blocks|key|4655134|text|在毕加索的最新版本中，有一种新的无效方法，没有任何变通方法，所以我认为前面提到的自定义PicassoTools类在这种情况下已经过时了|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4655135|Picasso.with(getActivity()).invalidate(file);|code-block|syntax|javascript|4655136|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

In the recent versions of Picasso, there is a new method for invalidate, without any workarounds, so I think that custom PicassoTools class mentioned earlier, is now obsolete in this case

<pre><code>Picasso.with(getActivity()).invalidate(file);
</code></pre>

blocks|key|148512|text|实际上，根据您自己的答案，有一种更简单的方法来完成这项工作，而不需要派生库。将此类添加到com.squareup.picasso包中。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|148513|package+com.squareup.picasso;

public+class+PicassoTools+{

++++public+static+void+clearCache+(Picasso+p)+{
++++++++p.cache.clear();
++++}
}|code-block|syntax|javascript|148514|因为缓存具有包可见性，所以这个util类可以为您清除缓存。你只需要把它叫做：|148515|PicassoTools.clearCache(Picasso.with(context));|148516|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Actually, based on your own answer, there is an easier way to do it without forking the library. Add this class to the com.squareup.picasso package.

<pre><code>package com.squareup.picasso;

public class PicassoTools {

 public static void clearCache (Picasso p) {
 p.cache.clear();
 }
}
</code></pre>

Because cache has package visibility, this util class can clear the cache for you. You just have to call it:

<pre><code>PicassoTools.clearCache(Picasso.with(context));
</code></pre>

blocks|key|4655172|text|通过标志指示内存策略中止内存缓存和磁盘缓存检查:+emoryPolicy.NO_CACHE和NetworkPolicy.NO_CACHE，如下代码片段所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4655173|+++mPicasso.with(mContext)
++++++++++++.load(url)
++++++++++++.memoryPolicy(MemoryPolicy.NO_CACHE+)
++++++++++++.networkPolicy(NetworkPolicy.NO_CACHE)
++++++++++++.resize(512,+512)
++++++++++++.error(R.drawable.login)
++++++++++++.noFade()
++++++++++++.into(imageView);|code-block|syntax|javascript|4655174|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Abort memory cache and disk cache check by indicate memory policy by flag: emoryPolicy.NO_CACHE and NetworkPolicy.NO_CACHE as below code snippet:

<pre><code> mPicasso.with(mContext)
 .load(url)
 .memoryPolicy(MemoryPolicy.NO_CACHE )
 .networkPolicy(NetworkPolicy.NO_CACHE)
 .resize(512, 512)
 .error(R.drawable.login)
 .noFade()
 .into(imageView);
</code></pre>

blocks|key|148485|text|尝试使用：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|148486|Picasso.with(ctx).load(new+File("/path/to/image")).skipMemoryCache().into(imageView)|code-block|syntax|javascript|148487|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Try to use:

<pre><code>Picasso.with(ctx).load(new File("/path/to/image")).skipMemoryCache().into(imageView)
</code></pre>

blocks|key|148534|text|另一种选择是删除缓存目录本身，例如在应用程序启动时：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|148535|deleteDirectoryTree(context.getCacheDir());|code-block|syntax|javascript|148536|其中：|148537|/**
+*+Deletes+a+directory+tree+recursively.
+*/
public+static+void+deleteDirectoryTree(File+fileOrDirectory)+{
++++if+(fileOrDirectory.isDirectory())+{
++++++++for+(File+child+:+fileOrDirectory.listFiles())+{
++++++++++++deleteDirectoryTree(child);
++++++++}
++++}

++++fileOrDirectory.delete();
}|148538|这将删除整个缓存目录，如果您想要模拟应用程序的首次使用，这是很好的。如果您只想删除毕加索缓存，请在路径中添加"+Picasso+-+cache“。|148539|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Another option is to delete the cache directory itself, for example on app startup:

<pre><code>deleteDirectoryTree(context.getCacheDir());
</code></pre>

where:

