string or any primitive data to plist it can be saved directly. But when you try to save an object, you need to use NSCoding.

您必须实现两个方法连接codeWith codeR：来写 initWith codeR：来读它放回你的BugData类。

You have to implement two methods encodeWithCoder: to write and initWithCoder: to read it back in your BugData Class.

编辑：

事情是这样的：
更改浮点数到整数或字符串数​​组或者按照您的要求，并给予合适的钥匙给他们。

Something like this : Change Float to Integer or String or Array as per your requirement and give a suitable key to them.

- (void)encodeWithCoder:(NSCoder *)coder {
    [coder encodeObject:_title forKey:@"title"];
    [coder encodeFloat:_rating forKey:@"rating"];
    NSData *image = UIImagePNGRepresentation(_thumbImage);
    [coder encodeObject:(image) forKey:@"thumbImage"];
}


- (id)initWithCoder:(NSCoder *)coder {
    _title = [coder decodeObjectForKey:@"title"];
    _rating = [coder decodeFloatForKey:@"rating"];
    NSData *image = [coder decodeObjectForKey:@"thumbImage"];
    _thumbImage = [UIImage imageWithData:image];
    return self;
}

会帮助你。

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