Question

我的项目名为＆＃34; NavigationDrawer＆＃34;并且意识到考虑到这个应用程序不仅仅有一个导航抽屉，它应该被更改并重命名为相关的东西。

我试图导入该项目，但它一直说没有找到源文件，所以我开始用老式的方式（复制并粘贴所有内容，确保我更改了包名等）。但是现在当我尝试运行该程序时，它说它无法找到MainActivity方法。它一直在说＆＃34; Class＆＃39; MainActivity＆＃39;永远不会被使用＆＃34;没有它，我的程序显然不会运行。

我知道我的智慧结束了哈哈，我知道我可能没有编辑其中一个文件或者其他东西，但是如果你能指出我的方向那么好。< / p>

我的代码：

package com.example.ColeraineTown;

imports....

public class MainActivity extends Activity {
private DrawerLayout DrawerLayout;
private ListView DrawerList;
private ActionBarDrawerToggle DrawerToggle;

private CharSequence DrawerTitle;
private CharSequence Title;
private String[] pageArray;

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

    Title = DrawerTitle = getTitle();
    pageArray = getResources().getStringArray(R.array.pageArray);
    DrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
    DrawerList = (ListView) findViewById(R.id.left_drawer);

    // set a custom shadow that overlays the main content when the drawer opens
    DrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);
    // set up the drawer's list view with items and click listener
    DrawerList.setAdapter(new ArrayAdapter<String>(this,
            R.layout.drawer_list_item, pageArray));
    DrawerList.setOnItemClickListener(new DrawerItemClickListener());

    // enable ActionBar app icon to behave as action to toggle nav drawer
    getActionBar().setDisplayHomeAsUpEnabled(true);
    getActionBar().setHomeButtonEnabled(true);

    // ActionBarDrawerToggle ties together the the proper interactions
    // between the sliding drawer and the action bar app icon
    DrawerToggle = new ActionBarDrawerToggle(
            this,                  /* host Activity */
            DrawerLayout,         /* DrawerLayout object */
            R.drawable.ic_drawer,  /* nav drawer image to replace standard image in action bar */
            R.string.drawer_open,  /* "open drawer" description for accessibility */
            R.string.drawer_close  /* "close drawer" description for accessibility */
    ) {
        public void onDrawerClosed(View view) {
            getActionBar().setTitle(Title);
            invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
        }

        public void onDrawerOpened(View drawerView) {
            getActionBar().setTitle(DrawerTitle);
            invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()
        }
    };
    DrawerLayout.setDrawerListener(DrawerToggle);

    if (savedInstanceState == null) {
        selectItem(0);
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.main, menu);
    return super.onCreateOptionsMenu(menu);
}

/* Called whenever we call invalidateOptionsMenu() */
@Override
public boolean onPrepareOptionsMenu(Menu menu) {
    // If the nav drawer is open, hide action items related to the content view
    boolean drawerOpen = DrawerLayout.isDrawerOpen(DrawerList);
    menu.findItem(R.id.action_websearch).setVisible(!drawerOpen);
    return super.onPrepareOptionsMenu(menu);
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // The action bar home/up action should open or close the drawer.
    // ActionBarDrawerToggle will take care of this.
    if (DrawerToggle.onOptionsItemSelected(item)) {
        return true;
    }
    // Handle action buttons
    switch(item.getItemId()) {
        case R.id.action_websearch:
            // create intent to perform web search for this planet
            Intent intent = new Intent(Intent.ACTION_WEB_SEARCH);
            intent.putExtra(SearchManager.QUERY, getActionBar().getTitle());
            // catch event that there's no activity to handle intent
            if (intent.resolveActivity(getPackageManager()) != null) {
                startActivity(intent);
            } else {
                Toast.makeText(this, R.string.app_not_available, Toast.LENGTH_LONG).show();
            }
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

/* The click listener for ListView in the navigation drawer */
private class DrawerItemClickListener implements ListView.OnItemClickListener {
    @Override
    public void onItemClick(AdapterView parent, View view, int position, long id) {
        selectItem(position);
    }
}

private void selectItem(int position) {
    // update the main content by replacing fragments
    Fragment fragment = new PageFragment();
    Bundle args = new Bundle();
    args.putInt(PageFragment.ARG_PAGE_NUMBER, position);
    fragment.setArguments(args);



    FragmentManager fragmentManager = getFragmentManager();
    fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit();

    // update selected item and title, then close the drawer
    DrawerList.setItemChecked(position, true);
    setTitle(pageArray[position]);
    DrawerLayout.closeDrawer(DrawerList);
}

@Override
public void setTitle(CharSequence title) {
    Title = title;
    getActionBar().setTitle(Title);
}

/**
 * When using the ActionBarDrawerToggle, you must call it during
 * onPostCreate() and onConfigurationChanged()...
 */

@Override
protected void onPostCreate(Bundle savedInstanceState) {
    super.onPostCreate(savedInstanceState);
    // Sync the toggle state after onRestoreInstanceState has occurred.
    DrawerToggle.syncState();
}

@Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);
    // Pass any configuration change to the drawer toggls
    DrawerToggle.onConfigurationChanged(newConfig);
}

/**
 * Fragment that appears in the "content_frame", shows a planet
 */
public static class PageFragment extends Fragment {
    public static final String ARG_PAGE_NUMBER = "page_number";

    public PageFragment() {
        // Empty constructor required for fragment subclasses
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_planet, container, false);
        int pgNum = getArguments().getInt(ARG_PAGE_NUMBER);
        String page = getResources().getStringArray(R.array.pageArray)[pgNum];

        int imageId = getResources().getIdentifier(page.toLowerCase(Locale.getDefault()),
                "drawable", getActivity().getPackageName());
        ((ImageView) rootView.findViewById(R.id.image)).setImageResource(imageId);
        getActivity().setTitle(page);
        return rootView;
    }
}

}

Answer 1

您应该在Android Manifest中为该项目声明它。

<activity android:name="com.example.ColeraineTown.MainActivity">
    <intent-filter>
        <action android:name="android.intent.action.MAIN"/>
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>

More docs

从未调用过主类

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