Display back button on action bar

问题:

I'm trying to display a Back button on the Action bar to move previous page/activity or to the main page (first opening). And I can not do it.

my code.

ActionBar actionBar = getActionBar(); actionBar.setHomeButtonEnabled(true); 

the code is in onCreate.

回答1:

well this is simple one to show back button

actionBar.setDisplayHomeAsUpEnabled(true); 

and then you can custom the back event at onOptionsItemSelected

case android.R.id.home: this.finish(); return true; 

回答2:

I think onSupportNavigateUp() is best and Easiest way to do so, check the code below.

if you want it programmatically Add this line in onCreate() method

getSupportActionBar().setDisplayHomeAsUpEnabled(true);   

Note: make sure Actionbar is not null.

And Override this method

@Override public boolean onSupportNavigateUp(){       finish();       return true;   } 

thats it
OR Non-programmatically you can add meta to the activity in manifest file as

Edit: If you are not using AppCompat Activity then do not use support word, you can use

getActionBar().setDisplayHomeAsUpEnabled(true); // In `OnCreate();`  @Override  public boolean onNavigateUp(){       finish();       return true;  } 

Thanks to @atariguy for comment.

回答3:

The magic happens in onOptionsItemSelected.

@Override public boolean onOptionsItemSelected(MenuItem item) {     switch (item.getItemId()) {         case android.R.id.home:             // app icon in action bar clicked; go home             Intent intent = new Intent(this, HomeActivity.class);             intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);             startActivity(intent);             return true;         default:             return super.onOptionsItemSelected(item);     } } 

回答4:

Official solution

Add those two code snippets to your SubActivity

@Override public void onCreate(Bundle savedInstanceState) {     ...     getActionBar().setDisplayHomeAsUpEnabled(true); }  @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); } 

add meta-data and parentActivity to manifest to support lower sdk.

      ...                   ...     

Reference here:http://developer.android.com/training/implementing-navigation/ancestral.html

回答5:

Add these lines to onCreate()

android.support.v7.app.ActionBar actionBar = getSupportActionBar();    actionBar.setHomeButtonEnabled(true);    actionBar.setDisplayHomeAsUpEnabled(true); 

and in onOptionItemSelected

@Override     public boolean onOptionsItemSelected(MenuItem item) {         switch (item.getItemId()) {             case android.R.id.home:                 //Write your logic here                 this.finish();                 return true;             default:                 return super.onOptionsItemSelected(item);         }     } 

Hope this will help you..!

回答6:

Try this code, considers it only if you need the back button.

@Override protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     //YOUR CODE     getSupportActionBar().setDisplayHomeAsUpEnabled(true);      //YOUR CODE }  @Override public boolean onOptionsItemSelected(MenuItem item) {     onBackPressed();     return true; } 

回答7:

On your onCreate method add:

getSupportActionBar().setDisplayHomeAsUpEnabled(true); 

While defining in the AndroidManifest.xml the parent activity (the activity that will be called once the back button in the action bar is pressed):

In your definition on the Manifest, add the line:

android:parentActivityName="com.example.activities.MyParentActivity" 

回答8:

I know I'm a bit late, but was able to fix this issue by following the docs directly.

Add the meta-data tag to AndroidManifest.xml (so the system knows)

Next, enable the back (up) button in your MainActivity

    @Override      protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.activity_my_child);      // my_child_toolbar is defined in the layout file      Toolbar myChildToolbar =         (Toolbar) findViewById(R.id.my_child_toolbar);     setSupportActionBar(myChildToolbar);      // Get a support ActionBar corresponding to this toolbar      ActionBar ab = getSupportActionBar();      // Enable the Up button      ab.setDisplayHomeAsUpEnabled(true);     }  

And, you will be all set up!

Source: Android Developer Documentation

回答9:

I know that the above are many helpful solutions, but this time I read this article (current Android Studio 2.1.2 with sdk 23) some method above doesn't work.

Below is my solution for sub-activity is MapsActivity

First, you need to add parentActivity in

AndroidManifest.xml

like this :

     ...                   ...     

Second, ensure that your sub-Activity extends AppCompatActivity, not FragmentActivity.

Third, override onOptionsItemSelected() method

@Override     public boolean onOptionsItemSelected(MenuItem item) {         switch (item.getItemId()) {             case android.R.id.home:                 // app icon action bar is clicked; go to parent activity                 this.finish();                 return true;             case R.id.action_settings:                 return true;             default:                 return super.onOptionsItemSelected(item);         }     } 

Hope this will help!

回答10:

To achieve this, there are simply two steps,

Step 1: Go to AndroidManifest.xml and add this parameter in the tag - android:parentActivityName=".home.HomeActivity"

Example:

Step 2: In ActivityDetail add your action for previous page/activity

Example:

@Override public boolean onOptionsItemSelected(MenuItem item) {     switch (item.getItemId()) {         case android.R.id.home:             onBackPressed();             return true;     }     return super.onOptionsItemSelected(item); } 

回答11:

Try this, In your onCreate()

 getActionBar().setHomeButtonEnabled(true);  getActionBar().setDisplayHomeAsUpEnabled(true); 

And for clickevent,

@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);         }     } 

回答12:

I Solved in this way

@Override public boolean  onOptionsItemSelected(MenuItem item){     switch (item.getItemId()) {         case android.R.id.home:             onBackPressed();             finish();             return true;         default:             return super.onOptionsItemSelected(item);     } }  @Override public void onBackPressed(){     Intent backMainTest = new Intent(this,MainTest.class);     startActivity(backMainTest);     finish(); } 

回答13:

 public void initToolbar(){        //this set back button         getSupportActionBar().setDisplayHomeAsUpEnabled(true);        //this is set custom image to back button        getSupportActionBar().setHomeAsUpIndicator(R.drawable.back_btn_image); }   //this method call when you press back button @Override public boolean onSupportNavigateUp(){     finish();     return true; } 

回答14:

my working code to go back screen.

@Override public boolean onOptionsItemSelected(MenuItem item) {      switch (item.getItemId()) {      case android.R.id.home:          Toast.makeText(getApplicationContext(), "Home Clicked",                 Toast.LENGTH_LONG).show();          // go to previous activity         onBackPressed();          return true;      }      return super.onOptionsItemSelected(item); } 

文章来源: Display back button on action bar