java - 如何在 Java 中创建 ActionBar/ToolBar

Question

我正在尝试以编程方式在 DrawerLayout 中创建 ActionBar，如下所示:

import android.support.v7.widget.Toolbar;

public class RevToolBar extends MainActivity {

    public Toolbar getRevToolbar() {
        Toolbar revToolBar = new Toolbar( this );
        setSupportActionBar(revToolBar);

        return revToolBar;
    }
}

然后在主要 Activity 中:

public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener {

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

        Toolbar toolbar = new RevToolBar().getRevToolbar();

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
    }

但是，应用程序总是在启动后崩溃:

App has stopped
Open app again

在 Java 中创建 ActionBar/Toolbar 并将其添加到 DrawerLayout 的正确方法是什么？

提前谢谢大家。

更新

抛出的输出:

07/10 14:16:22: Launching app
$ adb install-multiple -r -p com.example.rev.myapp /media/rev/5431214957EBF5D7/projects/android/myapp/app/build/intermediates/split-apk/debug/slices/slice_0.apk 
Split APKs installed
$ adb shell am start -n "com.example.rev.myapp/com.example.rev.myapp.MainActivity" -a android.intent.action.MAIN -c android.intent.category.LAUNCHER
Client not ready yet..Waiting for process to come online
Connected to process 9754 on device Nexus_5X_Edited_API_25 [emulator-5554]
Application terminated.

Answer 1

试试这个

public class RevToolBar
{
Context mContext;
public RevToolBar(Context context){
    mContext = context;
  }
public Toolbar getRevToolbar() {
    Toolbar toolbar = new Toolbar(mContext);
    LinearLayout.LayoutParams toolBarParams = new LinearLayout.LayoutParams(
            Toolbar.LayoutParams.MATCH_PARENT,
            150
    );
    toolbar.setLayoutParams(toolBarParams);
    toolbar.setBackgroundColor(Color.BLUE);
    toolbar.setVisibility(View.VISIBLE);
    return toolbar;
   }
}

在MainActivity中

RevToolBar revToolBar = new RevToolBar(MainActivity.this);
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer .addView(revToolBar.getRevToolbar(), 0);