I am simply trying to click back and navigate to my previous activity. My flow is this: I go to news_feed activity -> Comments activity -> User Profile activity -> click back (Go to Comments activity) -> click back (This does nothing for some reason) -> Click back (Go back to news_feed activity). I'm not sure why I have to click back twice when I try to go from Comments activity back to news_feed activity. If I go from news_feed activity -> Comments -> press back (Go to news_feed activity) this works perfectly. Here is my code:
news_feed.java:
#Override
public void onBackPressed() {
super.onBackPressed();
Intent startMain = new Intent(Intent.ACTION_MAIN);
startMain.addCategory(Intent.CATEGORY_HOME);
startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(startMain);
}
Comments.java:
#Override
public void onBackPressed() {
super.onBackPressed();
this.finish();
}
UserProfile.java:
#Override
public void onBackPressed() {
super.onBackPressed();
Intent intent = new Intent(UserProfile.this, Comments.class);
Bundle bundle = new Bundle();
bundle.putString("postId", postId);
bundle.putString("posterUserId", posterUserId);
bundle.putString("posterName", posterName);
bundle.putString("postStatus", postStatus);
bundle.putString("postTimeStamp", postTimeStamp);
bundle.putString("postTitle", postTitle);
intent.putExtras(bundle);
startActivity(intent);
finish();
}
I don't think navigating to these activities would change anything, but I can include the intents that I used to navigate to these activities also if necessary. Otherwise I just included the onBackPressed code that I had for these activities. Any ideas why this might cause a problem? Any help would be appreciated. Thanks.
In your UserProfile class, in onBackPressed() method, you are starting the Comments class again. Why do you have to do this?
What is happening is, you are starting a new Comments activity onBackPressed() of the USerProfile class, so there are two instances of Comments Activity. So you feel you are pressing back btn twice.
If you have to pass data back to Comments from UserProfile class, then make use of setResult() method.
This will be of help
How to pass data from 2nd activity to 1st activity when pressed back? - android
Sending data back to the Main Activity in android
I you want to send back the result to previous activity the start activity by using
startActivityForResult()
insead of
startActivity()
and don't override
onBackPressed()
You can try something like this:
private boolean clicked;
#Override
public void onBackPressed() {
if (!clicked) { // if it was not clicked before, change the value of clicked to true and do nothing directly return, if clicked again, then it will be finish the activity.
clicked=true;
return;
}
super.onBackPressed();
}
And if you are going to use the time, then you can do like this:
private long lastClicked;
#Override
public void onBackPressed() {
if (System.currentTimeMillis() - lastClicked < 1000) { // within one second
super.onBackPressed();
}
lastClicked = System.currentTimeMillis();
}
You don't need to override onBackPressed() if all you're going to do is call startActivity() and finish() in the current activity. The Android backstack will handle both of those for you. Moreover, in your UserProfile.java you are passing data to previous activity. For this, you should use startActvityForResult() in the Comments activity (i.e the previous activity) instead of startActivity().
To learn more about startActvityForResult() visit: https://developer.android.com/training/basics/intents/result.html
public void onBackPressed() {
if (this.lastBackPressTime < System.currentTimeMillis() - 2000) {
this.lastBackPressTime = System.currentTimeMillis();
} else {
//super.onBackPressed(); for exit
//INTENT HERE TO YOUR SECOND ACTIVITY like below
Intent intent=new Intent(A.this,B.class);
startActivirty(intent);
}
}
Create a global variable
private long lastBackPressTime = 0;
Hope this will help you,Let me know..
Related
I have a subActivity that can be open from my mainActivity.
For some reasons, when the user clicks on the back button go back to my mainActivity, I want my subActivity to remain open in background in order to be able to come back for later.
Questions:
how to avoid to close the subActivity when the user clicks back ?
how to come back to the mainActivity without restarting it ?
how to come back later to my opened activity without re-creating it completely ? (just want to bring it to front)
Thanks !
