Question

我有一个已为上下文菜单注册的列表视图。对于列表中的某些项目，上下文菜单不适用。在这些情况下，我只是不在onCreateContextMenu方法中夸大菜单。

不幸的是，这意味着当不显示上下文菜单的项目被长按Android时，会将其作为短按处理（可能是因为上下文菜单通常会返回true表示长按事件已经过处理）。

这导致listview中的行为不一致 - 某些项目在您长按单击时显示上下文菜单 - 其他项目则不显示，然后执行默认单击行为。如何确保即使不显示上下文菜单的项目也会消耗长按，以便不调用onItemClick方法？

@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo) {

  AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) menuInfo;
  Playable playable = (Playable) info.targetView.getTag(R.id.playable);
  if (playable != null && !(playable instanceof AutoRadioStation) && !(playable.getId().equals(Playlist.AUTOMATIC_PLAYLIST))) {
    v.setTag(R.id.playable, playable); // This copies the tag so that it is contained within the view used for the menu.
    Drawable stationImage = (Drawable) ((ImageView) info.targetView.findViewById(R.id.artwork)).getDrawable().getConstantState().newDrawable();

    menu.setHeaderTitle(playable.getName());
    menu.setHeaderIcon(stationImage);
    MenuInflater inflater = getActivity().getMenuInflater();
    inflater.inflate(R.menu.saved_context_menu, menu);
  }
}

Answer 1

我遇到了类似的问题，最后我使用的是Dialog而不是上下文菜单。

我的活动实施OnItemLongClickListener，如果条件满足，我会从onLongItemClick()展示。

Answer 2

我终于开始实施一个版本的NathanZ解决方案了。关于将contextMenu转换为DialogFragment似乎没有太多东西，所以我会在这里粘贴我的大部分解决方案。

实现onLongItemClick侦听器也意味着我能够在listview中有一个不需要菜单的长按事件。不幸的是因为你无法将菜单传递给对话框，我不得不重复使用现有的ListViewElement类型来为listview中的每个“menu”项存储id和文本字符串。

  @Override
  public boolean onItemLongClick(AdapterView<?> parent, View view, int item, long position) {

    Playable playable = (Playable) view.getTag(R.id.playable);
    //Switch haptic feedback off by default so if we don't handle the long click we don't vibrate
    parent.setHapticFeedbackEnabled(false);

    if (playable == null) {
      // This must be a message bar so the only option is to update all saved content
      updateAll();
      parent.setHapticFeedbackEnabled(true);
    } else {
      if (!(playable instanceof AutoRadioStation) && !(playable.getId().equals(Playlist.AUTOMATIC_PLAYLIST))) {
        Drawable drawable = (Drawable) ((ImageView) view.findViewById(R.id.artwork)).getDrawable().getConstantState().newDrawable();
        showContextDialog(playable, drawable);
        parent.setHapticFeedbackEnabled(true);
      }
    }
    return true;
  }
  private void showContextDialog(Playable playable, Drawable drawable) {
    FragmentManager fm = getActivity().getSupportFragmentManager();
    final List<ListViewElement> array = new ArrayList<ListViewElement>();
    array.add(new ListViewElement(R.id.menu_share, null, getString(R.string.share), true));
    array.add(new ListViewElement(R.id.menu_delete, null, getString(R.string.delete), true));
    ContextMenuDialog dialog = new ContextMenuDialog(drawable, playable.getName(), array, playable);
    dialog.setOnItemClickListener(this);
    dialog.show(fm, "Context Menu");
  }

  //Callback from the ContextMenuDialog class
  @Override
  public void onItemClickDialogFragment(int option, Playable playable) {
    switch (option) {
      case R.id.menu_delete :
        // Perform delete actions
        break;
      case R.id.menu_share :
        // Perform share actions
        break;
    }
  }


public class ContextMenuDialog extends DialogFragment implements OnItemClickListener {

  private Drawable drawableIcon;
  private String title;
  private List<ListViewElement> values;
  private Playable playable;
  private DialogFragmentOnItemClickListener listener;

  public interface DialogFragmentOnItemClickListener {
    void onItemClickDialogFragment(int option, Playable playable);
  }

  public void setOnItemClickListener(DialogFragmentOnItemClickListener listener) {
    this.listener = listener;
  }

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    //Create the dialog without a title since the layout includes a customized title
    setStyle(DialogFragment.STYLE_NO_TITLE, R.style.MyDialogStyle);
  }

  public ContextMenuDialog(Drawable drawableIcon, String title, List<ListViewElement> values, Playable playable) {
    this.drawableIcon = drawableIcon;
    this.title = title;
    this.values = values;
    this.playable = playable;
  }


  public ContextMenuDialog(int drawableResource, String title, List<ListViewElement> values, Playable playable) {
    this.drawableIcon = getResources().getDrawable(drawableResource);
    this.title = title;
    this.values = values;
    this.playable = playable;
  }

  @Override
  public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.context_menu, container, true);
    TextView titleView = (TextView) view.findViewById(R.id.context_menu_title);
    titleView.setText(title);
    ImageView icon = (ImageView) view.findViewById(R.id.context_menu_artwork);
    icon.setImageDrawable(drawableIcon);

    ListView listView = (ListView) view.findViewById(R.id.context_menu_listview);
    ContextMenuAdapter adapter = new ContextMenuAdapter(getActivity(), R.layout.context_menu_list_item, values);
    listView.setAdapter(adapter);
    listView.setOnItemClickListener(this);
    return view;
 }

如果没有显示上下文菜单，如何在短暂点击时停止长按

2 个答案: