操作栏后退按钮未在Android中显示

Question

您好我已经创建了一个活动,ActionBarActivity在我的应用程序中扩展和使用材料主题.在操作栏中,不显示"后退"按钮.

我没有找到它为什么没有显示.有帮助吗？

public class RegistrationActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_registration);

        getSupportActionBar().setBackgroundDrawable(getResources().getDrawable(R.drawable.ab_background_light));
        getSupportActionBar().setDisplayShowHomeEnabled(true);
        getSupportActionBar().setHomeButtonEnabled(true);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);

style.xml

<style name="AppTheme" parent="Theme.AppCompat.Light">
    <!--Support Library compatibility-->
    <item name="actionBarStyle">@style/MyTheme.ActionBarStyle</item>
</style>

<!-- ActionBar styles -->
<style name="MyTheme.ActionBarStyle" parent="@style/Widget.AppCompat.Light.ActionBar">
    <!--Support Library compatibility-->
    <item name="titleTextStyle">@style/MyTheme.ActionBar.TitleTextStyle</item>
</style>

<style name="MyTheme.ActionBar.TitleTextStyle" parent="@style/TextAppearance.AppCompat.Widget.ActionBar.Title">
    <item name="android:textColor">@android:color/white</item>
</style>

AndroidManifest.xml中

    <activity
        android:name=".RegistrationActivity"
        android:label="@string/title_activity_registration" >
        <meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value=".HomeScreenActivity" />
    </activity>

提前致谢.

Answer 1

添加属性

getSupportActionBar().setDisplayHomeAsUpEnabled(true);

显示"后退按钮"

Answer 2

如果Jorgesys的解决方案不适合您。尝试覆盖该onOptionsItemSelected方法。

public class MyActivity extends AppCompatActivity
{

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.my_activity);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item)
    {
        int id = item.getItemId();
        if (id == android.R.id.home)
        {
            onBackPressed();
            return true;
        }
        else
        {
            return super.onOptionsItemSelected(item);
        }
    }
}