On you subActivity onBackPressed() add this
#Override
public void onBackPressed() {
Intent i = new Intent(SubActivity.this, MainActivity.class);
i.setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
startActivity(i);
}
on mainActivity :
private void openSubActivity() {
Intent intent = new Intent(MainActivity.this,SubActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_REORDER_TO_FRONT);
startActivity(intent);
}
override onBackPressed() and remove super from it then try opening the activity which you want to open from there for ex-
#Override
public void onBackPressed() {
// your code
}
and with the help of different activity launch modes you can achieve it
I am not sure this workaround is the correct way to achieve my goal of having a prompt text in a spinner. What happens with this application is the spinner navigates to another Activity via an Intent and when the user navigates back to the Main Activity with the spinner they have two ways back. One with a Button and a click event the other by clicking the device BACK button. I am trying to call the code in the click event from the method that manages the device BACK button
I do not know how to call the click event from the device BACK button Method
#Override
public void onBackPressed() {
Toast.makeText(getApplicationContext(),"Use BACK BUTTON\n\n"+"On the Screen",Toast.LENGTH_LONG).show();
// I want to call goBack(View view) from here
// +++++++++++++++++++++++++++++++++++++++++++
}
public void goBack(View view){
Intent i = new Intent( PageTwo.this, MainActivity.class );
startActivity( i );
}
The reason I use this Intent to navigate BACK to the Main Activity is it reloads the variables in the Spinner
It looks like goBack(View) is most likely from an onClick setup in your layout XML. Since you aren't using the view, just pass null:
#Override public void onBackPressed() {
goBack(null);
}
I don't know if I get you right, if you just want to go back to the activity which started another activity, you can just call finish() method of Activity class:
#Override
public void onBackPressed() {
finish();
}
finish() reference
When a user presses the back button on an intent, the application should quit. How can I ensure the application quits when the back button is pressed?
In my Home Activity I override the "onBackPressed" to:
#Override
public void onBackPressed() {
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
so if the user is in the home activity and press back, he goes to the home screen.
I took the code from Going to home screen Programmatically
Immediately after you start a new activity, using startActivity, make sure you call finish() so that the current activity is not stacked behind the new one.
EDIT
With regards to your comment:
What you're suggesting is not particularly how the android app flow usually works, and how the users expect it to work. What you can do if you really want to, is to make sure that every startActivity leading up to that activity, is a startActivityForResult and has an onActivityResult listener that checks for an exit code, and bubbles that back. You can read more about that here. Basically, use setResult before finishing an activity, to set an exit code of your choice, and if your parent activity receives that exit code, you set it in that activity, and finish that one, etc...
A better user experience:
/**
* Back button listener.
* Will close the application if the back button pressed twice.
*/
#Override
public void onBackPressed()
{
if(backButtonCount >= 1)
{
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
else
{
Toast.makeText(this, "Press the back button once again to close the application.", Toast.LENGTH_SHORT).show();
backButtonCount++;
}
}
The app will only exit if there are no activities in the back stack. SO add this line in your manifest android:noHistory="true" to all the activities that you dont want to be back stacked.And then to close the app call the finish() in the OnBackPressed
<activity android:name=".activities.DemoActivity"
android:screenOrientation="portrait"
**android:noHistory="true"**
/>
Why wouldn't the user just hit the home button? Then they can exit your app from any of your activities, not just a specific one.
If you are worried about your application continuing to do something in the background. Make sure to stop it in the relevant onPause and onStop commands (which will get triggered when the user presses Home).
If your issue is that you want the next time the user clicks on your app for it to start back at the beginning, I recommend putting some kind of menu item or UI button on the screen that takes the user back to the starting activity of your app. Like the twitter bird in the official twitter app, etc.
Use onBackPressedmethod
#Override
public void onBackPressed() {
finish();
super.onBackPressed();
}
This will solve your issue.
First of all, Android does not recommend you to do that within the back button, but rather using the lifecycle methods provided. The back button should not destroy the Activity.
Activities are being added to the stack, accessible from the Overview (square button since they introduced the Material design in 5.0) when the back button is pressed on the last remaining Activity from the UI stack. If the user wants to close down your app, they should swipe it off (close it) from the Overview menu.
