Glide 4.0由Google的各種團隊內部使用，4.0被認為是內部穩定的。但外部用戶可能會發現內部尚未發現的問題。因此，將此作為RC發布。如果沒有發現穩定性或API中的重大問題，預計不久之后就會發布非RC版本。
一、集成
1、project gradle
repositories { mavenLocal() }2、app gradle
compile 'com.android.support:support-v4:25.3.1'compile 'com.github.bumptech.glide:glide:4.0.0'annotationProcessor 'com.github.bumptech.glide:compiler:4.0.0'
3、混淆
#glide4.0-keep public class * implements com.bumptech.glide.module.GlideModule-keep public class * extends com.bumptech.glide.AppGlideModule-keep public enum com.bumptech.glide.load.resource.bitmap.ImageHeaderParser$** { **[] $VALUES; public *;}# for DexGuard only-keepresourcexmlelements manifest/application/meta-data@value=GlideModule# 從glide4.0開始，GifDrawable沒有提供getDecoder()方法，# 需要通過反射獲取gifDecoder字段值，所以需要保持GifFrameLoader和GifState類不被混淆-keep class com.bumptech.glide.load.resource.gif.GifDrawable$GifState{*;}-keep class com.bumptech.glide.load.resource.gif.GifFrameLoader {*;}4、在4.0中不用像3.X需要在AndroidManifest.xml配置GlideModule，而是通過注解繼承AppGlideModule的子類來配置。
@GlideModulepublic class GlideConfiguration extends AppGlideModule { @Override public void applyOptions(Context context, GlideBuilder builder) { //自定義緩存目錄，磁盤緩存給150M 另外一種設置緩存方式 builder.setDiskCache(new InternalCacheDiskCacheFactory(context, "GlideImgCache", 150 * 1024 * 1024)); //配置圖片緩存格式 默認格式為8888 builder.setDefaultRequestOptions(RequestOptions.formatOf(DecodeFormat.PREFER_ARGB_8888)); ViewTarget.setTagId(R.id.glide_tag_id); } /** * 禁止解析Manifest文件 * 主要針對V3升級到v4的用戶，可以提升初始化速度，避免一些潛在錯誤 * @return */ @Override public boolean isManifestParsingEnabled() { return false; }}二、使用注意事項
1、使用GlideApp代替Glide，asBitmap、asGif、asDrawable、asFile都要放到load之前（glide3.7.0都是要在load之后調用）。
public static void loadImg(Context context,String url, ImageView imageView){ GlideApp.with(context) .asBitmap() .load(url) .placeholder(R.drawable.placeholder) //設置資源加載過程中的占位符 .into(imageView); }2、占位符.placeholder(R.drawable.placeholder)不能用.9圖，占位圖片和加載的目標圖片會同時顯示，只是目標圖片會先顯示縮略圖，然后顯示正常。fallback和error還沒測試過，有興趣的可以測試看看。
3、加載gif圖時，若調用dontAnimate()移除所有動畫，gif就會加載失敗。
4、計算gif播放一次的動畫時長。
glide 3.7.0你可以這樣獲取動畫時長：
public void loadGif(Context context,ImageView mIvGif,int url){ Glide.with(context) .load(url) .listener(new RequestListener<Integer, GlideDrawable>() { @Override public boolean onException(Exception e, Integer model, Target<GlideDrawable> target, boolean isFirstResource) { return false; } @Override public boolean onResourceReady(GlideDrawable resource, Integer model, Target<GlideDrawable> target, boolean isFromMemoryCache, boolean isFirstResource) { try { int duration = 0; GifDrawable gifDrawable = (GifDrawable) resource; GifDecoder decoder = gifDrawable.getDecoder(); for (int i = 0; i < gifDrawable.getFrameCount(); i++) { duration += decoder.getDelay(i); } Log.e("Glide3.7.0","gif播放一次動畫時長duration:"+duration); } catch (Throwable e) { } return false; } }) .into(new GlideDrawableImageViewTarget(mIvGif, 1)); }glide4.0中GifDrawable沒有提供getDecoder()方法并且還去掉了decoder這個成員變量。除此之外，glide4.0還去掉了GlideDrawableImageViewTarget類，那我們該如何來計算gif播放一次的時長呢？只能從源碼中找答案了。
（1）尋找decoder
glide3.7.0 GifDrawable中我們可以發現decoder最終于會傳入GifFrameLoader類中并賦值給gifDecoder變量。
