安卓微调页脚

Question

有没有办法在微调器下拉列表中添加页脚？例如，假设我正在从数据库中填充微调器，但无论我如何排列列表，我都希望在列表底部进行选择。该列表可能是“数据库项目 1、2..、3...”，并且在列表底部的页脚选项是“将项目添加到数据库”。

到目前为止，我已经按如下方式使用了您的 CustomSpinner 类:

public class CustomSpinner extends Spinner implements OnItemClickListener {

private AlertDialog myDialog = null;
private OnClickListener myButtonClickListener = null;
private GrainSpinnerAdapter adapter = null;

public CustomSpinner(Context context, AttributeSet attrs) {
    super(context, attrs);
}

public void setButtonClickListener(OnClickListener listener) {
    myButtonClickListener = listener;
}

public void setAdapter(GrainSpinnerAdapter adapter){
    this.adapter = adapter;
}

@Override
public boolean performClick() {
    Context context = getContext();

    //Inflate the layout
    final LayoutInflater inflater = LayoutInflater.from(getContext());
    final View v = inflater.inflate(R.layout.my_custom_spinner, null);

    // set up list view
    final ListView lv = (ListView) v.findViewById(R.id.list);
    lv.setAdapter(adapter);
    lv.setSelection(getSelectedItemPosition());
    lv.setOnItemClickListener(this);

    // set up button
    final Button btn = (Button) v.findViewById(R.id.addButton);
    btn.setOnClickListener(myButtonClickListener);

    // build our dialog
    AlertDialog.Builder builder = new AlertDialog.Builder(context);

    // show prompt, just as our Spinner parent does
    if (getPrompt() != null) {
        builder.setTitle(getPrompt());
    }

    // create and show dialog
    myDialog = builder.setView(v).create();
    myDialog.show();

    return true;
}

@Override
public void onItemClick(AdapterView<?> view, View itemView, int position, long id) {
    setSelection(position);
    if (myDialog != null) {
        myDialog.dismiss();
        myDialog = null;
    }

}

}我想使用像这样的单独适配器:

public class GrainListAdapter extends SimpleCursorAdapter {

private static final String DEFAULT_UNITS = "American";
private Button upButton;
private Context myContext;
private RecipeGrainActivity parentActivity;
private Button downButton;
private String units;
private double getLbs;

public GrainListAdapter(Context context, int layout, Cursor c, String[] from, int[] to) {
    super(context, layout, c, from, to);
    myContext = context;
    parentActivity = (RecipeGrainActivity) myContext;

    //Checks for metric pref.
    SharedPreferences myPrefs = PreferenceManager.getDefaultSharedPreferences(context);
    units = String.valueOf(myPrefs.getString(context.getString(R.string.pref_measurement), DEFAULT_UNITS));
}

@Override
public void bindView(View view, Context context, Cursor cursor) {
    int idColumn = cursor.getColumnIndex("_id");
    final int getId = cursor.getInt(idColumn);
    final double increment = 0.25;

    UnitsConversions convert = new UnitsConversions();

    int nameColumn = cursor.getColumnIndex("name");
    String getName = cursor.getString(nameColumn);
    TextView name = (TextView)view.findViewById(R.id.GrainName);
    name.setText(getName);

    int originColumn = cursor.getColumnIndex("origin");
    String getOrigin = cursor.getString(originColumn);
    TextView origin = (TextView)view.findViewById(R.id.GrainOrigin);
    origin.setText(getOrigin);

    if(units.equals("Metric")){
        //Sets labels to metric.
        String kilos = context.getResources().getString (R.string.kilograms);
        TextView weightLabel = (TextView)view.findViewById(R.id.GrainLbsLabel);
        weightLabel.setText(kilos);
    }


}

@Override
public View newView(Context context, Cursor cursor, final ViewGroup parent) {
    View view = View.inflate(context, R.layout.grain_list_item, null);
    return view;
}

这允许我为微调器中的每个列表项构建一个自定义行。我在想我可以在我的 Activity 中使用 customspinner.setadapter() 将适配器设置为 CustomSpinner。但是，CustomSpinner 类中定义的 ListView 使用类中引用的适配器。如何将我的适配器传递给类以便它可以使用它？

这是我必须将自定义项目添加到我的布局中的方法:

<com.bluelightuniverse.android.brewmobile.CustomSpinner
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/GrainNameSpinner"
    android:layout_toRightOf="@id/GrainOriginSpinner"
    android:layout_toLeftOf="@+id/AddGrainButton">
</com.bluelightuniverse.android.brewmobile.CustomSpinner>

Answer 1

在您的 CursorAdapter 中，覆盖方法 getCount() 和 getDropDownView:例如，如果您想在末尾放置一个按钮，您可以这样做:

new SimpleCursorAdapter(...) {

        @Override
        public int getCount() {
            return super.getCount()+1;
        }

        @Override
        public View getDropDownView(int position, View convertView,
                ViewGroup parent) {
            View res=null;
            if (position == getCount()-1) {
                //better not try to reuse our view as it can be requested for the spinner or by the list with different kind of layouts.
                View mButton= getActivity().getLayoutInflater().inflate(R.layout.create_activity_button, parent,false);
                mButton.setOnClickListener(ObservationListFragment.this);
                res= mButton;
            } else if (convertView != null && android.R.id.button1 == convertView.getId() ){
             // If the adapter is trying to recycle our footer view, we force the generation of a new view (check on the id of our custom view)
                res= super.getDropDownView(position, null, parent);
            } else {
                res= super.getDropDownView(position, convertView, parent);
            }
            return res;
        }
    };