Volley涓婚〉 https://android.googlesource.com/platform/frameworks/volley
http://www.youtube.com/watch?v=yhv8l9F44qo&feature=player_embedded
1. 浠?涔堟槸Volley
鍦ㄨ繖涔嬪墠锛屾垜浠?湪绋嬪簭涓?渶瑕佸拰缃戠粶閫氫俊鐨勬椂鍊欙紝澶т綋浣跨敤鐨勪笢瑗胯帿杩囦簬AsyncTaskLoader锛孒ttpURLConnection锛孉syncTask锛孒TTPClient锛圓pache锛夌瓑锛屼粖骞寸殑Google I/O 2013涓婏紝Volley鍙戝竷浜嗐?俈olley鏄疉ndroid骞冲彴涓婄殑缃戠粶閫氫俊搴擄紝鑳戒娇缃戠粶閫氫俊鏇村揩锛屾洿绠?鍗曪紝鏇村仴澹???
杩欐槸Volley鍚嶇О鐨勭敱鏉ワ細 a burst or emission of many things or a large amount at once
鍦℅oogle IO鐨勬紨璁蹭笂锛屽叾閰嶅浘鏄?竴骞呭彂灏勭伀寮撶?鐨勫浘锛屾湁鐐圭被浼兼祦鏄熴?傝?涓嬪浘
鍏跺疄锛屼粠杩欏箙鍥撅紝鎴戜滑涔熷彲浠ョ湅鍑烘潵锛孷olley鐗瑰埆閫傚悎鏁版嵁閲忎笉澶т絾鏄??氫俊棰戠箒鐨勫満鏅???
1.1. Volley寮曞叆鐨勮儗鏅?
鍦ㄤ互鍓嶏紝鎴戜滑鍙?兘闈?复濡備笅寰堝?楹荤儲鐨勯棶棰樸??
姣斿?浠ュ墠浠庣綉涓婁笅杞藉浘鐗囩殑姝ラ?鍙?兘鏄?繖鏍风殑娴佺▼锛?
- 鍦↙istAdapter#getView()閲屽紑濮嬪浘鍍忕殑璇诲彇銆?
- 閫氳繃AsyncTask绛夋満鍒朵娇鐢℉ttpURLConnection浠庢湇鍔″櫒鍘荤殑鍥剧墖璧勬簮
- 鍦ˋsyncTask#onPostExecute()閲岃?缃?浉搴擨mageView鐨勫睘鎬с??
鑰屽湪Volley涓嬶紝鍙?渶瑕佷竴涓?嚱鏁板嵆鍙?紝璇︾粏瑙佸悗闈㈢殑渚嬪瓙銆?
鍐嶆瘮濡傦紝灞忓箷鏃嬭浆鐨勬椂鍊欙紝鏈夋椂鍊欎細瀵艰嚧鍐嶆?浠庣綉缁滃彇寰楁暟鎹??備负浜嗛伩鍏嶈繖绉嶄笉蹇呰?鐨勭綉缁滆?闂?紝鎴戜滑鍙?兘闇?瑕佽嚜宸卞啓寰堝?閽堝?鍚勭?鎯呭喌鐨勫?鐞嗭紝姣斿?cache浠?涔堢殑銆?
鍐嶆湁锛屾瘮濡侺istView鐨勬椂鍊欙紝鎴戜滑婊氬姩杩囧揩锛屽彲鑳藉?鑷存湁浜涚綉缁滆?姹傝繑鍥炵殑鏃跺?欙紝鏃╁凡缁忔粴杩囦簡褰撴椂鐨勪綅缃?紝鏍规湰娌″繀瑕佹樉绀哄湪list閲屼簡锛岃櫧鐒舵垜浠?彲浠ラ?氳繃ViewHolder鏉ヤ繚鎸乽rl绛夋潵瀹炵幇闃叉?涓ゆ?鍙栧緱锛屼絾鏄?偅浜涘凡缁忔病鏈夊繀椤昏?鐨勬暟鎹?紝杩樻槸浼氭氮璐圭郴缁熺殑鍚勭?璧勬簮銆?
1.2. Volley鎻愪緵鐨勫姛鑳?
绠?鍗曟潵璇达紝瀹冩彁渚涗簡濡備笅鐨勪究鍒╁姛鑳斤細
- JSON锛屽浘鍍忕瓑鐨勫紓姝ヤ笅杞斤紱
- 缃戠粶璇锋眰鐨勬帓搴忥紙scheduling锛?
- 缃戠粶璇锋眰鐨勪紭鍏堢骇澶勭悊
- 缂撳瓨
- 澶氱骇鍒?彇娑堣?姹?
- 鍜孉ctivity鍜岀敓鍛藉懆鏈熺殑鑱斿姩锛圓ctivity缁撴潫鏃跺悓鏃跺彇娑堟墍鏈夌綉缁滆?姹傦級
2. 浣跨敤鍓嶇殑鍑嗗?