<pre><code>/**
 * Deletes a directory tree recursively.
 */
public static void deleteDirectoryTree(File fileOrDirectory) {
 if (fileOrDirectory.isDirectory()) {
 for (File child : fileOrDirectory.listFiles()) {
 deleteDirectoryTree(child);
 }
 }

 fileOrDirectory.delete();
}
</code></pre>

That deletes the whole cache directory, which is fine if you want to simulate first-use of your app. If you only want to delete the Picasso cache, add "picasso-cache" to the path.

blocks|key|148771|text|如果你想一次删除所有的缓存，你可以做的就是创建一个自定义的Picasso.LruCache，然后在它上面使用clear方法。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|148772|下面是一个示例：|148773|Picasso.Builder+builder+=+new+Picasso.Builder(this);
LruCache+picassoCache+=+new+LruCache(this);
builder.memoryCache(picassoCache);
Picasso.setSingletonInstance(builder.build());|code-block|syntax|javascript|148774|要清除缓存，请执行以下操作：|148775|picassoCache.clear();|148776|entityMap^0|T|G|1I|5|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|X|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|Y|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|Z|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|10|8|@]|D|@]|E|$K|L]]|$1|Q|3|-4|5|6|7|11|8|@]|D|@]|E|$]]]|R|$]]

What you can do if you want to delete all cache at once, is to create a custom <code>Picasso.LruCache</code>, and then use the <code>clear</code> method on it.

Here is a sample:

<pre><code>Picasso.Builder builder = new Picasso.Builder(this);
LruCache picassoCache = new LruCache(this);
builder.memoryCache(picassoCache);
Picasso.setSingletonInstance(builder.build());
</code></pre>

To clear the cache:

<pre><code>picassoCache.clear();
</code></pre>

blocks|key|148925|text|您可以通过设置自己的缓存来清除毕加索的图像缓存。这段代码是在毕加索2.5.0上测试的|type|unstyled|depth|inlineStyleRanges|entityRanges|data|148926|private+Picasso+picasso;
private+LruCache+picassoLruCache;

picassoLruCache+=+new+LruCache(context);

//+Set+cache
picasso+=+new+Picasso.Builder(context)+//
++++++++.memoryCache(picassoLruCache)+//
++++++++.build();

//+Clear+cache
picassoLruCache.clear();|code-block|syntax|javascript|148927|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can clear image cache of picasso by setting your own cache and clear that.
This code was tested on Picasso 2.5.0

<pre><code>private Picasso picasso;
private LruCache picassoLruCache;

picassoLruCache = new LruCache(context);

// Set cache
picasso = new Picasso.Builder(context) //
 .memoryCache(picassoLruCache) //
 .build();

// Clear cache
picassoLruCache.clear();
</code></pre>

blocks|key|148861|text|循环不是很好，但是这种方法解决了缓存和毕加索的问题。只有当你想要使特定URL的缓存无效时才使用这个方法，这个方法很慢，可能不是正确的方法，但对我来说是有效的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|148862|++++String+url+=+"http://www.blablabla.com/Raiders.jpg";
++++Picasso.with(this).invalidate(url);
++++Picasso.with(this)
++++++++++++.load(url)
++++++++++++.networkPolicy(
++++++++++++++++++++NetworkUtils.isConnected(this)+?
++++++++++++++++++++++++++++NetworkPolicy.NO_CACHE+:+NetworkPolicy.OFFLINE)
++++++++++++.resize(200,+200)
++++++++++++.centerCrop()
++++++++++++.placeholder(R.mipmap.ic_avatar)
++++++++++++.error(R.mipmap.ic_avatar)
++++++++++++.into(imageView);|code-block|syntax|javascript|148863|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Doesn't loop pretty, but this approach fixed my issue with cache and Picasso. Only use this when you want to invalidate the cache for a specific URL, this approach is slow and probably is not the correct way of doing but works for me.