//源碼//glide 3.7.0 GifDrawable.java GifDrawable(GifState state) { if (state == null) { throw new NullPointerException("GifState must not be null"); } this.state = state; this.decoder = new GifDecoder(state.bitmapProvider); this.paint = new Paint(); decoder.setData(state.gifHeader, state.data); frameLoader = new GifFrameLoader(state.context, this, decoder, state.targetWidth, state.targetHeight); frameLoader.setFrameTransformation(state.frameTransformation); }/*---------------------------------------------------------------------------------------------------*///glide 3.7.0 GifFrameLoader.javaprivate final GifDecoder gifDecoder;//私有屬性public GifFrameLoader(Context context, FrameCallback callback, GifDecoder gifDecoder, int width, int height) { this(callback, gifDecoder, null, getRequestBuilder(context, gifDecoder, width, height, Glide.get(context).getBitmapPool())); } GifFrameLoader(FrameCallback callback, GifDecoder gifDecoder, Handler handler, GenericRequestBuilder<GifDecoder, GifDecoder, Bitmap, Bitmap> requestBuilder) { if (handler == null) { handler = new Handler(Looper.getMainLooper(), new FrameLoaderCallback()); } this.callback = callback; //看這里 this.gifDecoder = gifDecoder; this.handler = handler; this.requestBuilder = requestBuilder; }glide4.0 GifDrawable類的構造中我們可以看到有一個gifDecoder的參數，這個參數的解釋是解碼器用于解碼GIF數據（The decoder to use to decode GIF data）。繼續看這個構造，發現gifDecoder最終也是被傳到GifFrameLoader類中并賦值給gifDecoder變量。所以glide3.7.0中的decoder其實就是4.0中的gifDecoder。
//源碼//glide 4.0 GifDrawable.javaprivate final GifState state;/* * @param gifDecoder The decoder to use to decode GIF data. * @param firstFrame The decoded and transformed first frame of this GIF. * @see #setFrameTransformation(com.bumptech.glide.load.Transformation, android.graphics.Bitmap) */ public GifDrawable(Context context, GifDecoder gifDecoder, BitmapPool bitmapPool, Transformation<Bitmap> frameTransformation, int targetFrameWidth, int targetFrameHeight, Bitmap firstFrame) { this( new GifState( bitmapPool, new GifFrameLoader( // TODO(b/27524013): Factor out this call to Glide.get() Glide.get(context), gifDecoder, targetFrameWidth, targetFrameHeight, frameTransformation, firstFrame))); }/*---------------------------------------------------------------------------------------------*///glide4.0 GifFrameLoader.javaprivate final GifDecoder gifDecoder;//私有屬性 public GifFrameLoader( Glide glide, GifDecoder gifDecoder, int width, int height, Transformation<Bitmap> transformation, Bitmap firstFrame) { this( glide.getBitmapPool(), Glide.with(glide.getContext()), gifDecoder, null /*handler*/, getRequestBuilder(Glide.with(glide.getContext()), width, height), transformation, firstFrame); } @SuppressWarnings("PMD.ConstructorCallsOverridableMethod") GifFrameLoader( BitmapPool bitmapPool, RequestManager requestManager, GifDecoder gifDecoder, Handler handler, RequestBuilder<Bitmap> requestBuilder, Transformation<Bitmap> transformation, Bitmap firstFrame) { this.requestManager = requestManager; if (handler == null) { handler = new Handler(Looper.getMainLooper(), new FrameLoaderCallback()); } this.bitmapPool = bitmapPool; this.handler = handler; this.requestBuilder = requestBuilder; //看這里 this.gifDecoder = gifDecoder; setFrameTransformation(transformation, firstFrame); }（2）獲取decoder
從上面Glide4.0的GifDrawable構造中可以看到gifDecoder被傳遞到GifFrameLoader中賦值給私有屬性gifDecoder;，而GifFrameLoader又被傳入GifState中并被賦值給它的成員變量frameLoader，那要怎么獲取frameLoader？
從源碼中，可以看到GifDrawable提供了getConstantState()方法來獲取state變量（這個變量的類型就是GifState），但是GifState并沒有get方法獲取frameLoader，frameLoader對象中的gifDecoder也是私有，也沒有提供get方法來獲取，那么我們只能通過反射來獲取了。
//源碼//glide4.0 GifDrawable.javaprivate final GifState state; @Override public ConstantState getConstantState() { return state; } static class GifState extends ConstantState { static final int GRAVITY = Gravity.FILL; final BitmapPool bitmapPool; final GifFrameLoader frameLoader; public GifState(BitmapPool bitmapPool, GifFrameLoader frameLoader) { this.bitmapPool = bitmapPool; this.frameLoader = frameLoader; } @Override public Drawable newDrawable(Resources res) { return newDrawable(); } @Override public Drawable newDrawable() { return new GifDrawable(this); } @Override public int getChangingConfigurations() { return 0; } }通過反射來獲取獲取decoder
