Question

第一次启动应用程序时，我会打开DialogFragment。用户选择一个值然后存储为首选项，然后listview根据所选值填充数据。

问题是我的自定义DialogFragment是一个内部类，在我的MainActivity中。我似乎无法在 onclick 中调用我的适配器（将listview加载数据）。

我试过在内部类中访问我的适配器函数但是我收到了“静态”引用错误。同时，我尝试在类中嵌入我的适配器函数，但结果相同：

无法对非静态方法进行静态引用

我玩弄了一些黑客，但我知道有更好的标准方法。任何帮助/建议将不胜感激。

我的代码如下所示。

public class MainActivity extends ListActivity {

private Cursor lines;
private MetroSleepDb db;
private ListAdapter adapter;
public static final String PREFS_NAME = "METROSLEEP_PREFS";
public static int PREFS_CITY = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
    boolean prefs_isset = settings.contains("DEFAULT_CITY");

    if(prefs_isset) {

        PREFS_CITY = settings.getInt("DEFAULT_CITY", 0);


    } else {

        chooseCityDialog();
        PREFS_CITY = settings.getInt("DEFAULT_CITY", 0);

    }

    Editor editor = settings.edit();
    editor.putInt("DEFAULT_CITY", PREFS_CITY);
    editor.commit();

}


public void setAdapters() {

    Toast.makeText(getApplicationContext(), "Preference set to: "+PREFS_CITY, Toast.LENGTH_LONG).show();

    db = new MetroSleepDb(this);
    lines = db.getLines(); // you would not typically call this on the main thread
    //ListView listView = (ListView) findViewById(R.id.li);
    adapter = new SimpleCursorAdapter(this, android.R.layout.simple_list_item_1, 
            lines, 
            new String[] {"line_id"}, 
            new int[] {android.R.id.text1}, 0);


    getListView().setAdapter(adapter);
    getListView().setOnItemClickListener(onAnswerClicked);

}


public String getItem(int pos) {

    Cursor c = (Cursor) adapter.getItem(pos);
    String value = c.getString(c.getColumnIndex("line_id"));
    return value;
}


private OnItemClickListener onAnswerClicked = new OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position,
            long id) {

        String line_value = getItem(position);
        Intent intent = new Intent(MainActivity.this, ChooseStations.class);
        intent.putExtra("line", line_value);
        startActivity(intent);
    }

};

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.activity_main, menu);
    return true;
}


@Override
public boolean onOptionsItemSelected(MenuItem  item) {
    switch (item.getItemId()) {
    case android.R.id.home:

        NavUtils.navigateUpFromSameTask(this);
        return true;

    case R.id.menu_settings:
        Intent intent = new Intent(this, SettingsActivity.class);
        startActivity(intent);
        return true;
    }
    return super.onOptionsItemSelected(item);
}

public void chooseCityDialog() {

    DialogFragment newFragment = new DialogSetup();
    newFragment.setCancelable(false);
    newFragment.setRetainInstance(true);
    newFragment.show(getFragmentManager(), "citypref");


}


public static final class DialogSetup extends DialogFragment {
    public Dialog onCreateDialog(Bundle savedInstanceState) {

        AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
        builder.setTitle(R.string.prompt_choose_city)
               .setCancelable(false) 
               .setInverseBackgroundForced(true)
               .setItems(R.array.Cities, new DialogInterface.OnClickListener() {
                   public void onClick(DialogInterface dialog, int which) {

                       PREFS_CITY = which;

               }
        });

        return builder.create();
    }

    @Override
    public void onDismiss(DialogInterface dialog) {
        // Do whatever
    }

}



@Override
protected void onStop(){
   super.onStop();

  SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
  SharedPreferences.Editor editor = settings.edit();
  //editor.putBoolean("silentMode", mSilentMode);

  settings.getInt("DEFAULT_CITY", PREFS_CITY);
  editor.commit();
}
}

Answer 1

我试过在内部类中访问我的适配器函数但是我收到“静态”引用错误。与此同时，我试过了在我的类中嵌入我的适配器函数，但结果是同样的：

在DialogFragment中，您已经显示了Activity的引用，其中显示了Dialog，您可以使用它来访问适配器：

public void onClick(DialogInterface dialog, int which) {
      PREFS_CITY = which;
      MainActivity ma = (MainActivity) getActivity();
      // create a getter method in the MainActivity to access the adapter 
      // or whatever else you need
}

如何在dialogfragment内部类中调用适配器

1 个答案: