I have 3 to 4 activities. It moves from 1 activity to another. If I am in 2nd activity then after pressing the back button of emulator it should be open the 1st activity. It opens also
but problem is both activities are connected to database. If in one activity any changes occur then it should appear in other activities.
So what to do here so that refresh of activity can be done in back button also?
you need to override the onresume of the activity you are returning to with your database
Related
I have an app with a main menu at bottom; I can't figure out how should I manage the activity stack, because every button opens an activity, and each activity can start more activities, and i was looking for a management in the style of the current Instagram's app. It looks like (in the Instagram app) that every activity started by each button in the bottom menu opens a new activity stack, but when you press back button, it navigates in the reverse order you called every activity.
Sorry for my bad explanation, i hope that you can understand my aim.
You could check out Instagram Android app to figure out what is my goal.
My current implementation uses a MainActivity with a Fragment for the first menu button (Qui in giro->"Nearby"), but i probably should change this approach.
Thanks.
1) Firstly you will have to decide what will be your main activity.
2) Now use this main activity like as star topology. Means this main activity will be center activity.
3) Use to finish() method for finish back stack before receiving at this center activity.
4) After it if you open another side of your main activity than you will see only new back stack will be displayed after pressing back button for receiving at main activity again.
I am getting problem data loss during application close, is there any idea when user close application any action(like click menu or back button) , I want to display message when actually application close in one step, not back button for different activity.
if i have 5 activity , i want to one step know application close , user running any activity among 5.but here i used back button each 5 activity but i want to one step, and if user click menu at that , i also display message you are going to close application.
Create an Activity class as a BaseActivity and extend it in all 5 activities.
Then override onBackPressed method in BaseActivity.
This way you have not to copy your logic in 5 (or more places).
I have 3 activities ( say A, B, C were A-is the Launch activity). When I press home button when at activity C, app goes into background. After that, I took my app through all apps list menu. At that time, my launch activity is showing (activity A). When I press back button, It goes to previous activity (C). I want to retain in the same activity (C) while coming back from background. When I run application through Eclipse, It works fine. But when I send Apk file through mail and run it in device, It fails (previous problem occurs ).
I tried with
android:launchMode="standard"
AND
android:alwaysRetainTaskState="true"
in my launch activity (Login activity or A). Any body please help me, Thanks in advance.
Follow following steps to insure that you are following the right practice:
1. Make sure you are using finish(); on the Activity A or B if you want to finish it and dont if you want the back button functionality.
2. Try Implementing onpause() and onresume() even if you are not going to perform any functionality in them. Use super() for them there.
3. Also, in android when you start an activity by clicking on the icon instead of resuming it from already running activities, it exhibits a different behaviour.
I have this issue.
I have an actvity A that starts other activity B (by onclick - button).
In B I have one back button to come back to activity A. I press it.
Now that I'm in A, I press again button to go to B.
If I use android back button (I'm in B) I come back to A first and then to B.
But now, if i press android back button again, I don't go to previus activity of A or it exit from app. I come back to B !!!
How can I prevent this behavior ?
The back button of activity B should not start activity A, but close activity B with finish:
http://developer.android.com/reference/android/app/Activity.html#finish%28%29
Note that it is probably bad user interface design to have a "back" button on the interface. This official Android page says "Don't use labeled back buttons"
http://developer.android.com/design/patterns/pure-android.html
if you wish your custom back button to swap between the acivities A and B, you should simply launch intents, that will do.
I believe your problem is with the android back button. If you do not want go to the previous activity with this action, you can write in the manifest file under the <activity> tags for both A and B activities - android:noHistory="true". Doing this will exit from the app. as the activity stack was storing none of the activities, but such a requirement is quite confusing UI approach.
I have activities in sequence as Activity A calling Activity B,When I am on Activity B I press Home button and start another Application (for example Map). If i stay on this second application for a long time say 5-10 minutes and then press Home Button again and choose to Start my application again, then Activity B is started again and works fine. But when i Press Back key - I return to my Activity A again (which is also correct) but it shows a Blank Screen. Ideally in correct version it should show me Acitivty A with the XML data is ListView form.
Alternatively, in the above description, when the other Map Application is started and if the user stay on it only for 1-2 minutes then the above problem doesnt not occur.
Can anyone suggest a solution on the same.
Is it that i need to check in Activity B whether Activity A is still there in Activity Stack (How do i do the same) and If its not in my Activity stack then re-create it.
I tried doing alwaysRetainTaskstate in my Android manifest file for Activity A. But it doesnt work at all
You don't have to do any of that, Android takes care of the technicalities for you - it will recreate your Activity A.
You just need to remember to save A's state when B is opened (take a look at Activity.onSaveInstanceState). When A is restarted, your saved state will be passed to onCreate.
You should really read about Activity Lifecycle
This should help.