Question

我试图在Action Bar Compat中构建一个下拉菜单，根据开发示例：http://developer.android.com/guide/topics/ui/actionbar.html#Dropdown

我无法通过onNavigationItemSelected来解雇。

正在生成操作栏中的微调器下拉项目，位于操作栏标题的右侧。当我按下它时，我看到三角形图标变为蓝色。 OnNreigationListener和Sting []字符串正在OnCreate中运行。

我怎样才能让它发挥作用？

public class Main extends ActionBarActivity {

    private ActionBar actionBar;

    @Override
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        actionBar = getActionBar();
        actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_LIST);

        spinner = new Spinner(this);
        SpinnerAdapter mSpinnerAdapter = ArrayAdapter.createFromResource(this,
                R.array.operating_systems, android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(mSpinnerAdapter);

        ActionBar.OnNavigationListener mOnNavigationListener = new ActionBar.OnNavigationListener() {
            String[] strings = getResources().getStringArray(R.array.operating_systems);

            @Override
            public boolean onNavigationItemSelected(int position, long itemId) {
                ListContentFragment newFragment = new ListContentFragment();
                FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
                ft.replace(R.id.fragment_container, newFragment, strings[position]);
                ft.commit();

                return true;
            }
        };
    }

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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.action_share:
                Toast.makeText(this, "Refresh selected", Toast.LENGTH_SHORT)
                        .show();
                break;
            case R.id.action_settings:
                Toast.makeText(this, "Settings selected", Toast.LENGTH_SHORT)
                        .show();
                break;
            default:
                break;
        }
        return true;
    }

}

Answer 1

看起来你没有打电话给ActionBar.setListNavigationCallbacks。

示例中的第4步：

使用setListNavigationCallbacks（）设置下拉列表的回调。例如：

actionBar.setListNavigationCallbacks(mSpinnerAdapter, mNavigationCallback);

onNavigationItemSelected从未在Actionbar的微调器上调用

1 个答案: