sychaos/-READ-glide

An image loading and caching library for Android focused on smooth scrolling

Glide

解析

如果你是在子线程调用with方法,或者传入的Context是Application的话,请求是跟你的Application的生命周期同步，如果有指定的activity或者fragment会创建一个无界面的Fragment 1.Util.assertMainThread();这里会检查是否主线程,不是的话会抛出异常,所以into方法必须在主线程中调用. 2.当你没有调用transform方法,并且你的ImageView设置了ScaleType,那么他会根据你的设置,对图片做处理(具体处理可以查看DrawableRequestBuilder的applyCenterCrop或者applyFitCenter方法,我们自己自定义BitmapTransformation也可以参考这里的处理). 3.这里可以看到控件封装成的Target能够获取自身绑定的请求,当发现之前的请求还在的时候,会把旧的请求清除掉,绑定新的请求,这也就是为什么控件复用时不会出现图片错位的问题(这点跟我在Picasso源码中看到的处理方式很相像)

load

1.首先会尝试从cache里面取,这里cache就是Glide的构造函数里面的MemoryCache(是一个LruResourceCache),如果取到了,就从cache里面删掉,然后加入activeResources中 2.如果cache里面没取到,就会从activeResources中取,activeResources是一个以弱引用为值的map,他是用于存储使用中的资源.之所以在内存缓存的基础上又多了这层缓存,是为了当内存不足而清除cache中的资源中,不会影响使用中的资源.

| View Glide's documentation | 简体中文文档 | Report an issue with Glide

Glide is a fast and efficient open source media management and image loading framework for Android that wraps media decoding, memory and disk caching, and resource pooling into a simple and easy to use interface.

Glide supports fetching, decoding, and displaying video stills, images, and animated GIFs. Glide includes a flexible API that allows developers to plug in to almost any network stack. By default Glide uses a custom HttpUrlConnection based stack, but also includes utility libraries plug in to Google's Volley project or Square's OkHttp library instead.

Glide's primary focus is on making scrolling any kind of a list of images as smooth and fast as possible, but Glide is also effective for almost any case where you need to fetch, resize, and display a remote image.

Download

You can download a jar from GitHub's releases page.

Or use Gradle:

repositories {
  mavenCentral()
  google()
}

dependencies {
  implementation 'com.github.bumptech.glide:glide:4.4.0'
  annotationProcessor 'com.github.bumptech.glide:compiler:4.4.0'
}

Or Maven:

<dependency>
  <groupId>com.github.bumptech.glide</groupId>
  <artifactId>glide</artifactId>
  <version>4.4.0</version>
</dependency>
<dependency>
  <groupId>com.google.android</groupId>
  <artifactId>support-v4</artifactId>
  <version>r7</version>
</dependency>
<dependency>
  <groupId>com.github.bumptech.glide</groupId>
  <artifactId>compiler</artifactId>
  <version>4.4.0</version>
  <optional>true</optional>
</dependency>

For info on using the bleeding edge, see the Snapshots docs page.

ProGuard

Depending on your ProGuard (DexGuard) config and usage, you may need to include the following lines in your proguard.cfg (see the Download and Setup docs page for more details):

-keep public class * implements com.bumptech.glide.module.GlideModule
-keep public class * extends com.bumptech.glide.module.AppGlideModule
-keep public enum com.bumptech.glide.load.resource.bitmap.ImageHeaderParser$** {
  **[] $VALUES;
  public *;
}

# for DexGuard only
-keepresourcexmlelements manifest/application/meta-data@value=GlideModule

How do I use Glide?

Check out the documentation for pages on a variety of topics, and see the javadocs.

For Glide v3, see the wiki.

Simple use cases with Glide's generated API will look something like this:

// For a simple view:
@Override public void onCreate(Bundle savedInstanceState) {
  ...
  ImageView imageView = (ImageView) findViewById(R.id.my_image_view);

  GlideApp.with(this).load("http://goo.gl/gEgYUd").into(imageView);
}

// For a simple image list:
@Override public View getView(int position, View recycled, ViewGroup container) {
  final ImageView myImageView;
  if (recycled == null) {
    myImageView = (ImageView) inflater.inflate(R.layout.my_image_view, container, false);
  } else {
    myImageView = (ImageView) recycled;
  }

  String url = myUrls.get(position);

  GlideApp
    .with(myFragment)
    .load(url)
    .centerCrop()
    .placeholder(R.drawable.loading_spinner)
    .into(myImageView);

  return myImageView;
}

Status

Version 4 is now released and stable. Updates are currently released at least monthly with new features and bug fixes.

Comments/bugs/questions/pull requests are always welcome! Please read CONTRIBUTING.md on how to report issues.

Compatibility

• Minimum Android SDK: Glide v4 requires a minimum API level of 14.
• Compile Android SDK: Glide v4 requires you to compile against API 26 or later.

If you need to support older versions of Android, consider staying on Glide v3, which works on API 10, but is not actively maintained.

• OkHttp 3.x: There is an optional dependency available called okhttp3-integration, see the docs page.
• Volley: There is an optional dependency available called volley-integration, see the docs page.
• Round Pictures: CircleImageView/CircularImageView/RoundedImageView are known to have issues with TransitionDrawable (.crossFade() with .thumbnail() or .placeholder()) and animated GIFs, use a BitmapTransformation (.circleCrop() will be available in v4) or .dontAnimate() to fix the issue.
• Huge Images (maps, comic strips): Glide can load huge images by downsampling them, but does not support zooming and panning ImageViews as they require special resource optimizations (such as tiling) to work without OutOfMemoryErrors.

Build

Building Glide with gradle is fairly straight forward:

git clone https://github.com/bumptech/glide.git 
cd glide
./gradlew jar

Note: Make sure your Android SDK has the Android Support Repository installed, and that your $ANDROID_HOME environment variable is pointing at the SDK or add a local.properties file in the root project with a sdk.dir=... line.

Samples

Follow the steps in the Build section to set up the project and then:

./gradlew :samples:flickr:run
./gradlew :samples:giphy:run
./gradlew :samples:svg:run
./gradlew :samples:contacturi:run

You may also find precompiled APKs on the releases page.

Development

Follow the steps in the Build section to setup the project and then edit the files however you wish. Android Studio cleanly imports both Glide's source and tests and is the recommended way to work with Glide.

To open the project in Android Studio:

1. Go to File menu or the Welcome Screen
2. Click on Open...
3. Navigate to Glide's root directory.
4. Select setting.gradle

For more details, see the Contributing docs page.

Getting Help

To report a specific problem or feature request, open a new issue on Github. For questions, suggestions, or anything else, email Glide's discussion group, or join our IRC channel: irc.freenode.net#glide-library.

Contributing

Before submitting pull requests, contributors must sign Google's individual contributor license agreement.

Thanks

• The Android team and Jake Wharton for the disk cache implementation Glide's disk cache is based on.
• Dave Smith for the GIF decoder gist Glide's GIF decoder is based on.
• Chris Banes for his gradle-mvn-push script.
• Corey Hall for Glide's amazing logo.
• Everyone who has contributed code and reported issues!

Author

Sam Judd - @sjudd on GitHub, @samajudd on Twitter

License

BSD, part MIT and Apache 2.0. See the LICENSE file for details.

Disclaimer

This is not an official Google product.