Develop Reference

Android up button isn't working

I have a simple application. It consists of Activity A and Activity B.
When I start at Activity A (from the launcher icon) and then navigate to Activity B, and then hit the up button. I arrive at Activity A. Perfect.
Yet when I start activity B from the command line (simulating another app or a notification starting this activity) and I hit the up button, I just get taken to the home screen.
Here is my setup:
Activity A
public class ActivityA extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(ActivityA.this, ActivityB.class);
startActivity(intent);
}
});
}
}
Activity B
public class ActivityB extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_b);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
}
}
My manifest. Note that the parent activity is defined and my app min api is 16 (so the parent activity declaration is valid for 16 and up).
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity
android:name=".ActivityA"
android:label="#string/app_name"
android:theme="#style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".ActivityB"
android:exported="true"
android:label="#string/title_activity_b"
android:parentActivityName=".ActivityA"
android:theme="#style/AppTheme.NoActionBar" />
</application>
To start ActivityB from cmd line I use: adb shell am start com.example.demo/com.example.demo.ActivityB
EDIT 1
According to docs here: https://developer.android.com/training/appbar/up-action.html
You do not need to catch the up action in the activity's
onOptionsItemSelected() method. Instead, that method should call its
superclass, as shown in Respond to Actions. The superclass method
responds to the Up selection by navigating to the parent activity, as
specified in the app manifest.
Edit 2:
Just for kicks, I tried the two code snippets here. One at a time to see if they would do the trick. But they don't. ActivityA doesn't open. ActivityB just closes.
https://developer.android.com/training/implementing-navigation/ancestral.html
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
// Respond to the action bar's Up/Home button
case android.R.id.home:
NavUtils.navigateUpFromSameTask(this);
return true;
}
return super.onOptionsItemSelected(item);
}
and
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
// Respond to the action bar's Up/Home button
case android.R.id.home:
Intent upIntent = NavUtils.getParentActivityIntent(this);
if (NavUtils.shouldUpRecreateTask(this, upIntent)) {
// This activity is NOT part of this app's task, so create a new task
// when navigating up, with a synthesized back stack.
TaskStackBuilder.create(this)
// Add all of this activity's parents to the back stack
.addNextIntentWithParentStack(upIntent)
// Navigate up to the closest parent
.startActivities();
} else {
// This activity is part of this app's task, so simply
// navigate up to the logical parent activity.
NavUtils.navigateUpTo(this, upIntent);
}
return true;
}
return super.onOptionsItemSelected(item);
}
What's happening vs expected?
When I open ActivityB via the cmd line and hit up, I expect to go to ActivityA while ActivityB closes. What actually happens is that ActivityB just closes.

That is the default bahavior, the up navigation button works with the Activity Stack, if the ActivityA isn't in the stack, the Android will return to the previous screen , in this case the Home.

Android App Activities Lifecycle

I have a problem that is annoying me. I have made an application that has two activitis. The first activity has a button and when you press the button it starts the second activity. I'm in the second activity and I press the home button to exit the app, and when I reopen the app the activity launched it's the first one. I want to launch the activity where the app was closed, in this case the second one. How can I do it?
public class FirstActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_first);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
View bub = findViewById(R.id.card_ub);
bub.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent1 = new Intent(FisrtActivity.this, SecondActivity.class);
startActivity(intent1);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
// Respond to the action bar's Up/Home button
}
return super.onOptionsItemSelected(item);
}
}
Second Activity -
public class SecondActivityActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
View bub = findViewById(R.id.card_ub);
bub.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent1 = new Intent(FSecondActivity.this, FirstActivity.class);
startActivity(intent1);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
// Respond to the action bar's Up/Home button
}
return super.onOptionsItemSelected(item);
}
}
Manifest file -
<application
android:allowBackup="true"
android:icon="#drawable/dc"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity
android:name=".FirstActivity"
android:label="#string/app_name"
android:screenOrientation="portrait"
android:theme="#style/AppTheme">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".SecondActivity"
android:label="Example"
android:screenOrientation="portrait"
android:theme="#style/AppTheme">
</activity>
</application>
</manifest>

Check developer page for better understanding of backstack.
http://developer.android.com/guide/components/tasks-and-back-stack.html
just call startactivity(new Intent(FirstActivity.this, SecondActivity.class). if you shoould not call finish() when starting new activity. if you are using intent flags like CLEAR_FLAG it will destroy your activity when starting the second activity.

