目錄介紹
- 01.原生跳轉實現
-
02.實現組件跳轉方式
- 2.1 傳統跳轉方式
- 2.2 爲何需要路由
- 03.ARouter配置與優勢
-
04.跨進程組件通信
- 4.1 URLScheme
- 4.2 AIDL
- 4.3 BroadcastReceiver
- 4.4 路由通信注意要點
- 05.ARouter的結構
-
06.ARouter的工作流程
- 6.1 初始化流程
- 6.2 跳轉頁面流程
-
07.ARouter簡單調用api
- 7.1 最簡單調用
- 7.2 build源碼分析
- 7.3 navigation分析
- 08.Postcard信息攜帶
- 09.LogisticsCenter
- 10.DegradeService降級容錯服務
- 11.Interceptor攔截器
- 12.數據傳輸和自動注入
- 13.多dex的支持
- 14.InstantRun支持
- 15.生成的編譯代碼
好消息
- 博客筆記大彙總【16年3月到至今】,包括Java基礎及深入知識點,Android技術博客,Python學習筆記等等,還包括平時開發中遇到的bug彙總,當然也在工作之餘收集了大量的面試題,長期更新維護並且修正,持續完善……開源的文件是markdown格式的!同時也開源了生活博客,從12年起,積累共計N篇[近100萬字,陸續搬到網上],轉載請註明出處,謝謝!
- 鏈接地址:https://github.com/yangchong2...
- 如果覺得好,可以star一下,謝謝!當然也歡迎提出建議或者問題,萬事起於忽微,量變引起質變!
註解學習小案例
- 註解學習小案例,比較系統性學習註解並且應用實踐。簡單應用了運行期註解,通過註解實現了setContentView功能;簡單應用了編譯器註解,通過註解實現了防暴力點擊的功能,同時支持設置時間間隔;使用註解替代枚舉;使用註解一步步搭建簡單路由案例。結合相應的博客,在來一些小案例,從此應該對註解有更加深入的理解……
- 開源項目地址:https://github.com/yangchong2...
01.原生跳轉實現
- Google提供的原聲路由主要是通過intent,可以分成顯示和隱式兩種。顯示的方案會導致類之間的直接依賴問題,耦合嚴重;隱式intent需要的配置清單中統一聲明,首先有個暴露的問題,另外在多模塊開發中協作也比較困難。只要調用startActivity後面的環節我們就無法控制了,在出現錯誤時無能爲力。
02.實現組件跳轉方式
2.1 傳統跳轉方式
- 第一種,通過intent跳轉
- 第二種,通過aidl跳轉
- 第三種,通過scheme協議跳轉
2.2 爲何需要路由
- 顯示Intent:項目龐大以後,類依賴耦合太大,不適合組件化拆分
- 隱式Intent:協作困難,調用時候不知道調什麼參數
- 每個註冊了Scheme的Activity都可以直接打開,有安全風險
- AndroidMainfest集中式管理比較臃腫
- 無法動態修改路由,如果頁面出錯,無法動態降級
- 無法動態攔截跳轉,譬如未登錄的情況下,打開登錄頁面,登錄成功後接着打開剛纔想打開的頁面
- H5、Android、iOS地址不一樣,不利於統一跳轉
03.ARouter配置與優勢
3.1 ARouter的優勢
-
如下所示
- 直接解析URL路由,解析參數並賦值
- 支持多模塊項目
- 支持InstantRun
- 允許自定義攔截器
- ARouter可以提供IoC容器
- 映射關係自動註冊
- 靈活的降級策略
3.2 至於配置和使用
04.跨進程組件通信
4.1 URLScheme【例如:ActivityRouter、ARouter等】
-
優勢有:
- 基因中自帶支持從webview中調用
- 不用互相註冊(不用知道需要調用的app的進程名稱等信息)
-
劣勢有:
- 只能單向地給組件發送信息,適用於啓動Activity和發送指令,不適用於獲取數據(例如:獲取用戶組件的當前用戶登錄信息)
- 需要有個額外的中轉Activity來統一處理URLScheme
- 如果設備上安裝了多個使用相同URLScheme的app,會彈出選擇框(多個組件作爲app同時安裝到設備上時會出現這個問題)
- 無法進行權限設置,無法進行開關設置,存在安全性風險
4.2 AIDL
-
優勢有:
- 可以傳遞Parcelable類型的對象
- 效率高
- 可以設置跨app調用的開關
-
劣勢有:
- 調用組件之前需要提前知道該組件在那個進程,否則無法建立ServiceConnection
- 組件在作爲獨立app和作爲lib打包到主app時,進程名稱不同,維護成本高
4.3 BroadcastReceiver
- BroadcastReceiver + Service + LocalSocket。該方案是參考cc路由框架!
