In activity manifest file i have marked it as android:noHistory="true" because I did not want the screen to be added to the activity stack.
when I lock the screen and unlock it. The activity disappears and the previous screen appears. This should not happen. Please any one can suggest me, how can i handle this on ICS devices. However its working fine on Gingerbread devices.
Remove android:noHistory="true" in android manifest file and call the finish when you move out of that Activity. This will remove the activity completely from the stack and it will not be displayed in your backstack. I hope this will work for you
Related
Will be obliged if someone can help me with this.We were working on some android application,while designing its prototype we came across some issues.A little description of the application's prototype is as follows:
A Log in screen
a Home screen with logout at its top right
Every other activity is having a home button on top right corner.
Now going from one activity to the other in my application, I just called finished on the current activity and started the other(so there is no stack of the activities is being created) and when home button present on each activity's top corner is pressed i finish the current activity and move to the home screen.
More precisely,i can say that i am overriding every activty's onBackPressed() method
.By doing this i am not letting android to keep a stack of the activity's but by doing this I have a feeling that, I am loosing efficiency and degrading performance.Because on every backpress or home button click one activity is finished and the other is created.Hence some lag can be seen as the acivity is recreated.
Please suggest that should I continue WITH THIS or there is some other way out to handle this
Thank you for Giving your time
It is depends.
If you are giving option on each screen to to go home this approach is good.
Because if you are keep activities in stack it will be in RAM which is limited so it may create memory issue if to many activities in stack.
I would like to suggest one more thing.
As you say you have overridden onBackPressed() method in each activity.
Rather doing this there is a option you can specify parent activity in manifest tag.
So you no need to manually handle by overriding onBackPressed() method.
EG.
<activity
android:name="com.xxx.DetailActivity"
android:parentActivityName="com.xxx.src.ListActivity"
android:screenOrientation="portrait"
android:theme="#android:style/Theme.Translucent.NoTitleBar.Fullscreen" />
My app is built with the support ActionBar to allow for a standard UI between Android 4.x and Android 2.3, and for the most part this works fine. However, the title is not displayed in the ActionBar when I first launch the app under Android 2.3.
If I rotate the device to landscape mode, then the title appears in the ActionBar. After rotating the device back to portrait mode, the title is still visible.
What could be causing this? When I launch a different Activity in the app, that Activity's label (as specified in AndroidManifest.xml) is correctly displayed in the ActionBar.
EDIT: I've tracked this down to a splash screen Activity that is launched from the main activity's onCreate method. I can probably work around this be rearchitecting the app to launch with the splash screen as its default launch activity and then launch the main activity, but are there any other workarounds?
Unfortunately, I don't think "remove the splash screen" will be acceptable.
As far as I can tell, this issue is a bug in Android 2.3. It seems like this problem was caused by my launch Activity starting another Activity (the splash screen) from its onCreate method. Moving the splash screen launch to onStart or onResume did not help to resolve this issue.
I was able to work around the issue by replacing the internals of my launch Activity with the splash screen and creating a new "real main Activity" that the splash screen Activity launches.
It was important to keep the same class as the launch Activity because the app has already been released, and changing the class of the launch Activity would break shortcuts for users who have already installed the app.
I am working on a complex Android app and found a strange problem.
The problem occurs when I start an activity to show a dialog.
What have I tried
I tried to search for similar problems ("Android activity blocked by home activity" etc) but could not find any.
Due to the complex nature of my app, I still cannot find the minimum representation of the cause -- The Description section below cannot be used to reproduce the problem. It is just something that I think is closely related to the problem. The real cause could be interactions between different subsystems.
Description
The activity is launched by a service with intent flags = FLAG_ACTIVITY_NEW_TASK | FLAG_ACTIVITY_CLEAR_TOP, which ensures that it will be the topmost activity at the point when it's launched. In its onCreate method, the activity set its window flags to be FLAG_SHOW_WHEN_LOCKED | FLAG_FULLSCREEN | FLAG_TURN_SCREEN_ON | FLAG_DISMISS_KEYGUARD, which ensures that even if the screen is locked, the activity will still be displayed. The dialog is also built and shown in the activity's onCreate method.
The app is tested on Android phones with screen pattern locks using the following steps:
Start the app. Press home button to return to the home activity. Remove the app from the recent app list.
Turn off and lock the screen by pressing the power button.
Ask (through GCM, to be specific) the service to launch the activity once. Dialog is then successfully shown.
Don't click any button on the dialog. Lock the screen again.
Ask the service to launch the activity once more. This time the dialog is also shown but instantly disappears, leaving the screen pattern lock shown.
Unlock the pattern lock and something strange appears: The dialog is now shown behind the home activity. The dialog doesn't respond to touch event. It's just like a wallpaper.
Android Version seems to matter
The problem seems to be only affecting some of the versions. It occurred on a Galaxy Nexus (Android 4.4.2) but didn't occur on a Galaxy Tab 3 (Android 4.1).
Accidentally the problem was solved by removing the line
android:theme="#android:style/Theme.Dialog"
for the activity containing the dialog from AndroidManifest.xml.
I am not sure why it could be solved in this way though.
How can i change the screen of an activity when pressing any button on an android phone that takes one away from the running app.
I'm trying to get a blank screen to show up on the "recents" screen, instead of a snapshot of the app.
You can use this option and check if it helps you meet your need.
android:excludeFromRecents="true"
Add this to your activities in the application manifest if you do not want the app to be shown in the recent apps list. One drawback is that you would not be able to resume the app from the Recents list. Not sure if this is what you need.
The other way is to have a 'Blank Activity', which you start when your actual activity pauses. You can then finish the 'Blank Activity' on its Resume. This way, you will have your app shown on the Recents list, but with a blank screen.
You can call finish() for activity but that will kill activity. I think that will leave blank screen. Or destroy(). Try both respond with results.
you might want to change the onpause() or onclose() functions of your app. they are the last thing android execute before leaving,therefor you can change the aspect off your app just before you leave it
EDIT :
Maybe if you create PopupWindow and set it to full screen, and color black when exiting no preview would be shown, but app would still be running (idea of user DjDexter5GH) in the onpause() and onclose() functions. therefgor,when you leave,a black(or whatever you want) screen is pushed in front
you can then close it in the onrestart(is it called this?)
When finishing an activity (landscape), going back to another activity (portrait), the below screen appears. Why? There is no error message.
Add this : android:configChanges="keyboardHidden|orientation" to the Activity inside your AndroidManifest.xml