private int buildDropDown() { ViewGroup dropDownView; int otherHeights = 0; if (mDropDownList == null) { Context context = mContext; mDropDownList = new DropDownListView(context, !mModal); if (mDropDownListHighlight != null) { mDropDownList.setSelector(mDropDownListHighlight); } mDropDownList.setAdapter(mAdapter); mDropDownList.setOnItemClickListener(mItemClickListener); mDropDownList.setFocusable(true); mDropDownList.setFocusableInTouchMode(true); mDropDownList.setOnItemSelectedListener( new AdapterView.OnItemSelectedListener() { public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { if (position != -1) { DropDownListView dropDownList = mDropDownList; if (dropDownList != null) { dropDownList.mListSelectionHidden = false; } } } public void onNothingSelected(AdapterView<?> parent) {} }); mDropDownList.setOnScrollListener(mScrollListener); if (mItemSelectedListener != null) { mDropDownList.setOnItemSelectedListener(mItemSelectedListener); } dropDownView = mDropDownList; View hintView = mPromptView; if (hintView != null) { // if an hint has been specified, we accomodate more space for it and // add a text view in the drop down menu, at the bottom of the list LinearLayout hintContainer = new LinearLayout(context); hintContainer.setOrientation(LinearLayout.VERTICAL); LinearLayout.LayoutParams hintParams = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 0, 1.0f); switch (mPromptPosition) { case POSITION_PROMPT_BELOW: hintContainer.addView(dropDownView, hintParams); hintContainer.addView(hintView); break; case POSITION_PROMPT_ABOVE: hintContainer.addView(hintView); hintContainer.addView(dropDownView, hintParams); break; default: break; } // measure the hint's height to find how much more vertical space // we need to add to the drop down's height int widthSpec = MeasureSpec.makeMeasureSpec(mDropDownWidth, MeasureSpec.AT_MOST); int heightSpec = MeasureSpec.UNSPECIFIED; hintView.measure(widthSpec, heightSpec); hintParams = (LinearLayout.LayoutParams) hintView.getLayoutParams(); otherHeights = hintView.getMeasuredHeight() + hintParams.topMargin + hintParams.bottomMargin; dropDownView = hintContainer; } mPopup.setContentView(dropDownView); } else { dropDownView = (ViewGroup) mPopup.getContentView(); final View view = mPromptView; if (view != null) { LinearLayout.LayoutParams hintParams = (LinearLayout.LayoutParams) view.getLayoutParams(); otherHeights = view.getMeasuredHeight() + hintParams.topMargin + hintParams.bottomMargin; } } // getMaxAvailableHeight() subtracts the padding, so we put it back // to get the available height for the whole window int padding = 0; Drawable background = mPopup.getBackground(); if (background != null) { background.getPadding(mTempRect); padding = mTempRect.top + mTempRect.bottom; // If we don't have an explicit vertical offset, determine one from the window // background so that content will line up. if (!mDropDownVerticalOffsetSet) { mDropDownVerticalOffset = -mTempRect.top; } } // Max height available on the screen for a popup. boolean ignoreBottomDecorations = mPopup.getInputMethodMode() == PopupWindow.INPUT_METHOD_NOT_NEEDED; final int maxHeight = /*mPopup.*/ getMaxAvailableHeight( mDropDownAnchorView, mDropDownVerticalOffset, ignoreBottomDecorations); if (mDropDownHeight == ViewGroup.LayoutParams.MATCH_PARENT) { return maxHeight + padding; } final int listContent = /*mDropDownList.*/ measureHeightOfChildren( MeasureSpec.UNSPECIFIED, 0, -1 /*ListView.NO_POSITION*/, maxHeight - otherHeights, -1); // add padding only if the list has items in it, that way we don't show // the popup if it is not needed if (listContent > 0) otherHeights += padding; return listContent + otherHeights; }