-
跨組件間通信實現的同時,應該滿足以下條件:
- 每個app都能給其它app調用
- app可以設置是否對外提供跨進程組件調用的支持
- 組件調用的請求發出去之後,能自動探測當前設備上是否有支持此次調用的app
- 支持超時、取消
4.4 路由通信注意要點
05.ARouter的結構
-
ARouter主要由三部分組成,包括對外提供的api調用模塊、註解模塊以及編譯時通過註解生產相關的類模塊。
- arouter-annotation註解的聲明和信息存儲類的模塊
- arouter-compiler編譯期解析註解信息並生成相應類以便進行注入的模塊
- arouter-api核心調用Api功能的模塊
-
annotation模塊
- Route、Interceptor、Autowired都是在開發是需要的註解。
-
compiler模塊
- AutoWiredProcessor、InterceptorProcessor、RouteProcessor分別爲annotation模塊對應的Autowired、Interceptor、Route在項目編譯時產生相關的類文件。
-
api模塊
- 主要是ARouter具體實現和對外暴露使用的api。
06.ARouter的工作流程
6.1 初始化流程
-
初始化代碼如下所示
/**
*/
public static void init(Application application) {
//如果沒有初始化,則
if (!hasInit) {
logger = _ARouter.logger;
_ARouter.logger.info(Consts.TAG, "ARouter init start.");
//做初始化工作
hasInit = _ARouter.init(application);
if (hasInit) {
_ARouter.afterInit();
}
_ARouter.logger.info(Consts.TAG, "ARouter init over.");
}
}
```
-
之後接着看_ARouter.init(application)這行代碼,點擊去查看
protected static synchronized boolean init(Application application) { //賦值上下文 mContext = application; //初始化LogisticsCenter LogisticsCenter.init(mContext, executor); logger.info(Consts.TAG, "ARouter init success!"); hasInit = true; mHandler = new Handler(Looper.getMainLooper()); return true; }
-
接下來看看LogisticsCenter裏面做了什麼
public class LogisticsCenter { /**
*/
public synchronized static void init(Context context, ThreadPoolExecutor tpe) throws HandlerException {
mContext = context;
executor = tpe;
try {
long startInit = System.currentTimeMillis();
Set<String> routerMap;
//debug或者版本更新的時候每次都重新加載router信息
// It will rebuild router map every times when debuggable.
if (ARouter.debuggable() || PackageUtils.isNewVersion(context)) {
logger.info(TAG, "Run with debug mode or new install, rebuild router map.");
// These class was generate by arouter-compiler.
//加載alibaba.android.arouter.routes包下載的類
routerMap = ClassUtils.getFileNameByPackageName(mContext, ROUTE_ROOT_PAKCAGE);
if (!routerMap.isEmpty()) {
context.getSharedPreferences(AROUTER_SP_CACHE_KEY, Context.MODE_PRIVATE).edit().putStringSet(AROUTER_SP_KEY_MAP, routerMap).apply();
}
PackageUtils.updateVersion(context); // Save new version name when router map update finish.
} else {
logger.info(TAG, "Load router map from cache.");
routerMap = new HashSet<>(context.getSharedPreferences(AROUTER_SP_CACHE_KEY, Context.MODE_PRIVATE).getStringSet(AROUTER_SP_KEY_MAP, new HashSet<String>()));
}
logger.info(TAG, "Find router map finished, map size = " + routerMap.size() + ", cost " + (System.currentTimeMillis() - startInit) + " ms.");
startInit = System.currentTimeMillis();
for (String className : routerMap) {
if (className.startsWith(ROUTE_ROOT_PAKCAGE + DOT + SDK_NAME + SEPARATOR + SUFFIX_ROOT)) {
// This one of root elements, load root.
