…
return startActivity(r, sourceRecord, voiceSession, voiceInteractor, startFlags, true /* doResume */, checkedOptions, inTask, outActivity);
}
但是 intent.getComponent()，aInfo又是从哪儿获取的呢，我们回溯到
startActivityMayWait.
看下上面的aInfo哪来的.
ActivityInfo resolveActivity(Intent intent, ResolveInfo rInfo, int startFlags, ProfilerInfo profilerInfo) {
final ActivityInfo aInfo = rInfo != null ? rInfo.activityInfo : null;
if (aInfo != null) {
// Store the found target back into the intent, because now that
// we have it we never want to do this again. For example, if the
// user navigates back to this point in the history, we should
// always restart the exact same activity.
intent.setComponent(new ComponentName(aInfo.applicationInfo.packageName, aInfo.name));
// Don’t debug things in the system process …
}
return aInfo;
}
发现是从rInfo来的
ResolveInfo resolveIntent(Intent intent, String resolvedType, int userId, int flags, int filterCallingUid) {
synchronized (mService) {
try {…final long token = Binder.clearCallingIdentity();
try {
return mService.getPackageManagerInternalLocked().resolveIntent(intent, resolvedType, modifiedFlags, userId, true, filterCallingUid);
} finally {
Binder.restoreCallingIdentity(token);
} …
}
}
}
rInfo的获取
PackageManagerInternal getPackageManagerInternalLocked() {
if (mPackageManagerInt == null) {
mPackageManagerInt = LocalServices.getService(PackageManagerInternal.class);
}
return mPackageManagerInt;
}
具体实现类是PackageManagerService
@Override
public ResolveInfo resolveIntent(Intent intent, String resolvedType, int flags, int userId) {
return resolveIntentInternal(intent, resolvedType, flags, userId, false, Binder.getCallingUid());
}
看resolveIntentInternal
private ResolveInfo resolveIntentInternal(Intent intent, String resolvedType,int flags, int userId, boolean resolveForStart, int filterCallingUid) {
try {…
//获取ResolveInfo列表
final List query = queryIntentActivitiesInternal(intent, resolvedType, flags, filterCallingUid, userId, resolveForStart, true /allowDynamicSplits/);
Trace.traceEnd(TRACE_TAG_PACKAGE_MANAGER);
//找出最好的返回
final ResolveInfo bestChoice = chooseBestActivity(intent, resolvedType, flags, query, userId);
return bestChoice;
} finally {
Trace.traceEnd(TRACE_TAG_PACKAGE_MANAGER);
}
}
看 queryIntentActivitiesInternal
private @NonNull List queryIntentActivitiesInternal(Intent intent, String resolvedType, int flags, int filterCallingUid, int userId, boolean resolveForStart, boolean allowDynamicSplits) {
…
if (comp != null) {
final List list = new ArrayList(1);
final ActivityInfo ai = getActivityInfo(comp, flags, userId);
if (ai != null) {
…
}
}
原来是从getActivityInfo获取的
@Override
public ActivityInfo getActivityInfo(ComponentName component, int flags, int userId) {
return getActivityInfoInternal(component, flags, Binder.getCallingUid(), userId);
}
getActivityInfoInternal方法
private ActivityInfo getActivityInfoInternal(ComponentName component, int flags, int filterCallingUid, int userId) {
if (!sUserManager.exists(userId)) return null;
flags = updateFlagsForComponent(flags, userId, component);
if (!isRecentsAccessingChildProfiles(Binder.getCallingUid(), userId)) {
mPermissionManager.enforceCrossUserPermission(Binder.getCallingUid(), userId, false /* requireFullPermission /, false / checkShell */, “get activity info”);
}
synchronized (mPackages) {
//关键点
PackageParser.Activity a = mActivities.mActivities.get(component);
if (DEBUG_PACKAGE_INFO) Log.v(TAG, "getActivityInfo " + component + ": " + a);
if (a != null && mSettings.isEnabledAndMatchLPr(a.info, flags, userId)) {
PackageSetting ps = mSettings.mPackages.get(component.getPackageName());
if (ps == null) return null;
if (filterAppAccessLPr(ps, filterCallingUid, component, TYPE_ACTIVITY, userId)) {
return null;
}
//关键点
return PackageParser.generateActivityInfo(a, flags, ps.readUserState(userId), userId);
}
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[外链图片转存中…(img-pnk2QBki-1645097719069)]