寮曞叆Volley闈炲父绠?鍗曪紝棣栧厛锛屼粠git搴撳厛鍏嬮殕涓?涓?笅鏉ワ細
寮曠敤
git clone https://android.googlesource.com/platform/frameworks/volley
鐒跺悗缂栬瘧涓簀ar鍖咃紝鍐嶅湪鑷?繁鐨勫伐绋嬮噷import杩涙潵銆?
娉ㄦ剰锛岃繖涓?簱瑕佹眰鏈?浣嶴DK鐗堟湰涓篎royo锛屽嵆鑷冲皯瑕佽?缃產ndroid:minSdkVersion涓?浠ヤ笂銆?
3.浣跨敤渚嬪瓙
涓嬮潰绠?鍗曠湅鐪嬪?浣曚娇鐢╒olley
3.1. 鏈?绠?鍗曠殑get璇锋眰
杩欎釜渚嬪瓙寰堢畝鍗曪紝浠庣綉缁滃彇寰桱SON瀵硅薄锛岀劧鍚庢墦鍗板嚭鏉ャ??
mQueue = Volley.newRequestQueue(getApplicationContext());mQueue.add(new JsonObjectRequest(Method.GET, url, null, new Listener() { @Override public void onResponse(JSONObject response) { Log.d(TAG, "response : " + response.toString()); } }, null));mQueue.start();3.2. 缁橧mageView璁剧疆鍥剧墖婧?
// imageView鏄?竴涓狪mageView瀹炰緥 // ImageLoader.getImageListener鐨勭?浜屼釜鍙傛暟鏄?粯璁ょ殑鍥剧墖resource id // 绗?笁涓?弬鏁版槸璇锋眰澶辫触鏃跺?欑殑璧勬簮id锛屽彲浠ユ寚瀹氫负0 ImageListener listener = ImageLoader.getImageListener(imageView, android.R.drawable.ic_menu_rotate, android.R.drawable.ic_delete); mImageLoader.get(url, listener);
ImageLoader鐨勬柟娉曢兘闇?瑕佷粠涓荤嚎绋嬮噷鏉ヨ皟鐢ㄣ??
3.3. 浣跨敤NetworkImageView
Volley鎻愪緵浜嗕竴涓?柊鐨勬帶浠禢etworkImageView鏉ヤ唬鏇夸紶缁熺殑ImageView锛岃繖涓?帶浠剁殑鍥剧墖灞炴?у彲浠ラ?氳繃
mImageView.setImageUrl(url, imageLoader)
鏉ヨ?瀹氥?傝?屼笖锛岃繖涓?帶浠跺湪琚?粠鐖舵帶浠禿etach鐨勬椂鍊欙紝浼氳嚜鍔ㄥ彇娑堢綉缁滆?姹傜殑锛屽嵆瀹屽叏涓嶇敤鎴戜滑鎷呭績鐩稿叧缃戠粶璇锋眰鐨勭敓鍛藉懆鏈熼棶棰樸??
绀轰緥浠ｇ爜濡備笅锛?
mImageLoader = new ImageLoader(mRequestQueue, new BitmapLruCache()); ... ... if(holder.imageRequest != null) { holder.imageRequest.cancel(); } holder.imageRequest = mImageLoader.get(BASE_UR + item.image_url, holder.imageView, R.drawable.loading, R.drawable.error);娉ㄦ剰锛岃繖閲屼娇鐢ㄧ殑涓嶆槸ImageView鎺т欢锛岃?屾槸Volley鏂版彁渚涚殑com.android.volley.NetworkImageView銆?
鍙﹀?锛屾敞鎰忚繖閲岋細
mImageLoader = new ImageLoader(mRequestQueue, new BitmapLruCache());
ImageLoader鏋勯?犲嚱鏁扮殑绗?簩涓?弬鏁版槸涓?涓狪mageCache鐨勫疄渚嬶紙涓ユ牸鏉ヨ?锛屾槸瀹炵幇ImageCache鎺ュ彛鐨勬煇鍏蜂綋绫荤殑瀹炰緥锛?
ImageCache鐨勫畾涔夊?涓嬶紙鍦↖mageLoader.java閲岋級锛?
/** * Simple cache adapter interface. If provided to the ImageLoader, it * will be used as an L1 cache before dispatch to Volley. Implementations * must not block. Implementation with an LruCache is recommended. */ public interface ImageCache { public Bitmap getBitmap(String url); public void putBitmap(String url, Bitmap bitmap); }涓嬮潰鐨勭綉鍧?涓?涓猯ru鐨刢ache瀹炵幇渚嬪瓙锛岃?鍙傝?冿細
https://github.com/suwa-yuki/VolleySample/blob/master/src/jp/classmethod/android/sample/volley/BitmapCache.java
3.5. 浣跨敤鑷?繁瀹氬埗鐨剅equest
鎴戜滑涔熷彲浠ラ?氳繃缁ф壙Request鏍规嵁鑷?繁鐨勯渶姹傛潵瀹氬埗鑷?繁鐨剅equest
@Override protected Response parseNetworkResponse(NetworkResponse response) { try { String json = new String( response.data, HttpHeaderParser.parseCharset(response.headers)); return Response.success( gson.fromJson(json, clazz), HttpHeaderParser.parseCacheHeaders(response)); } catch (UnsupportedEncodingException e) { return Response.error(new ParseError(e)); } catch (JsonSyntaxException e) { return Response.error(new ParseError(e)); } }杩欐?浠ｇ爜鑺傞?夎嚜锛?https://gist.github.com/ficusk/5474673
閲岄潰浣跨敤鐨刧son锛坈om.google.gson.Gson锛夋槸JSON鐨勫簭鍒楀寲鍜屽弽搴忓垪鍖栫殑搴擄紝鍙?互鍦↗SON鍜宩ava model object涔嬮棿杩涜?杞?崲銆?