<pre><code> String url = "http://www.blablabla.com/Raiders.jpg";
 Picasso.with(this).invalidate(url);
 Picasso.with(this)
 .load(url)
 .networkPolicy(
 NetworkUtils.isConnected(this) ?
 NetworkPolicy.NO_CACHE : NetworkPolicy.OFFLINE)
 .resize(200, 200)
 .centerCrop()
 .placeholder(R.mipmap.ic_avatar)
 .error(R.mipmap.ic_avatar)
 .into(imageView);
</code></pre>

blocks|key|4655540|text|在这里，被接受的答案中缺少一个非常重要的部分。我从这里找到了诀窍：http://blogs.candoerz.com/question/124660/android-image-cache-is-not-clearing-in-picasso.aspx|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|4655541|当你在显示原始图像时使用调整大小、居中裁剪等自定义选项时，仅仅调用下面这行代码并不会清除照片的缓存。|4655542|Picasso.with(getContext()).invalidate(file);|code-block|syntax|javascript|4655543|解决方案：|4655544|在显示图片时，使用stableKey()方法。|style|CODE|4655545|Picasso.with(getContext()).load(new+File(fileUri))
+++++++++++++++++++++++++.skipMemoryCache()
+++++++++++++++++++++++++.placeholder(R.drawable.placeholder)
+++++++++++++++++++++++++.stableKey(fileUri)
+++++++++++++++++++++++++.into(imageview);|4655546|然后，您可以稍后通过调用以下命令来清除此文件的缓存：|4655547|Picasso.with(getContext()).invalidate(fileUri);|4655548|希望这能有所帮助。|4655549|entityMap|0|LINK|mutability|MUTABLE|url|http://blogs.candoerz.com/question/124660/android-image-cache-is-not-clearing-in-picasso.aspx^0|X|2L|0|0|0|0|0|9|B|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|16|8|@]|9|@$A|17|B|18|1|19]]|C|$]]|$1|D|3|E|5|6|7|1A|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|1B|8|@]|9|@]|C|$I|J]]|$1|K|3|L|5|6|7|1C|8|@]|9|@]|C|$]]|$1|M|3|N|5|6|7|1D|8|@$A|1E|B|1F|O|P]]|9|@]|C|$]]|$1|Q|3|R|5|H|7|1G|8|@]|9|@]|C|$I|J]]|$1|S|3|T|5|6|7|1H|8|@]|9|@]|C|$]]|$1|U|3|V|5|H|7|1I|8|@]|9|@]|C|$I|J]]|$1|W|3|X|5|6|7|1J|8|@]|9|@]|C|$]]|$1|Y|3|-4|5|6|7|1K|8|@]|9|@]|C|$]]]|Z|$10|$5|11|12|13|C|$14|15]]]]

A very important part is missing from the accepted answer here. I found the trick from here: <a href="http://blogs.candoerz.com/question/124660/android-image-cache-is-not-clearing-in-picasso.aspx" rel="nofollow noreferrer">http://blogs.candoerz.com/question/124660/android-image-cache-is-not-clearing-in-picasso.aspx</a>

Just calling the following line, wouldn't clear the cache of a photo when you use custom options like resize, center crop etc when displaying the original image.

<pre><code>Picasso.with(getContext()).invalidate(file);
</code></pre>

The solution:

When displaying the image, use <code>stableKey()</code> method. 

<pre><code>Picasso.with(getContext()).load(new File(fileUri))
 .skipMemoryCache()
 .placeholder(R.drawable.placeholder)
 .stableKey(fileUri)
 .into(imageview);
</code></pre>

Then, you can clear the cache of this file later by calling this:

<pre><code>Picasso.with(getContext()).invalidate(fileUri);
</code></pre>

Hope this will help.

blocks|key|149116|text|你可以通过skipMemoryCache()跳过内存缓存|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|149117|请参阅以下内容|149118|++++++++Picasso.with(this)
++++++++++++.load(IMAGE_URL)
++++++++++++.skipMemoryCache()
++++++++++++.placeholder(R.drawable.placeholder)
++++++++++++.error(R.drawable.no_image)
++++++++++++.into(mImageViewPicasso);|code-block|syntax|javascript|149119|gradle+compile+"com.squareup.picasso:picasso:2.4.0"|149120|entityMap^0|5|H|0|0|0|7|18|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|T|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|U|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|V|8|@$9|W|A|X|B|C]]|D|@]|E|$]]|$1|O|3|-4|5|6|7|Y|8|@]|D|@]|E|$]]]|P|$]]