Check your phone setting if you setup "Don't keep background process".
In your case, seems your phone system always kill your application when entering background.
So, if your phone always does that, you can do two things:
close this setting.
Or, you can save activity status in SecondActivity, e.g, onPause / onStop, to let your application know that your current status is SecondActivity.
Next time you open the application, check your application status in FirstActivity, and restore the status to SecondActivity.

Navigate back from settings activity

I'm playing around with Android Studio so I created a SettingsActivity using the wizard and I'm faced with the problem that it is not possible to navigate from this settings activity back to the main activity using the "up" arrow in the Actionbar.
The setup of the Actionbar looks like this:
private void setupActionBar() {
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
// Show the Up button in the action bar.
actionBar.setDisplayShowHomeEnabled(true);
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
Actionbar is not null btw.
And the parentActitvityName is set in the AndroidManifest:
<activity
android:name=".SettingsActivity"
android:label="#string/title_activity_settings"
android:parentActivityName=".MainActivity">
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.demo.app.MainActivity" />
</activity>
However, a click on the arrow does nothing. Not even onOptionsItemSelected gets triggered.
Seems like this is exactly the same problem
Action bar setDisplayHomeAsUpEnabled not working on ICS but navigating back from a detail to an overview activity is working fine in the very same app. Moreover I set MinSDK to 15 and TargetSDK to 23.

override the onOptionsItemSelected method on your AppCompatPrefernceActivity and make it like this
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
// Respond to the action bar's Up/Home button
case android.R.id.home:
super.onBackPressed();
return true;
}
return super.onOptionsItemSelected(item);
}

Vspallas answer is correct. The mistake was on my side. I had an onOptionsItemSelected method inside the preferenceFragment, not in the Activity. Mea culpa.

You can use this inside the settings activity
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
NavUtils.navigateUpFromSameTask(this);
return true;
default:
return super.onOptionsItemSelected(item);
}
}
Then in androidManifest is the same as that you have did
<activity
android:name=".SettingsActivity"
android:parentActivityName=".MainActivity"
android:label="#string/title_activity_settings">
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.app_name.MainActivity" />
</activity>
this com.example.app_name is you App package name

NavUp Button not working

I have a Main Activity which contains two Fragment A(Tab1) and B(Tab2). From B(Tab2), i have created a activity(CategoryBlogs). Now i want to go back from activity (CategoryBlogs) to Tab2. but when i presses the NavUp button on custom ActionBar , nothings happens
CategoryBlogs.java
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_category__blogs);
listView = (ListView) findViewById(android.R.id.list);
Toolbar tool_bar1 = (Toolbar) findViewById(R.id.tool_bar);
setSupportActionBar(tool_bar1);
getSupportActionBar().setDisplayShowHomeEnabled(true);
getSupportActionBar().setIcon(R.drawable.ic_launcher);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
Intent intent = getIntent();
String message = intent.getStringExtra(Tab2.EXTRA_MESSAGE);
String link = message.trim() + "?feed=titles";
Log.d("ye category click krne par next activity me ye link bnta hy parsing ke liye",link);
loadPage(link);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_category__blogs, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
Log.d("hum option item selected me a gae", id+"");
if(id==android.R.id.home){
NavUtils.navigateUpFromSameTask(this);
Log.d("hum match kr gae", id+"");
return true;
}
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
AndroidManifest.XML
<activity
android:name=".Category_Blogs"
android:label="App For Blog" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.talha.test_fragement.MainActivity"
/>
</activity>
</application>

add in onCreate
setHasOptionsMenu(true);
and debug onOptionsItemSelected is it execute or not..

You haven't specified the android:parentActivityName to which you are supposed to Navigate up in the AndroidManifest.xml file under activity tag.
android:parentActivityName="com.example.myfirstapp.MainActivity" >
Here's everything you need to know about Navigating Up
1. Specify the Parent Activity in manifest.xml
<activity
android:name="com.example.myfirstapp.DisplayMessageActivity"
android:label="#string/title_activity_display_message"
android:parentActivityName="com.example.myfirstapp.MainActivity" >
<!-- Parent activity meta-data to support 4.0 and lower -->
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.myfirstapp.MainActivity" />
</activity>
2. Add Up Action in Activity (For the ActionBar <-)
getActionBar().setDisplayHomeAsUpEnabled(true);
3. Navigate up to Parent by overriding onOptionsItemSelected() method
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
// Respond to the action bar's Up/Home button
case android.R.id.home:
NavUtils.navigateUpFromSameTask(this);
return true;
}
return super.onOptionsItemSelected(item);
}
For more information, follow this link http://developer.android.com/training/implementing-navigation/ancestral.html