Your app is responsible to stop any background tasks and jobs you don't want to run, on onPause(), onStop() and onDestroy() lifecycle methods. Please read more about the lifecycles and their proper implementation here: http://developer.android.com/training/basics/activity-lifecycle/stopping.html
But to answer your question, you can do hacks to implement the exact behaviour you want, but as I said, it is not recommended:
#Override
public void onBackPressed() {
// make sure you have this outcommented
// super.onBackPressed();
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
To exit from an Android app, just simply use.
in your Main Activity, or you can use Android manifest file to set
android:noHistory="true"
finish your current_activity using method finish() onBack method of your current_activity
and then add below lines in onDestroy of the current_activity for Removing Force close
#Override
public void onDestroy()
{
android.os.Process.killProcess(android.os.Process.myPid());
super.onDestroy();
}
I modified #Vlad_Spays answer so that the back button acts normally unless it's the last item in the stack, then it prompts the user before exiting the app.
#Override
public void onBackPressed(){
if (isTaskRoot()){
if (backButtonCount >= 1){
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}else{
Toast.makeText(this, "Press the back button once again to close the application.", Toast.LENGTH_SHORT).show();
backButtonCount++;
}
}else{
super.onBackPressed();
}
}
you can simply use this
startActivity(new Intent(this, Splash.class));
moveTaskToBack(true);
The startActivity(new Intent(this, Splash.class)); is the first class that will be lauched when the application starts
moveTaskToBack(true); will minimize your application
Add this code in the activity from where you want to exit from the app on pressing back button:
#Override
public void onBackPressed() {
super.onBackPressed();
exitFromApp();
}
private void exitFromApp() {
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
startActivity(intent);
}
I want to do something simple on android app.
How is it possible to go back to a previous activity.
What code do I need to go back to previous activity
Android activities are stored in the activity stack. Going back to a previous activity could mean two things.
You opened the new activity from another activity with startActivityForResult. In that case you can just call the finishActivity() function from your code and it'll take you back to the previous activity.
Keep track of the activity stack. Whenever you start a new activity with an intent you can specify an intent flag like FLAG_ACTIVITY_REORDER_TO_FRONT or FLAG_ACTIVITY_PREVIOUS_IS_TOP. You can use this to shuffle between the activities in your application. Haven't used them much though. Have a look at the flags here: http://developer.android.com/reference/android/content/Intent.html
As mentioned in the comments, if the activity is opened with startActivity() then one can close it with finish().
If you wish to use the Up button you can catch that in onOptionsSelected(MenuItem item) method with checking the item ID against android.R.id.home unlike R.id.home as mentioned in the comments.
Try Activity#finish(). This is more or less what the back button does by default.
Just write on click finish(). It will take you to the previous Activity.
Just this
super.onBackPressed();
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
This will get you to a previous activity keeping its stack and clearing all activities after it from the stack.
For example, if stack was A->B->C->D and you start B with this flag, stack will be A->B
Just call these method to finish current activity or to go back by onBackPressed
finish();
OR
onBackPressed();
Are you wanting to take control of the back button behavior? You can override the back button (to go to a specific activity) via one of two methods.
For Android 1.6 and below:
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0) {
// do something on back.
return true;
}
return super.onKeyDown(keyCode, event);
}
Or if you are only supporting Android 2.0 or greater:
#Override
public void onBackPressed() {
// do something on back.
return;
}
For more details: http://android-developers.blogspot.com/2009/12/back-and-other-hard-keys-three-stories.html
Try this is act as you have to press the back button
finish();
super.onBackPressed();
Add this in your onCLick() method, it will go back to your previous activity
finish();
or You can use this. It worked perfectly for me
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if ( id == android.R.id.home ) {
finish();
return true;
}
return super.onOptionsItemSelected(item);
}
if you want to go to just want to go to previous activity use
finish();
OR
onBackPressed();
if you want to go to second activity or below that use following:
intent = new Intent(MyFourthActivity.this , MySecondActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
//Bundle is optional
Bundle bundle = new Bundle();
bundle.putString("MyValue1", val1);
intent.putExtras(bundle);
//end Bundle
startActivity(intent);
If you have setup correctly the AndroidManifest.xml file with activity parent, you can use :
NavUtils.navigateUpFromSameTask(this);
Where this is your child activity.
Got the same problem and
finish(); OR super.onBackPressed();
worked fine for me, both worked same, but no luck with return
You can explicitly call onBackPressed is the easiest way
Refer Go back to previous activity for details
Start the second activity using intent (either use startActivity or startActivityForResult according to your requirements). Now when user press back button, the current activity on top will be closed and the previous will be shown.
Now Lets say you have two activities, one for selecting some settings for the user, like language, country etc, and after selecting it, the user clicks on Next button to go to the login form (for example) . Now if the login is unsuccessful, then the user will be on the login activity, what if login is successful ?
If login is successful, then you have to start another activity. It means a third activity will be started, and still there are two activities running. In this case, it will be good to use startActivityForResult. When login is successful, send OK data back to first activity and close login activity. Now when the data is received, then start the third activity and close the first activity by using finish.
You can try this:
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0) {
finish();
return true;
}
return super.onKeyDown(keyCode, event);
}
All new activities/intents by default have back/previous behavior, unless you have coded a finish() on the calling activity.
#Override
public void onBackPressed() {
super.onBackPressed();
}
and if you want on button click go back then simply put
bbsubmit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onBackPressed();
}
});
I suggest the NavUtils.navigateUpFromSameTask(), it's easy and very simple, you can learn it from the google developer.Wish I could help you!
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if ( id == android.R.id.home ) {
finish();
return true;
}
return super.onOptionsItemSelected(item);
}
Try this it works both on toolbar back button as hardware back button.
There are few cases to go back to your previous activity:
Case 1: if you want take result back to your previous activity then
ActivityA.java
Intent intent = new Intent(ActivityA.this, FBHelperActivity.class);
startActivityForResult(intent,2);
FBHelperActivity.java
Intent returnIntent = new Intent();
setResult(RESULT_OK, returnIntent);
finish();
Case 2: ActivityA --> FBHelperActivity---->ActivityA
ActivityA.java
Intent intent = new Intent(ActivityA.this, FBHelperActivity.class);
startActivity(intent);
FBHelperActivity.java
after getting of result call finish();
By this way your second activity will finish and because
you did not call finish() in your first activity then
automatic first activity is in back ground, will visible.
Besides all the mentioned answers, their is still an alternative way of doing this, lets say you have two classes , class A and class B.
Class A you have made some activities like checkbox select, printed out some data and intent to class B.
Class B, you would like to pass multiple values to class A and maintain the previous state of class A, you can use, try this alternative method or download source code to demonstrate this
http://whats-online.info/science-and-tutorials/125/Android-maintain-the-previous-state-of-activity-on-intent/
or
http://developer.android.com/reference/android/content/Intent.html
Just try this in,
first activity
Intent mainIntent = new Intent(Activity1.this, Activity2.class);
this.startActivity(mainIntent);
In your second activity
#Override
public void onBackPressed() {
this.finish();
}
First, thing you need to keep in mind that, if you want to go back to a previous activity. Then don't call finish() method when goes to another activity using Intent.
After that you have two way to back from current activity to previous activity:
Simply call:
finish()
OR
super.onBackPressed();
To go back from one activity to another by clicking back button use the code given below use current activity name and then the target activity.
#Override
public void onBackPressed() {
// do something on back.
startActivity(new Intent(secondActivity.this, MainActivity.class));
return;
}
I have three activities: First, Second and Third. I used this method in Second activity:
public void onBackPressed() {
super.onBackPressed();
finish();
}
and this on Third activity:
public void onBackPressed() {
super.onBackPressed();
Intent i = new Intent(Third.this, Second.class);
startActivity(i);
finish();
}
The problem is when I press back button after coming from the Third activity, I am going into First activity instead of finish(). I am successfully exiting the application when I click back button right after coming from first activity but not after coming from Third activity.
How to solve this problem?