.listener(new RequestListener<GifDrawable>() { @Override public boolean onLoadFailed(@Nullable GlideException e, Object model, Target<GifDrawable> target, boolean isFirstResource) { return false; } @Override public boolean onResourceReady(GifDrawable gifDrawable, Object model, Target<GifDrawable> target, DataSource dataSource, boolean isFirstResource) { try { int duration = 0; // 計算動畫時長 //GifDecoder decoder = gifDrawable.getDecoder();//4.0開始沒有這個方法了 Drawable.ConstantState state = gifDrawable.getConstantState(); if(state!=null){ //不能混淆GifFrameLoader和GifState類 Object gifFrameLoader = getValue(state,"frameLoader"); if(gifFrameLoader!=null){ Object decoder = getValue(gifFrameLoader,"gifDecoder"); if(decoder!=null && decoder instanceof GifDecoder){ for (int i = 0; i < gifDrawable.getFrameCount(); i++) { duration += ((GifDecoder) decoder).getDelay(i); } } } Log.e("Glide4.0","gif播放動畫時長duration:"+duration); } } catch (Throwable e) { } return false; } })/*---------------------------------------------------------------------------------------------*//** * 通過字段名從對象或對象的父類中得到字段的值 * @param object 對象實例 * @param fieldName 字段名 * @return 字段對應的值 * @throws Exception */ public static Object getValue(Object object, String fieldName) throws Exception { if (object == null) { return null; } if (TextUtils.isEmpty(fieldName)) { return null; } Field field = null; Class<?> clazz = object.getClass(); for (; clazz != Object.class; clazz = clazz.getSuperclass()) { try { field = clazz.getDeclaredField(fieldName); field.setAccessible(true); return field.get(object); } catch (Exception e) { //這里甚么都不要做！并且這里的異常必須這樣寫，不能拋出去。 //如果這里的異常打印或者往外拋，則就不會執行clazz = clazz.getSuperclass(),最后就不會進入到父類中了 } } return null; }(3)設置gif循環播放次數
glide4.0中沒有GlideDrawableImageViewTarget類，那么怎么設置循環播放次數呢？
從glide3.7.0源碼可以發現GlideDrawableImageViewTarget是通過GlideDrawable的setLoopCount方法來設置循環播放次數的，查看setLoopCount具體實現地方是在GifDrawable，所以這里調用的其實是GifDrawable的setLoopCount方法。glide4.0中沒有GlideDrawable類和GlideDrawableImageViewTarget類，但是仍然有GifDrawable類，并且onResourceReady方法中第一個參數就是GifDrawable，所以可以直接調用GifDrawable的setLoopCount(loopCount)來設置播放次數。
//源碼//3.7.0 GlideDrawableImageViewTarget.java public GlideDrawableImageViewTarget(ImageView view, int maxLoopCount) { super(view); this.maxLoopCount = maxLoopCount; } @Override public void onResourceReady(GlideDrawable resource, GlideAnimation<? super GlideDrawable> animation) { if (!resource.isAnimated()) { //TODO: Try to generalize this to other sizes/shapes. // This is a dirty hack that tries to make loading square thumbnails and then square full images less costly // by forcing both the smaller thumb and the larger version to have exactly the same intrinsic dimensions. // If a drawable is replaced in an ImageView by another drawable with different intrinsic dimensions, // the ImageView requests a layout. Scrolling rapidly while replacing thumbs with larger images triggers // lots of these calls and causes significant amounts of jank. float viewRatio = view.getWidth() / (float) view.getHeight(); float drawableRatio = resource.getIntrinsicWidth() / (float) resource.getIntrinsicHeight(); if (Math.abs(viewRatio - 1f) <= SQUARE_RATIO_MARGIN && Math.abs(drawableRatio - 1f) <= SQUARE_RATIO_MARGIN) { resource = new SquaringDrawable(resource, view.getWidth()); } } super.onResourceReady(resource, animation); this.resource = resource; //********看這里****** //android studio可以通過快捷鍵Ctrl+Alt+B查看其實現 resource.setLoopCount(maxLoopCount); resource.start(); }glide4.0 計算gif一次播放時長代碼：
