尽管isClickable（）为true，但按钮不可单击

Question

我有一个填充有项目的ListView，其中一些包含Button。有时，Buttons onClick（）正确注册，但其他时候，onClick（）根本不起作用。我正在检查isClickable（）是否为true，并且在所有情况下都是如此。为什么Button可以将isClickable（）设置为true，但仍不注册onClick（）的可能原因是什么？

编辑：这是我的适配器的getView（）

public View getView(int position, View convertView, ViewGroup parent) {
    final ExpandableListItem object = mData.get(position);
    final View view = storedViews.get(position);

    if (object instanceof FillerParamListItem) {
        return view;
    }

    //Load the holder
    ExpandingViewHolder holder = (ExpandingViewHolder) view.getTag();

    //Handle collapsing and expanding the cells
    if (((ParameterActivity) activity).listView.isExpanded() && !object.isExpanded()) {
        view.setAlpha(.20f);
    } else {
        view.setAlpha(1f);
    }

    if (object instanceof SwitchParamListItem) {
       ....
    } else if (object instanceof DomainListItem) {
       ....
    } else if (object instanceof ParameterListItem) {
        if (((ParameterActivity) activity).listView.isExpanded() && !object.isExpanded()) {
            holder.expandingLayout.setVisibility(View.GONE);
            holder.valueTextView.setVisibility(View.VISIBLE);

            if (activity.getCoreApplication().getOfflineMode()) {
                holder.collapsedLayout.setBackground(activity.getResources().getDrawable(R.drawable.main_list_item_background_offline));
            } else {
                holder.collapsedLayout.setBackground(activity.getResources().getDrawable(R.drawable.main_list_item_background));
            }

            holder.collapsedLayout.setElevation(0);
        } else {
            if (object.isExpanded()) {
                System.out.println("expanded parameter item");

                holder.expandingLayout.setVisibility(View.VISIBLE);
                holder.valueTextView.setVisibility(View.GONE);
                holder.valueEditText.setVisibility(View.VISIBLE);

                if (activity.getCoreApplication().getOfflineMode()) {
                    holder.expandingLayout.setBackground(activity.getResources().getDrawable(R.drawable.parameter_activity_expanded_layout_background_offline));
                    holder.collapsedLayout.setBackground(activity.getResources().getDrawable(R.drawable.parameter_activity_expanded_layout_background_offline));
                } else {
                    holder.expandingLayout.setBackground(activity.getResources().getDrawable(R.drawable.parameter_activity_expanded_layout_background));
                    holder.collapsedLayout.setBackground(activity.getResources().getDrawable(R.drawable.parameter_activity_expanded_layout_background));
                }

                holder.collapsedLayout.setElevation(3.0f * activity.getResources().getDisplayMetrics().density);

            } else {
                holder.expandingLayout.setVisibility(View.GONE);
                holder.valueTextView.setVisibility(View.VISIBLE);
                holder.valueEditText.setVisibility(View.INVISIBLE);

                if (activity.getCoreApplication().getOfflineMode()) {
                    holder.collapsedLayout.setBackground(activity.getResources().getDrawable(R.drawable.main_list_item_background_offline));
                } else {
                    holder.collapsedLayout.setBackground(activity.getResources().getDrawable(R.drawable.main_list_item_background));
                }

                holder.collapsedLayout.setElevation(0);
            }
        }

        if (object.getImgResource() != ExpandableListItem.NO_ICON) {
            holder.imageView.setImageBitmap(object.getImage());
        } else {
            holder.imageView.setVisibility(View.INVISIBLE);
        }

        holder.titleTextView.setText(object.name);
        holder.valueTextView.setText(object.getValue());
        holder.unitTextView.setText(object.unitSym);

        holder.descriptionTextView.setText(object.description);
        holder.useTextView.setText(object.hint);

        ParameterListItem parameterListItem = (ParameterListItem) object;

        //Register listeners for the seeker bar and EditText for this specific parameter
        TextListener editTextListener = new TextListener(parameterListItem, activity, view, holder.valueEditText);
        holder.seekbar.setOnSeekBarChangeListener(parameterListItem.getListener());
        holder.valueEditText.addTextChangedListener(editTextListener);
        parameterListItem.registerTextListener(editTextListener);
        holder.valueEditText.setOnEditorActionListener(editTextListener);
        parameterListItem.registerSeekBar(holder.seekbar);

        holder.valueEditText.setTag("PROGRAM");
        holder.valueEditText.setText(object.getValue());

        //show value and symbols within the expanded cells for the seeker bar track
        holder.minValueTextView.setText(Util.getStringForFloat(parameterListItem.getMinValue()) + object.unitSym);
        holder.maxValueTextView.setText(Util.getStringForFloat(parameterListItem.getMaxValue()) + object.unitSym);
        holder.middleValueTextView.setText(Util.getStringForFloat((parameterListItem.getMaxValue() + parameterListItem.getMinValue()) / 2) + object.unitSym);

        view.setOnTouchListener(editTextListener);
    }

    object.assocView = view;

    return view;
}

，这里是XML（我现在仅包括按钮部分）。这里的RelativeLayout包含在“适配器中的expandingLayout”中：

<RelativeLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"

        android:layout_below="@id/parameter_activity_parameter_use_layout"

        android:layout_marginTop="20dp"

        android:orientation="horizontal"

        android:background="@android:color/transparent">

        <Button
            android:id="@+id/parameter_activity_parameter_cancel_button"
            android:layout_height="wrap_content"
            android:layout_width="wrap_content"

            android:layout_alignParentStart="true"
            android:layout_marginLeft="10dp"

            android:onClick="cancelClicked"
            android:clickable="true"

            android:background="?android:attr/selectableItemBackground"

            android:text="Cancel"
            android:textColor="@color/button_text_color"
            android:textSize="21sp"
            android:textStyle="bold"/>

        <Button
            android:id="@+id/parameter_activity_parameter_undo_button"
            android:layout_height="wrap_content"
            android:layout_width = "wrap_content"

            android:layout_centerHorizontal="true"

            android:clickable="true"
            android:onClick="undoClicked"

            android:background="?android:attr/selectableItemBackground"

            android:text="Undo Last Change"
            android:textColor="@color/button_text_color"
            android:textSize="21sp"
            android:textStyle="bold"/>

        <Button
            android:id="@+id/parameter_activity_parameter_apply_button"
            android:layout_height="wrap_content"
            android:layout_width="wrap_content"

            android:layout_alignParentEnd="true"

            android:layout_marginRight="10dp"

            android:clickable="true"
            android:onClick="applyClicked"

            android:background="?android:attr/selectableItemBackground"

            android:text="Apply"
            android:textColor="@color/button_text_color"
            android:textSize="21sp"
            android:textStyle="bold" />
    </RelativeLayout>