Add back button to action bar

问题:

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?

回答1:

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);
    }
}

回答2:

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.

回答3:

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.

回答4:

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

回答5:

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!

回答6:

You'll need to check menuItem.getItemId() against android.R.id.home in the onOptionsItemSelected method

Duplicate of Android Sherlock ActionBar Up button

回答7:

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" >

回答8:

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);
        }
    }

回答9:

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);
}

回答10:

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);
  }
 }

回答11:

Add this line in onCreate() method

getSupportActionBar().setDisplayHomeAsUpEnabled(true);

then Override this method

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