浠ヤ笅鏄?娇鐢ㄨ嚜瀹氬埗request鐨勪緥瀛愶細
mRequestQueue.add( new GsonRequest(url, ListResponse.class, null, new Listener() { public void onResponse(ListResponse response) { appendItemsToList(response.item); notifyDataSetChanged(); } } }4. Volley鐨勬灦鏋勮?璁?
Volley浣跨敤浜嗙嚎绋嬫睜鏉ヤ綔涓哄熀纭?缁撴瀯锛屼富瑕佸垎涓轰富绾跨▼锛宑ache绾跨▼鍜宯etwork绾跨▼銆?
涓荤嚎绋嬪拰cache绾跨▼閮藉彧鏈変竴涓?紝鑰孨etworkDispatcher绾跨▼鍙?互鏈夊?涓?紝杩欐牱鑳借В鍐虫瘮骞惰?闂??銆傚?涓嬪浘:
濡傛灉鍦ㄤ竴涓狝ctivity閲岄潰鍚?姩浜嗙綉缁滆?姹傦紝鑰屽湪杩欎釜缃戠粶璇锋眰杩樻病杩斿洖缁撴灉鐨勬椂鍊欙紝濡傛灉Activity琚?粨鏉熶簡锛屽垯鎴戜滑闇?瑕佸啓濡備笅浠ｇ爜浣滀负闃插畧锛?
@Override public void onPostExecute(Result r) { if (getActivity() == null) { return; } // ... }Activity琚?粓姝?箣鍚庯紝濡傛灉缁х画浣跨敤鍏朵腑鐨凜ontext绛夛紝闄や簡鏃犺緶鐨勬氮璐笴PU锛岀數姹狅紝缃戠粶绛夎祫婧愶紝鏈夊彲鑳借繕浼氬?鑷寸▼搴廲rash锛屾墍浠ワ紝鎴戜滑闇?瑕佸?鐞嗚繖绉嶄竴鍦烘儏鍐点??
浣跨敤Volley鐨勮瘽锛屾垜浠?彲浠ュ湪Activity鍋滄?鐨勬椂鍊欙紝鍚屾椂鍙栨秷鎵?鏈夋垨閮ㄥ垎鏈?畬鎴愮殑缃戠粶璇锋眰銆?
Volley閲屾墍鏈夌殑璇锋眰缁撴灉浼氳繑鍥炵粰涓昏繘绋嬶紝濡傛灉鍦ㄤ富杩涚▼閲屽彇娑堜簡鏌愪簺璇锋眰锛屽垯杩欎簺璇锋眰灏嗕笉浼氳?杩斿洖缁欎富绾跨▼銆?
姣斿?锛屽彲浠ラ拡瀵规煇浜涗釜request鍋氬彇娑堟搷浣滐細
@Override public void onStop() { for (Request <?> req : mInFlightRequests) { req.cancel(); } ... }鎴栬?咃紝鍙栨秷杩欎釜闃熷垪閲岀殑鎵?鏈夎?姹傦細
@Override pubic void onStop() { mRequestQueue.cancelAll(this); ... }涔熷彲浠ユ牴鎹甊equestFilter鎴栬?匱ag鏉ョ粓姝㈡煇浜涜?姹傦細
@Override public void onStop() { mRequestQueue.cancelAll( new RequestFilter() {}) ... // or mRequestQueue.cancelAll(new Object()); ...5.鎬荤粨
浠庢紨璁茬殑渚嬪瓙鏉ョ湅锛孷olley搴旇?鏄?畝鍖栦簡缃戠粶閫氫俊鐨勪竴浜涘紑鍙戯紝鐗瑰埆鏄?拡瀵瑰?涓嬩袱绉嶆儏鍐碉細
- JSON瀵硅薄
- 鍥剧墖鍔犺浇
浣嗘槸杩欎釜涓滆タ涔熸湁涓嶅疄鐢ㄧ殑鍦版柟锛屾瘮濡傚ぇ鏁版嵁锛坙arge payloads 锛夛紝娴佸獟浣擄紝杩欎簺case锛岃繕闇?瑕佷娇鐢ㄥ師濮嬬殑鏂规硶锛屾瘮濡侱ownload Manager绛夈??
鎬讳箣锛屽?鏋滀綘瑕佺紪鍐欑綉缁滅▼搴忥紝鏄?笉鏄?彲浠ヨ?冭檻寮?濮嬩娇鐢╒olley鍛?紵
git涓婄殑涓?渚?
https://github.com/suwa-yuki/VolleySample/tree/master/src/jp/classmethod/android/sample