You can skip memory cache by <code>skipMemoryCache()</code>

see the following

<pre><code> Picasso.with(this)
 .load(IMAGE_URL)
 .skipMemoryCache()
 .placeholder(R.drawable.placeholder)
 .error(R.drawable.no_image)
 .into(mImageViewPicasso);
</code></pre>

gradle <code>compile "com.squareup.picasso:picasso:2.4.0"</code>

blocks|key|148595|text|另一种选择是将新图像保存到与原始图像不同的文件中。由于Picasso位图缓存与文件路径无关，因此从其他文件加载新图像将导致缓存未命中。这也有一个好处，即不必清除整个缓存。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|148596|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Another option is to save the new image into a different file than the original. Since the Picasso bitmap cache is keyed off of the file path, loading the new image from a different file will result in a cache miss. This also has the side benefit of not having to clear the entire cache.

blocks|key|4655467|text|根据源代码使用shutdown()；关闭将停止接受进一步的请求，并清除所有缓存|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4655468|+/**+Stops+this+instance+from+accepting+further+requests.+*/
++public+void+shutdown()+{
++++if+(this+==+singleton)+{
++++++throw+new+UnsupportedOperationException("Default+singleton+instance+cannot+be+shutdown.");
++++}
++++if+(shutdown)+{
++++++return;
++++}
++++cache.clear();
++++cleanupThread.shutdown();
++++stats.shutdown();
++++dispatcher.shutdown();
++++for+(DeferredRequestCreator+deferredRequestCreator+:+targetToDeferredRequestCreator.values())+{
++++++deferredRequestCreator.cancel();
++++}
++++targetToDeferredRequestCreator.clear();
++++shutdown+=+true;
++}|code-block|syntax|javascript|4655469|此外，您不能关闭单例实例。因此，您需要拥有Picasso的实例变量。不要忘记在每次shutdown()时重新初始化毕加索实例，以便重用它|4655470|entityMap^0|7|A|0|0|L|7|15|A|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@]|E|$]]|$1|M|3|-4|5|6|7|X|8|@]|D|@]|E|$]]]|N|$]]

use <code>shutdown()</code> instead
As per source code; shutdown will stop accepting further request as well as clear all cache

<pre><code> /** Stops this instance from accepting further requests. */
 public void shutdown() {
 if (this == singleton) {
 throw new UnsupportedOperationException("Default singleton instance cannot be shutdown.");
 }
 if (shutdown) {
 return;
 }
 cache.clear();
 cleanupThread.shutdown();
 stats.shutdown();
 dispatcher.shutdown();
 for (DeferredRequestCreator deferredRequestCreator : targetToDeferredRequestCreator.values()) {
 deferredRequestCreator.cancel();
 }
 targetToDeferredRequestCreator.clear();
 shutdown = true;
 }
</code></pre>

Also you can not shutdown singleton instance.
So you need to have instance variable for <code>Picasso</code>. Do not forget to reinitialize picasso instance everytime you <code>shutdown()</code> it in order to reuse it

blocks|key|4655478|text|File+f+=+new+File(path,+name);
Picasso.with(this).invalidate(Uri.fromFile(f));|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|4655479|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>File f = new File(path, name);
Picasso.with(this).invalidate(Uri.fromFile(f));
</code></pre>

I load an image from disk using <a href="http://square.github.io/picasso/">Picasso</a>, e.g., <code>Picasso.with(ctx).load(new File("/path/to/image")).into(imageView)</code>, but whenever I save a new image in that file, and refresh my <code>ImageView</code>, Picasso still has the bitmap cached. 

Is it possible to invalidate the cache in Picasso?

Invalidate cache in Picasso

我使用 (例如Picasso.with(ctx).load(new File("/path/to/image")).into(imageView) )从磁盘加载图像，但每当我在该文件中保存新图像并刷新我的ImageView时，毕加索仍然缓存了位图。有没有可能使毕加索的缓存失效？

问使毕加索中的缓存无效
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