I am launching activities from the main activity in my app using the call startActivityForResult(intent, ACTIVITY_TYPE)
, and they are all working but one.
This one, when called, launches the activity as desired, but in the log I can see that onActivityResult()
is immediately being triggered. The activity shows up but RESULT_CANCELED
is immediately returned to onActivityResult()
.
I then interact with the activity, press a button which calls finish()
, and onActivityResult()
is not called this time (because apparently a result has already been returned).
Does this make sense to anyone? Has anyone seen this behavior before?
You can't use startActivityForResult()
if your activity is being launched as a singleInstance
or singleTask
. standard
or singleTop
launch mode will fix the problem.
Additionally make sure the intent does not have the Intent.FLAG_ACTIVITY_NEW_TASK
set.
From the docs :
This flag can not be used when the caller is requesting a result from the activity being launched.
I have seen this behavior before, please make sure your destnation activity (that special activity) is not singleInstance
in AndroidManifest file. If the Activity is singleInstance
, then it will return RESULT_CANCELED
before launched!
I'd also like to add that you could call an external app with:
Intent in = caller.getPackageManager().getLaunchIntentForPackage("com.your.package.here");
Which would create an intent with Intent.FLAG_ACTIVITY_NEW_TASK
added by default, so call:
in.setFlags(0);
Which will clear that flag, and then you can proceed to: startActivityForResult(in, action);
Reason I'm doing this is that I have a utility app that has common functionality between a few other apps and I can keep the code changes to one location instead of worrying about multiple updates.
startActivityForResult()
doesn't work with a singleInstance
or singleTask
activity in pre-lollipop version of Android. Since Android 5 it works (see this answer for more details).
It also triggers if you have FLAG_ACTIVITY_NEW_TASK
in your intent.
Intent intent = new Intent(this, MyActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivityForResult(intent, REQUEST_CODE);
My problem was with the calling activity. Its declaration in the AndroidManifest had the following property:
android:noHistory="true"
Changed it to "false" and now works fine.
Android 4.4 has a small problem about waiting for the return at the end of the actvity closure To solve this behavior it is important to set :
TaskAffinity = "[SAME STRING]"
) launchmode=singleTop,
launchIntent.SetFlags(0); // for reset default Intent flags if you launch from package manager
This solution works with all version of Android
See this for taskAffinity: https://asyoulook.com/computers%20&%20internet/android-onactivityresult-being-called-instantly/1004072
另外,检查清单中的活动是否 android:noHistory="true" ,如果是,它将不起作用。
For ActivityGroup
or TabHost
and others, maybe the xxxActivity
is a subActivity
of its parent. Then the startActivityForResult
can not work but the parent can get the result.
call getParent().startActivityForResult()
from your sub-activity
your parent (the ActivityGroup
) will be able to handle the onActivityResult
. So I created a subclass of ActivityGroup
and handled this onActivityResult
.
You can re-route that result back to the sub-activity if you need to. Just get the current activity by getLocalActivityManager().getCurrentActivity()
. My sub-activities inherit from a custom activity so I added a handleActivityResult(requestCode, resultCode, data)
in that subclass for the ActivityGroup
to call.
example: http://www.cnblogs.com/relinson/archive/2012/03/25/startActivityForResult.html
如果您在清单文件中拼错了包或类名, onActivityResult()
也会将RESULT_CANCELED
作为resultCode
传递。
在 Android Manifest 中,为您想要打开的活动设置android:launchMode="singleTop"
并在打开活动时设置标志intent.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);
如果您在 AndroidManifest.xml 的 Activity 中定义了android:noHistory="true"
,则会在此处导致相同的问题。
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