Question

我是android新手，我正在尝试按照Android网站上的教程https://developer.android.com/training/implementing-navigation/nav-drawer.html制作导航抽屉。

在本教程中，他们使用ListView初始化变量，并在另一个类中使用该变量。他们是如何实现这一目标的？谢谢你的帮助

代码来自链接：

public class MainActivity extends Activity {
    private String[] mPlanetTitles;
    private DrawerLayout mDrawerLayout;
    private ListView mDrawerList;
    ...

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

        mPlanetTitles = getResources().getStringArray(R.array.planets_array);
        mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
        mDrawerList = (ListView) findViewById(R.id.left_drawer);

        // Set the adapter for the list view
        mDrawerList.setAdapter(new ArrayAdapter<String>(this,
                R.layout.drawer_list_item, mPlanetTitles));
        // Set the list's click listener
        mDrawerList.setOnItemClickListener(new DrawerItemClickListener());

        ...
    }
}

抽屉听众

    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) {
 // Highlight the selected item, update the title, and close the drawer
    mDrawerList.setItemChecked(position, true);
    setTitle(mPlanetTitles[position]);
    mDrawerLayout.closeDrawer(mDrawerList);
}


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

我的代码：

主要活动在这里：

public class MainActivity extends Activity {
    private String[] arrayPlanets;
    private DrawerLayout mDrawerLayout;
    public ListView mDrawerPlanetList;

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

        arrayPlanets = getResources().getStringArray(R.array.planets);
        mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
        mDrawerPlanetList = (ListView) findViewById(R.id.list_planets);

        mDrawerPlanetList.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,arrayPlanets));
        mDrawerPlanetList.setOnItemClickListener(new DrawerItemClickListener());
    }

抽屉听众在这里：

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){
        mDrawerPlanetList.setItemChecked(position, true);
        aetTitle(arrayPlanets[position]);
        mDrawerLayout.closeDrawer(mDrawerPlanetList);
    }


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

Answer 1

您可以将listview设为public，并在包含该列表视图的mainActivity打开的另一个类上访问它。对于片段：((MainActivity)getActivity()).myListView

从Android Studio中的MainActivity访问变量

1 个答案: