与iPhone DropBox API的简单同步

I am getting slightly frustrated with the DropBox API. It is supposed to be all simple and straight forward, but I have yet to come a across a simple and plain explanation of how to do a simple sync.

我对DropBox API感到有点沮丧。它应该是简单而直接的，但我还没有简单而简单地解释如何进行简单的同步。

I followed all the instruction you can find in the readme which comes withe DropBox API. To test the whole thing, I have created two buttons to download and upload a file from or to my DropBox. The files are found in my app documents folder.

我按照DropBox API自述文件中的所有说明进行了操作。为了测试整个事情，我创建了两个按钮来下载文件或从我的DropBox上传文件。这些文件位于我的应用文档文件夹中。

This works splendidly:

这非常有效：

    -(void) DBupload:(id)sender
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0]; // Get documents directory
    NSString *filePath = [documentsDirectory stringByAppendingPathComponent:@"MyExample.txt"];
    // NSError *error;
    [self.restClient uploadFile:@"MyExample.txt" toPath:@"/MyExamplePath" fromPath:filePath];
}

-(void) DBdownload:(id)sender
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); 
    NSString *documentsDirectory = [paths objectAtIndex:0]; // Get documents directory
    NSString *filePath = [documentsDirectory stringByAppendingPathComponent:@"MyExample.txt"];
    NSError *error;
    [self.restClient loadFile:@"/myExamplePath/MyExample.txt" intoPath:filePath];
}

However, I am now wondering how to achieve a simply sync. Right now, I can manually upload and download. But what I need in order to sync is to:

但是，我现在想知道如何实现简单的同步。现在，我可以手动上传和下载。但我需要同步的是：

find out if the MyExample.txt in my App's folder or in my DropBox folder is more recent
找出我的应用程序文件夹或我的DropBox文件夹中的MyExample.txt是否更新
if the txt in the App's folder is more recent: drop it into dropbox (overriding the old), i.e. call my DBupload method
如果应用程序文件夹中的txt更新：将其放入dropbox（覆盖旧文件夹），即调用我的DBupload方法
if the txt in the drop box is more recent: download it into the apps folder, i.e. call my DBdownload method
如果下拉框中的txt更新：将其下载到apps文件夹中，即调用我的DBdownload方法

Perhaps I am just too dumb, but does dropBox detail somewhere how to achieve this rather simple and straight forward task?

也许我只是太愚蠢，但在某处如何实现这个相当简单和直接的任务dropBox细节？

I know that there is this but it doesn't really give any code samples.

我知道有这个，但它并没有给出任何代码示例。

Thanks for any suggestions.

谢谢你的任何建议。

EDIT

编辑

OK, so I figured that my first step is to find out the last modified date of MyExample.txt which is found in the dropBox.

好的，所以我想我的第一步是找出在dropBox中找到的MyExample.txt的最后修改日期。

I wrote a wonderful method called DBsync in which I simply put this command:

我写了一个名为DBsync的奇妙方法，我只需输入以下命令：

 -(void) DBsync
{
    [self.restClient loadMetadata:@"/myExamplePath"];

}

This calls the following method which gets the metadata. This was a suggested answer to this post, and I commented it a bit out so as to make it plain what is happening (if there are more dumb people like myself:

这将调用以下获取元数据的方法。这是对这篇文章的一个建议的答案，我稍微评论了一下，以便说清楚发生了什么（如果有更多像我这样愚蠢的人：

 - (void)restClient:(DBRestClient*)client loadedMetadata:(DBMetadata*)metadata {

    NSLog(@"restClient:loadedMetadata function called");

    NSEnumerator *e= [metadata.contents objectEnumerator]; // indexes files in dropbox?
    DBMetadata *dbObject;   // loads metadate we need, e.g. lastModifiedDated
    int numberOfFiles = [metadata.contents count]; // counts files in DropBox - I guess we don't really need this
    NSLog(@"numberOfFiles %i", numberOfFiles); 

    while ((dbObject = [e nextObject])) { // this goes through every single file in the DropBox
        if (!dbObject.isDirectory) { // this determines whether we are talking about a file or a folder
            NSString *fileName = [dbObject.path lastPathComponent]; // this puts the name of the last component, e.g. in /MyExamplePath/MyExample.txt = MyExample.txt into fileName
            NSLog(@"File which is currently being checked: %@", fileName);

            if ([fileName isEqualToString:@"MyExample.txt"]) {  

                NSLog(@"Found it: %@", fileName);
                NSLog(@"Date last modified: %@", dbObject.lastModifiedDate); 

                /* to do: call dbupload if dbObject.lastModifiedDate > than your local file*/
            }
        }
    }
}

I will post the next step once I managed to do so...

一旦我设法这样做，我将发布下一步...

2 个解决方案

#1

I think what you are looking for is the loadmetadata method. Here is an untested example:

我认为你要找的是loadmetadata方法。这是一个未经测试的例子：

- (void)restClient:(DBRestClient*)client loadedMetadata:(DBMetadata*)metadata {
    NSEnumerator *e= [metadata.contents objectEnumerator];
    DBMetadata *dbObject;
    numberOfFiles = [metadata.contents count];
    while ((dbObject = [e nextObject])) {
    if (!dbObject.isDirectory) {
        NSString *fileName = [dbObject.path lastPathComponent];
        if (![fileName isEqualToString:@"MyExample.txt"]) {  
           /* call dbupload if dbObject.lastModifiedDate > than your local file*/
        }
    }
}

#2

You don't need an enumerator, just use the good old for... loop ;)

你不需要一个枚举器，只需使用旧的for ...循环;）

- (void)restClient:(DBRestClient *)client loadedMetadata:(DBMetadata *)metadata {
    for (DBMetadata * child in metadata.contents) {
        if (!child.isDirectory) {
            NSString *fileName = [dbObject.path lastPathComponent];
            if (![fileName isEqualToString:@"MyExample.txt"]) {  
                /* call dbupload if dbObject.lastModifiedDate > than your local file*/
            }
        }
    }
}

#1