EDIT: Thanks for the answers guys,the answer of "Ved Prakash" solved the problem for me.But i have a weird problem now.When i press back button the app is successfully exiting but the app which i minimized to Recent Apps button is coming on to the screen and exiting.For example,if i have opened Setting app before opening my app,when i press back button,my app is exiting and immediately Settings app is also opening and exiting itself.What might be the problem?
Your problem is that you don't seem to understand how Activities work. The finish() function ends the current Activity, and then you receive the previous Activity from the backstack.
My recommendation is that you should use a single Activity, and hold Fragments inside it. If you want it so that pressing the Back button ends the application at any screen that is displayed, you could do the following:
Activity XML:
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/initial_container"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
Activity that holds the Fragments:
public class InitialActivity extends FragmentActivity implements ReplaceWith
{
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_initial);
getSupportFragmentManager().addOnBackStackChangedListener(new OnBackStackChangedListener()
{
public void onBackStackChanged()
{
int backCount = getSupportFragmentManager().getBackStackEntryCount();
if (backCount == 0)
{
finish();
}
}
});
if (savedInstanceState == null)
{
getSupportFragmentManager().beginTransaction().add(R.id.initial_container, new FirstFragment()).commit();
}
}
#Override
public void replaceWith(Fragment fragment)
{
getSupportFragmentManager().beginTransaction().replace(R.id.initial_container, fragment).commit();
}
}
Example for a Fragment:
public class FirstFragment extends Fragment implements View.OnClickListener
{
private ReplaceWith activity_replaceWith;
private ImageView exampleImage;
public FirstFragment()
{
super();
}
#Override
public void onAttach(Activity activity)
{
super.onAttach(activity);
try
{
activity_replaceWith = (ReplaceWith) activity;
}
catch (ClassCastException e)
{
Log.e(getClass().getSimpleName(), "Activity of " + getClass().getSimpleName() + "must implement ReplaceWith interface!", e);
throw e;
}
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
{
View rootView = inflater.inflate(R.layout.fragment_first, container, false);
exampleImage = (ImageView) rootView.findViewById(R.id.fragment_first_example_image);
exampleImage.setOnClickListener(this);
return rootView;
}
#Override
public void onClick(View v)
{
if(v == exampleImage)
{
activity_replaceWith.replaceWith(new SecondFragment());
//please note that this should be done only if you are planning
//only on single-screen applications
//with no other layouts based on orientation or size
//otherwise, the Activity needs to be responsible for this, not the Fragment
}
}
}
This way, when you press the Back button, your application would end from any displayed screen.
Ok your code is wrong.
If you will look at activity source, you see that activity.onBackPressed() is calling finish(). So if call super.onBackPressed() you don't need to call finish.
Finish() is not stopping your application, it's stopping current activity.
Your code on third activity very strange. You are trying to stop activity and start another same activity.
What exactly you want to achieve?
If you want to exit application from your third activity, you need to clear your backstack. But I think you have problem with structure of your app.
Ok. then you should finish your first activity when you go to second activity like this(If you are using intent for that):
Intent it=new Intent(FirstActivity.this,SecondActivity.class);
finish();
startactivity(it);
and same for Second Activity:
Intent it=new Intent(SecondActivity.this,ThirdActivity.class);
finish();
startactivity(it);
this done your work...when you are in third activity the above activities are finished..
and when you press backButton you will be exit from application..
Good luck.
You can use -
public static final int FLAG_ACTIVITY_CLEAR_TOP
If set, and the activity being launched is already running in the
current task, then instead of launching a new instance of that
activity, all of the other activities on top of it will be closed and
this Intent will be delivered to the (now on top) old activity as a
new Intent.
And here is how -
When the user wishes to exit all open activities, they should press a button which loads the first Activity that runs when your app starts, in my case "MainActivity".
Intent intent = new Intent(getApplicationContext(), LoginActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intent.putExtra("EXIT", true);
startActivity(intent);
The above code clears all the activities except for LoginActivity. LoginActivity is the first activity that is brought up when the user runs the program. Then put this code inside the LoginActivity's onCreate, to signal when it should self destruct when the 'Exit' message is passed.
if (getIntent().getBooleanExtra("EXIT", false)) {
finish();
}
This explanation part is also introduced at exit-an-android-app.