//導入ARouter$$Root$$app.java,初始化Warehouse.groupsIndex集合
((IRouteRoot) (Class.forName(className).getConstructor().newInstance())).loadInto(Warehouse.groupsIndex);
} else if (className.startsWith(ROUTE_ROOT_PAKCAGE + DOT + SDK_NAME + SEPARATOR + SUFFIX_INTERCEPTORS)) {
// Load interceptorMeta
//導入ARouter$$Interceptors$$app.java,初始化Warehouse.interceptorsIndex集合
((IInterceptorGroup) (Class.forName(className).getConstructor().newInstance())).loadInto(Warehouse.interceptorsIndex);
} else if (className.startsWith(ROUTE_ROOT_PAKCAGE + DOT + SDK_NAME + SEPARATOR + SUFFIX_PROVIDERS)) {
// Load providerIndex
//導入ARouter$$Providers$$app.java,初始化Warehouse.providersIndex集合
((IProviderGroup) (Class.forName(className).getConstructor().newInstance())).loadInto(Warehouse.providersIndex);
}
}
/*******部分代碼省略********/
} catch (Exception e) {
throw new HandlerException(TAG + "ARouter init logistics center exception! [" + e.getMessage() + "]");
}
}
}
```
-
綜上所述,整個初始化的流程大概就是:
- 初始化運行時的上下文環境
- 初始化日誌logger
- 尋找router相關的類
- 解析並且緩存路由相關信息
- 初始化攔截服務
6.2 跳轉頁面流程
07.ARouter調用api
7.1 最簡單調用
-
最簡單的調用方式
ARouter.getInstance() .build("/user/UserFragment") .navigation();
7.2 build源碼分析
-
這個主要是添加跳轉的路徑
public Postcard build(String path) { return _ARouter.getInstance().build(path); }
-
然後把這個路徑添加到默認的組中
/**
*/
protected Postcard build(String path) {
if (TextUtils.isEmpty(path)) {
throw new HandlerException(Consts.TAG + "Parameter is invalid!");
} else {
PathReplaceService pService = ARouter.getInstance().navigation(PathReplaceService.class);
if (null != pService) {
path = pService.forString(path);
}
return build(path, extractGroup(path));
}
}
```
7.3 navigation分析
-
如下所示
final class _ARouter { protected Object navigation(final Context context, final Postcard postcard, final int requestCode, final NavigationCallback callback) { try { LogisticsCenter.completion(postcard); } catch (NoRouteFoundException ex) { /**************部分代碼省略***************/ if (null != callback) { callback.onLost(postcard); } else { // No callback for this invoke, then we use the global degrade service. DegradeService degradeService = ARouter.getInstance().navigation(DegradeService.class); if (null != degradeService) { degradeService.onLost(context, postcard); } } return null; } if (null != callback) { callback.onFound(postcard); } //是否爲綠色通道,是否進過攔截器處理 if (!postcard.isGreenChannel()) { // It must be run in async thread, maybe interceptor cost too mush time made ANR. interceptorService.doInterceptions(postcard, new InterceptorCallback() { @Override public void onContinue(Postcard postcard) { _navigation(context, postcard, requestCode, callback); } @Override public void onInterrupt(Throwable exception) { //中斷處理 if (null != callback) { callback.onInterrupt(postcard); } } }); } else { return _navigation(context, postcard, requestCode, callback); } return null; } private Object _navigation(final Context context, final Postcard postcard, final int requestCode, final NavigationCallback callback) { //沒有上下文環境,就用Application的上下文環境 final Context currentContext = null == context ? mContext : context; switch (postcard.getType()) { case ACTIVITY: // Build intent 構建跳轉的intent final Intent intent = new Intent(currentContext, postcard.getDestination()); intent.putExtras(postcard.getExtras()); // Set flags. 設置flag int flags = postcard.getFlags(); if (-1 != flags) { intent.setFlags(flags); } else if (!