You have to get parent activity and
You have to replace this block of code -
NavUtils.navigateUpFromSameTask(this);
with this:
Intent intent = NavUtils.getParentActivityIntent(this); //get parent activity
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
NavUtils.navigateUpTo(this, intent); // and navigate your current activity to your parent activity
You've also tried to change the launchMode in the manifest at the <activity> element to
android:launchMode="singleTop"
or
android:launchMode="singleTask
There can be many solutions to solve your problem.

Add back button to action bar

I have been trying to add a back button to the action bar.
I want my view to look like this:
I want to add the back button in the left of the action bar.
I added this code
ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
but it doesn't work.
How can I fix this?

After setting
actionBar.setHomeButtonEnabled(true);
Add the following code:
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
// app icon in action bar clicked; goto parent activity.
this.finish();
return true;
default:
return super.onOptionsItemSelected(item);
}
}

Add
actionBar.setHomeButtonEnabled(true);
and then add the following
#Override
public boolean onOptionsItemSelected(MenuItem menuItem)
{
switch (menuItem.getItemId()) {
case android.R.id.home:
onBackPressed();
return true;
default:
return super.onOptionsItemSelected(menuItem);
}
}
As suggested by naXa I've added a check on the itemId, to have it work correctly in case there are multiple buttons on the action bar.

this one worked for me:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_your_activity);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
// ... other stuff
}
#Override
public boolean onSupportNavigateUp(){
finish();
return true;
}
The method onSupportNavigateUp() is called when you use the back button in the SupportActionBar.

After setting
actionBar.setHomeButtonEnabled(true);
You have to configure the parent activity in your AndroidManifest.xml
<activity
android:name="com.example.MainActivity"
android:label="#string/app_name"
android:theme="#style/Theme.AppCompat" />
<activity
android:name="com.example.SecondActivity"
android:theme="#style/Theme.AppCompat" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.MainActivity" />
</activity>
Look here for more information http://developer.android.com/training/implementing-navigation/ancestral.html

There are two ways to approach this.
Option 1: Update the Android Manifest
If the settings Activity is always called from the same activity, you can make the relationship in the Android Manifest. Android will automagically show the 'back' button in the ActionBar
<activity
android:name=".SettingsActivity"
android:label="Setting Activity">
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.example.MainActivity" />
</activity>
Option 2: Change a setting for the ActionBar
If you don't know which Activity will call the Settings Activity, you can create it like this. First in your activity that extends ActionBarActivity (Make sure your #imports match the level of compatibility you are looking for).
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_settings_test);
ActionBar actionBar = getSupportActionBar();
actionBar.setHomeButtonEnabled(true);
actionBar.setDisplayHomeAsUpEnabled(true);
}
Then, detect the 'back button' press and tell Android to close the currently open Activity.
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
// app icon in action bar clicked; goto parent activity.
this.finish();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
That should do it!

Firstly Use this:
ActionBar bar = getSupportActionBar();
bar.setDisplayHomeAsUpEnabled(true);
Then set operation of button click in onOptionsItemSelected method
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
finish();
return true;
default:
return super.onOptionsItemSelected(item);
}
}

You'll need to check menuItem.getItemId() against android.R.id.home in the onOptionsItemSelected method
Duplicate of Android Sherlock ActionBar Up button

Simpler and better:
For API >= 16
Simply add "parentActivityName" for each activity in Manifest. The back button will automatically take u to the parent activity.
<activity
android:name="com.example.myfirstapp.DisplayMessageActivity"
android:label="#string/title_activity_display_message"
android:parentActivityName="com.example.myfirstapp.MainActivity" >

Use this to show back button and move to previous activity,
final ActionBar actionBar = getSupportActionBar();
assert actionBar != null;
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setHomeAsUpIndicator(R.drawable.back_dark);
#Override
public boolean onOptionsItemSelected(final MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
onBackPressed();
return true;
default:
return super.onOptionsItemSelected(item);
}
}

if anyone else need the solution
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
onBackPressed();
}
return super.onOptionsItemSelected(item);
}

Add this line in onCreate() method
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
then Override this method
#Override
public boolean onSupportNavigateUp(){
finish();
return true;
}