假设您有一个DetailActivity，并且需要返回到MainActivity的按钮。首先，将DetailActivity的清单更改为

<activity
    android:name=".DetailActivity"
    android:label="@string/title_activity_detail"
    android:parentActivityName=".MainActivity">
  <meta-data
      android:name="android.support.PARENT_ACTIVITY"
      android:value="com.example.MainActivity"/>
</activity>

以及详细活动的onCreate

getSupportActionBar().setDisplayHomeAsUpEnabled(true);

可以解决问题。这是最简单的实现。

在onCreate()中使用此选项

ActionBar actionBar = getSupportActionBar();
actionBar.setHomeButtonEnabled(true);
actionBar.setDisplayHomeAsUpEnabled(true);

而不是将此侦听器添加到MainActivity.java类中

protected OnBackPressedListener onBackPressedListener;

    public interface OnBackPressedListener {
        void doBack();
    }

    public void setOnBackPressedListener(OnBackPressedListener onBackPressedListener) {
        this.onBackPressedListener = onBackPressedListener;
    }

    @Override
    public void onBackPressed() {
        if (onBackPressedListener != null)
            onBackPressedListener.doBack();
        else
            super.onBackPressed();
}

现在在Fragment类中，您可以实现MainActivity.OnBackPressedListener和：

@Override
public void doBack() {
    //Do on back pressed operation
}

使您的活动扩展AppCompatACtivity，然后将navigationIcon与clicklistener沿着设置为toolbar
例如

public class MyActivity extends AppCompatActivity {

    Toolbar toolbar;

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

        mToolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        toolbar.setNavigationIcon(R.drawable.ic_back_arrow); // Set the icon

        // Icon click listener
        toolbar.setNavigationOnClickListener(new View.OnClickListener() {
            @Override 
            public void onClick(View v) {
                Log.d("cek", "home selected");
            } 
        }); 
    }
}

确保您的活动主题为AppCompat

<style name="AppTheme" parent="Theme.AppCompat.Light">
<!-- Customization will goes here -->
</style>

//In Kotlin
// go to AndroidManifest.xml file apply this change

<activity android:name=".PresentActivity">
            // for adding back button on top
            <meta-data android:name="android.support.PARENT_ACTIVITY"
                android:value=".BackActivity"/>
        </activity>

// Hope this will work.

//对于操作栏上的添加后退按钮==================//将此添加到onCreate方法中..........

getSupportActionBar().setDisplayShowHomeEnabled(true);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

//将此添加到onCreate捆绑包的下面=======

@Override
public boolean onOptionsItemSelected(@NonNull MenuItem item){

    if (item.getItemId()==android.R.id.home){

        this.finish();
    }
    return super.onOptionsItemSelected(item);
}