(currentContext instanceof Activity)) { // Non activity, need less one flag. //如果上下文不是Activity,則添加FLAG_ACTIVITY_NEW_TASK的flag intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); } // Navigation in main looper. 切換到主線程中 new Handler(Looper.getMainLooper()).post(new Runnable() { @Override public void run() { if (requestCode > 0) { // Need start for result ActivityCompat.startActivityForResult((Activity) currentContext, intent, requestCode, postcard.getOptionsBundle()); } else { ActivityCompat.startActivity(currentContext, intent, postcard.getOptionsBundle()); } if ((0 != postcard.getEnterAnim() || 0 != postcard.getExitAnim()) && currentContext instanceof Activity) { // Old version. ((Activity) currentContext).overridePendingTransition(postcard.getEnterAnim(), postcard.getExitAnim()); } if (null != callback) { // Navigation over. callback.onArrival(postcard); } } }); break; case PROVIDER: return postcard.getProvider(); case BOARDCAST: case CONTENT_PROVIDER: case FRAGMENT: Class fragmentMeta = postcard.getDestination(); try { Object instance = fragmentMeta.getConstructor().newInstance(); if (instance instanceof Fragment) { ((Fragment) instance).setArguments(postcard.getExtras()); } else if (instance instanceof android.support.v4.app.Fragment) { ((android.support.v4.app.Fragment) instance).setArguments(postcard.getExtras()); } return instance; } catch (Exception ex) { logger.error(Consts.TAG, "Fetch fragment instance error, " + TextUtils.formatStackTrace(ex.getStackTrace())); } case METHOD: case SERVICE: default: return null; } return null; } }
08.Postcard信息攜帶
- Postcard主要爲信息的攜帶者,內容是在構造一次路由信息的時候生產的,其繼承於RouteMeta。RouteMeta是在代碼編譯時生成的內容,主要在初始化WareHouse時對跳轉信息做了緩存。
-
看看代碼如下所示
//Postcard繼承於RouteMeta public final class Postcard extends RouteMeta //然後看看編譯生成的文件 /**
public class ARouter$$Group$$me implements IRouteGroup {
@Override
public void loadInto(Map<String, RouteMeta> atlas) {
atlas.put("/me/ExperienceCouponActivity", RouteMeta.build(RouteType.ACTIVITY, ExperienceCouponActivity.class, "/me/experiencecouponactivity", "me", null, -1, -2147483648));
atlas.put("/me/ServiceActivity", RouteMeta.build(RouteType.ACTIVITY, ServiceActivity.class, "/me/serviceactivity", "me", null, -1, -2147483648));
atlas.put("/me/SettingActivity", RouteMeta.build(RouteType.ACTIVITY, SettingActivity.class, "/me/settingactivity", "me", null, -1, -2147483648));
atlas.put("/me/UdeskServiceActivity", RouteMeta.build(RouteType.ACTIVITY, UdeskServiceActivity.class, "/me/udeskserviceactivity", "me", null, -1, -2147483648));
}
}
```
10.DegradeService降級容錯服務
-
首先,自定義一個類,需要繼承DegradeService類,如下所示
/** * <pre> * @author 楊充 * blog : https://github.com/yangchong211 * time : 2018/08/24 * desc : ARouter路由降級處理 * revise:
*/
@Route(path = DegradeServiceImpl.PATH)
public class DegradeServiceImpl implements DegradeService {
static final String PATH = "/service/DegradeServiceImpl";
@Override
public void onLost(Context context, Postcard postcard) {
if (context != null && postcard.getGroup().equals("activity")) {
Intent intent = new Intent(context, WebViewActivity.class);
intent.putExtra(Constant.URL, Constant.GITHUB);
intent.putExtra(Constant.TITLE, "github地址");
ActivityCompat.startActivity(context, intent, null);
}
}
@Override
public void init(Context context) {
}
}
```
-
如何使用該降級方案,十分簡單。