public static void loadGifImg(Context context,String url, ImageView imageView){ GlideApp.with(context) .asGif() .load(url) .placeholder(R.drawable.placeholder) .fallback(R.drawable.fallback) .listener(new RequestListener<GifDrawable>() { @Override public boolean onLoadFailed(@Nullable GlideException e, Object model, Target<GifDrawable> target, boolean isFirstResource) { return false; } @Override public boolean onResourceReady(GifDrawable gifDrawable, Object model, Target<GifDrawable> target, DataSource dataSource, boolean isFirstResource) { try { //設置循環播放次數為1次 gifDrawable.setLoopCount(1); // 計算動畫時長 int duration = 0; //GifDecoder decoder = gifDrawable.getDecoder();//4.0開始沒有這個方法了 Drawable.ConstantState state = gifDrawable.getConstantState(); if(state!=null){ //不能混淆GifFrameLoader和GifState類 Object gifFrameLoader = getValue(state,"frameLoader"); if(gifFrameLoader!=null){ Object decoder = getValue(gifFrameLoader,"gifDecoder"); if(decoder!=null && decoder instanceof GifDecoder){ for (int i = 0; i < gifDrawable.getFrameCount(); i++) { duration += ((GifDecoder) decoder).getDelay(i); } } } Log.e("Glide4.0","gif播放一次動畫時長duration:"+duration); } } catch (Throwable e) { } return false; } }) .into(imageView); }注意：因為用了反射獲取decoder，所以不能混淆GifFrameLoader和GifState類
5、設置淡入淡出動畫
glide3.7.0
Glide.with(context) .load(url) .crossFade(100) //系統漸變動畫 .placeholder(R.drawable.placeholder) .fallback(R.drawable.fallback) .diskCacheStrategy(DiskCacheStrategy.ALL) .into(imageView);
glide4.0
GlideApp.with(context) .load(url) .transition(DrawableTransitionOptions.withCrossFade(100))//淡入淡出100m .placeholder(R.drawable.placeholder) .fallback(R.drawable.fallback) .diskCacheStrategy(DiskCacheStrategy.ALL) .into(imageView);
6、緩存策略
glide3.7.0
//DiskCacheStrategy.SOURCE：緩存原始數據//DiskCacheStrategy.RESULT：緩存變換(如縮放、裁剪等)后的資源數據//DiskCacheStrategy.NONE：什么都不緩存//DiskCacheStrategy.ALL：緩存SOURC和RESULT//默認采用DiskCacheStrategy.RESULT策略，對于download only操作要使用DiskCacheStrategy.SOURCE
glide4.0
//DiskCacheStrategy.ALL 使用DATA和RESOURCE緩存遠程數據，僅使用RESOURCE來緩存本地數據。// DiskCacheStrategy.NONE 不使用磁盤緩存// DiskCacheStrategy.DATA 在資源解碼前就將原始數據寫入磁盤緩存// DiskCacheStrategy.RESOURCE 在資源解碼后將數據寫入磁盤緩存，即經過縮放等轉換后的圖片資源。// DiskCacheStrategy.AUTOMATIC 根據原始圖片數據和資源編碼策略來自動選擇磁盤緩存策略。//默認采用DiskCacheStrategy.AUTOMATIC策略/*-------------------------------------------------------------------------------*///源碼 RequestOptions.javaprivate DiskCacheStrategy diskCacheStrategy = DiskCacheStrategy.AUTOMATIC;
7、占位符、錯誤圖片設置
glide4.0 若into中設置的是target，占位符（placeholder、error）需要在回調中再次設置，否則無效。
public static void loadImg(String url, ImageView imageView) { //into中用Target，占位符（placeholder、error）需要在回調中設置 GlideApp.with(FanhuanApplication.getInstance().getApplication()) .asBitmap() .load(url) .placeholder(drawbleId) //設置資源加載過程中的占位符 .fallback(drawbleId) .error(drawbleId) .diskCacheStrategy(DiskCacheStrategy.ALL) .into(new SimpleTarget<Bitmap>() { @Override public void onResourceReady(Bitmap resource, Transition<? super Bitmap> transition) { imageView.setImageBitmap(resource); } @Override public void onLoadFailed(@Nullable Drawable errorDrawable) { super.onLoadFailed(errorDrawable); if(errorDrawable!=null){ imageView.setImageDrawable(errorDrawable); } } @Override public void onLoadStarted(@Nullable Drawable placeholder) { super.onLoadStarted(placeholder); if(placeholder!=null){ imageView.setImageDrawable(placeholder); } } }); }以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持VEVB武林網。
新聞熱點
疑難解答
