taskAffinity 和 FLAG_ACTIVITY_NEW_TASK都是和activity启动时是否需要新建一个task有关,我们分四种情况看一下这两个标志对启动activity的影响:(前提:从MainActivity中启动ActivityA)
1)、两个标志都不设置
2)、有FLAG_ACTIVITY_NEW_TASK
3)、无FLAG_ACTIVITY_NEW_TASK有taskAffinity (不同于MainActivity)
4)、有FLAG_ACTIVITY_NEW_TASK有taskAffinity
注意上面的标志都是针对于启动的ActivityA,FLAG_ACTIVITY_NEW_TASK 是在启动ActivityA的Intent中设置的,taskAffinity 是在AndroidManifest中ActivityA中设置,另外注意这里两个actiity的启动模式都设置为standard
1、先看第一中情况:
主要代码:
2、有FLAG_ACTIVITY_NEW_TASK
我们添加FLAG_ACTIVITY_NEW_TASK
public void onClick(View arg0) { // TODO Auto-generated method stub Log.i(TAG, "--onClick--task id = " + getCurrentTaskId()); Intent intent = new Intent("com.leaves.ipanel.ActivityA"); intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); startActivity(intent); }
ACTIVITY MANAGER ACTIVITIES (dumpsys activity activities) Main stack: TaskRecord{415ebce8 #37 A com.leaves.ipanel U 0} Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=com.leaves.ipanel/.MainActivity } Hist #2: ActivityRecord{42358368 u0 com.leaves.ipanel/.ActivityA} Intent { act=com.leaves.ipanel.ActivityA cmp=com.leaves.ipanel/.ActivityA } ProcessRecord{42384ad8 7591:com.leaves.ipanel/u0a10061} Hist #1: ActivityRecord{4132a3d0 u0 com.leaves.ipanel/.MainActivity} Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=com.leaves.ipanel/.MainActivity } ProcessRecord{42384ad8 7591:com.leaves.ipanel/u0a10061} TaskRecord{41350f60 #2 A com.android.launcher U 0} Intent { act=android.intent.action.MAIN cat=[android.intent.category.HOME] flg=0x10000000 cmp=com.android.launcher/com.android.launcher2.Launcher } Hist #0: ActivityRecord{41616790 u0 com.android.launcher/com.android.launcher2.Launcher} Intent { act=android.intent.action.MAIN cat=[android.intent.category.HOME] flg=0x10000000 cmp=com.android.launcher/com.android.launcher2.Launcher } ProcessRecord{41615818 628:com.android.launcher/1000}
可见,跟启动他的activity还是同属于一个task.
3、无FLAG_ACTIVITY_NEW_TASK有taskAffinity (不同于MainActivity)
<activity android:name=".ActivityA" android:launchMode="standard" android:taskAffinity="com.leaves.test.ActivityA" android:label="@string/title_activityA"> <intent-filter> <action android:name="com.leaves.ipanel.ActivityA"/> <category android:name="android.intent.category.DEFAULT"/> </intent-filter> </activity>
查看一下启动A之后的堆栈:
ACTIVITY MANAGER ACTIVITIES (dumpsys activity activities) Main stack: TaskRecord{415ebce8 #37 A com.leaves.ipanel U 0} Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=com.leaves.ipanel/.MainActivity } Hist #2: ActivityRecord{42358368 u0 com.leaves.ipanel/.ActivityA} Intent { act=com.leaves.ipanel.ActivityA cmp=com.leaves.ipanel/.ActivityA } ProcessRecord{42384ad8 7591:com.leaves.ipanel/u0a10061} Hist #1: ActivityRecord{4132a3d0 u0 com.leaves.ipanel/.MainActivity} Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] flg=0x10000000 cmp=com.leaves.ipanel/.MainActivity } ProcessRecord{42384ad8 7591:com.leaves.ipanel/u0a10061} TaskRecord{41350f60 #2 A com.android.launcher U 0} Intent { act=android.intent.action.MAIN cat=[android.intent.category.HOME] flg=0x10000000 cmp=com.android.launcher/com.android.launcher2.Launcher } Hist #0: ActivityRecord{41616790 u0 com.android.launcher/com.android.launcher2.Launcher} Intent { act=android.intent.action.MAIN cat=[android.intent.category.HOME] flg=0x10000000 cmp=com.android.launcher/com.android.launcher2.Launcher } ProcessRecord{41615818 628:com.android.launcher/1000}
跟前面两种情况是一样的。
4、有FLAG_ACTIVITY_NEW_TASK有taskAffinity
把FLAG_ACTIVITY_NEW_TASK添加上去
上面我们测试的两个Activity是在同一个应用中,如果他们在不同的应用中呢,例如ActivityA跟MainActivity不在一个apk中,其实情况还是一样的,只是这个时候,如果没有在AndroidManifest.xml中设置taskAffinity,则他们两个的taskAffinity是不一样的。因为默认如果没有设置taskAffinity,则taskAffinity跟包名是一样的,所以,如果ActivityA跟MainActivity不在一个apk中,当没有FLAG_ACTIVITY_NEW_TASK时,则两者应该是在同一个task,但是如果有FLAG_ACTIVITY_NEW_TASK,则两者应该会在不同的task中。
总结:
如果没有设置FLAG_ACTIVITY_NEW_TASK,且是从一个activity中启动另一个activity,即sourceRecord不为null,则设置新启动的TaskRecord为即sourceRecord的TaskRecord
如果设置了FLAG_ACTIVITY_NEW_TASK,则根据task的 affinity、intent、ComponentName等查找是否有合适的TaskRecord