NavigationCallback callback = new NavCallback() { @Override public void onArrival(Postcard postcard) { LogUtils.i("ARouterUtils"+"---跳轉完了"); } @Override public void onFound(Postcard postcard) { super.onFound(postcard); LogUtils.i("ARouterUtils"+"---找到了"); } @Override public void onInterrupt(Postcard postcard) { super.onInterrupt(postcard); LogUtils.i("ARouterUtils"+"---被攔截了"); } @Override public void onLost(Postcard postcard) { super.onLost(postcard); LogUtils.i("ARouterUtils"+"---找不到了"); DegradeServiceImpl degradeService = new DegradeServiceImpl(); degradeService.onLost(Utils.getApp(),postcard); } };
11.Interceptor攔截器
-
在ARouter模塊的時候講述Interceptor的使用,如果本次路由跳轉不是走的綠色通道那麼則會觸發攔截器進行過濾。
final class _ARouter { protected Object navigation(final Context context, final Postcard postcard, final int requestCode, final NavigationCallback callback) { /************部分代碼省略************/ if (!postcard.isGreenChannel()) { // It must be run in async thread, maybe interceptor cost too mush time made ANR. interceptorService.doInterceptions(postcard, new InterceptorCallback() { /**
*
* @param postcard route meta
*/
@Override
public void onContinue(Postcard postcard) {
_navigation(context, postcard, requestCode, callback);
}
/**
* Interrupt process, pipeline will be destory when this method called.
*
* @param exception Reson of interrupt.
*/
@Override
public void onInterrupt(Throwable exception) {
if (null != callback) {
callback.onInterrupt(postcard);
}
logger.info(Consts.TAG, "Navigation failed, termination by interceptor : " + exception.getMessage());
}
});
} else {
return _navigation(context, postcard, requestCode, callback);
}
return null;
}
}
```
-
攔截器的初始化
- 在剛開始初始化的時候,就已經做了這個操作。
final class _ARouter { static void afterInit() { // Trigger interceptor init, use byName. interceptorService = (InterceptorService) ARouter.getInstance().build("/arouter/service/interceptor").navigation(); } }
-
InterceptorServiceImpl的init方法:
@Route(path = "/arouter/service/interceptor") public class InterceptorServiceImpl implements InterceptorService { @Override public void init(final Context context) { LogisticsCenter.executor.execute(new Runnable() { @Override public void run() { if (MapUtils.isNotEmpty(Warehouse.interceptorsIndex)) { //循環遍歷倉庫中的攔截器 for (Map.Entry<Integer, Class<? extends IInterceptor>> entry : Warehouse.interceptorsIndex.entrySet()) { Class<? extends IInterceptor> interceptorClass = entry.getValue(); try { //反射機制構造自定義的每一個攔截器實例 IInterceptor iInterceptor = interceptorClass.getConstructor().newInstance(); iInterceptor.init(context); //並將其添加在緩存中 Warehouse.interceptors.add(iInterceptor); } catch (Exception ex) { throw new HandlerException(TAG + "ARouter init interceptor error! name = [" + interceptorClass.getName() + "], reason = [" + ex.getMessage() + "]"); } } interceptorHasInit = true; logger.info(TAG, "ARouter interceptors init over."); synchronized (interceptorInitLock) { interceptorInitLock.notifyAll(); } } } }); } }
-
攔截器的工作過程
@Route(path = "/arouter/service/interceptor") public class InterceptorServiceImpl implements InterceptorService { @Override public void doInterceptions(final Postcard postcard, final InterceptorCallback callback) { if (null != Warehouse.interceptors && Warehouse.interceptors.size() > 0) { //檢測是否初始化完所有的爛機器 checkInterceptorsInitStatus(); //沒有完成正常的初始化,拋異常 if (!interceptorHasInit) { callback.onInterrupt(new HandlerException("Interceptors initialization takes too much time.")); return; } //順序遍歷每一個攔截器, LogisticsCenter.executor.execute(new Runnable() { @Override public void run() { CancelableCountDownLatch interceptorCounter = new CancelableCountDownLatch(Warehouse.interceptors.size()); try { _excute(0, interceptorCounter, postcard); interceptorCounter.await(postcard.getTimeout(), TimeUnit.SECONDS); //攔截器的遍歷終止之後,如果有還有沒有遍歷的攔截器,則表示路由事件被攔截 if (interceptorCounter.getCount() > 0) { // Cancel the navigation this time, if it hasn't return anythings. callback.onInterrupt(new HandlerException("The interceptor processing timed out.")); } else if (null != postcard.getTag()) { // Maybe some exception in the tag. callback.onInterrupt(new HandlerException(postcard.getTag().toString())); } else { callback.onContinue(postcard); } } catch (Exception e) { callback.onInterrupt(e); } } }); } else { callback.onContinue(postcard); } } //執行攔截器的過濾事件 private static void _excute(final int index, final CancelableCountDownLatch counter, final Postcard postcard) { if (index < Warehouse.interceptors.size()) { IInterceptor iInterceptor = Warehouse.interceptors.get(index); iInterceptor.process(postcard, new InterceptorCallback() { @Override public void onContinue(Postcard postcard) { // Last interceptor excute over with no exception. counter.countDown(); //如果當前沒有攔截過濾,那麼使用下一個攔截器 _excute(index + 1, counter, postcard); // When counter is down, it will be execute continue ,but index bigger than interceptors size, then U know. } @Override public void onInterrupt(Throwable exception) { // Last interceptor excute over with fatal exception. postcard.setTag(null == exception ? new HandlerException("No message.") : exception.getMessage()); // save the exception message for backup. counter.cancel(); } }); } } }
12.數據傳輸和自動注入
13.多dex的支持
-
可查看multidex源碼:
public class ClassUtils { /** * Identifies if the current VM has a native support for multidex, meaning there is no need for
*
* @return true if the VM handles multidex
*/
private static boolean isVMMultidexCapable() {
boolean isMultidexCapable = false;
String vmName = null;
try {
if (isYunOS()) { // YunOS需要特殊判斷
vmName = "'YunOS'";
isMultidexCapable = Integer.valueOf(System.getProperty("ro.build.version.sdk")) >= 21;
} else { // 非YunOS原生Android
vmName = "'Android'";
String versionString = System.getProperty("java.vm.version");
if (versionString != null) {
Matcher matcher = Pattern.compile("(\\d+)\\.(\\d+)(\\.\\d+)?").matcher(versionString);
if (matcher.matches()) {
try {
int major = Integer.parseInt(matcher.group(1));
int minor = Integer.parseInt(matcher.group(2));
isMultidexCapable = (major > VM_WITH_MULTIDEX_VERSION_MAJOR)
|| ((major == VM_WITH_MULTIDEX_VERSION_MAJOR)
&& (minor >= VM_WITH_MULTIDEX_VERSION_MINOR));
} catch (NumberFormatException ignore) {
// let isMultidexCapable be false
}
}
}
}
} catch (Exception ignore) {
}
Log.i(Consts.TAG, "VM with name " + vmName + (isMultidexCapable ? " has multidex support" : " does not have multidex support"));
return isMultidexCapable;
}
}
```
14.InstantRun支持
-
什麼是InstantRun支持?
- Android Studio 2.0 中引入的 Instant Run 是 Run 和 Debug 命令的行爲,可以大幅縮短應用更新的時間。儘管首次構建可能需要花費較長的時間,Instant Run 在嚮應用推送後續更新時則無需構建新的 APK,因此,這樣可以更快地看到更改。
15.生成的編譯代碼
-
如下所示
關於其他內容介紹
01.關於博客彙總鏈接
02.關於我的博客
- 我的個人站點:www.yczbj.org,www.ycbjie.cn
- github:https://github.com/yangchong211
- 知乎:https://www.zhihu.com/people/...
- 簡書:http://www.jianshu.com/u/b7b2...
- csdn:http://my.csdn.net/m0_37700275
- 喜馬拉雅聽書:http://www.ximalaya.com/zhubo...
- 開源中國:https://my.oschina.net/zbj161...
- 泡在網上的日子:http://www.jcodecraeer.com/me...
- 郵箱:[email protected]
- 阿里雲博客:https://yq.aliyun.com/users/a... 239.headeruserinfo.3.dT4bcV
- segmentfault頭條:https://segmentfault.com/u/xi...
- 掘金:https://juejin.im/user/593943...