Beginnings of a pre-HC dropdown Spinner

IcsAbsSpinner.java

/*
 * Copyright (C) 2006 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.actionbarsherlock.internal.widget;

import android.content.Context;
import android.content.res.TypedArray;
import android.database.DataSetObserver;
import android.graphics.Rect;
import android.os.Parcel;
import android.os.Parcelable;
import android.util.AttributeSet;
import android.util.SparseArray;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.SpinnerAdapter;

/**
 * An abstract base class for spinner widgets. SDK users will probably not
 * need to use this class.
 * 
 * @attr ref android.R.styleable#AbsSpinner_entries
 */
public abstract class IcsAbsSpinner extends AdapterView<SpinnerAdapter> {
    SpinnerAdapter mAdapter;

    int mHeightMeasureSpec;
    int mWidthMeasureSpec;
    boolean mBlockLayoutRequests;

    int mSelectionLeftPadding = 0;
    int mSelectionTopPadding = 0;
    int mSelectionRightPadding = 0;
    int mSelectionBottomPadding = 0;
    final Rect mSpinnerPadding = new Rect();

    final RecycleBin mRecycler = new RecycleBin();
    private DataSetObserver mDataSetObserver;

    /** Temporary frame to hold a child View's frame rectangle */
    private Rect mTouchFrame;

    public IcsAbsSpinner(Context context) {
        super(context);
        initAbsSpinner();
    }

    public IcsAbsSpinner(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public IcsAbsSpinner(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        initAbsSpinner();

        TypedArray a = context.obtainStyledAttributes(attrs,
                com.android.internal.R.styleable.AbsSpinner, defStyle, 0);

        CharSequence[] entries = a.getTextArray(R.styleable.AbsSpinner_entries);
        if (entries != null) {
            ArrayAdapter<CharSequence> adapter =
                    new ArrayAdapter<CharSequence>(context,
                            R.layout.simple_spinner_item, entries);
            adapter.setDropDownViewResource(R.layout.simple_spinner_dropdown_item);
            setAdapter(adapter);
        }

        a.recycle();
    }

    /**
     * Common code for different constructor flavors
     */
    private void initAbsSpinner() {
        setFocusable(true);
        setWillNotDraw(false);
    }

    /**
     * The Adapter is used to provide the data which backs this Spinner.
     * It also provides methods to transform spinner items based on their position
     * relative to the selected item.
     * @param adapter The SpinnerAdapter to use for this Spinner
     */
    @Override
    public void setAdapter(SpinnerAdapter adapter) {
        if (null != mAdapter) {
            mAdapter.unregisterDataSetObserver(mDataSetObserver);
            resetList();
        }
        
        mAdapter = adapter;
        
        mOldSelectedPosition = INVALID_POSITION;
        mOldSelectedRowId = INVALID_ROW_ID;
        
        if (mAdapter != null) {
            mOldItemCount = mItemCount;
            mItemCount = mAdapter.getCount();
            checkFocus();

            mDataSetObserver = new AdapterDataSetObserver();
            mAdapter.registerDataSetObserver(mDataSetObserver);

            int position = mItemCount > 0 ? 0 : INVALID_POSITION;

            setSelectedPositionInt(position);
            setNextSelectedPositionInt(position);
            
            if (mItemCount == 0) {
                // Nothing selected
                checkSelectionChanged();
            }
            
        } else {
            checkFocus();            
            resetList();
            // Nothing selected
            checkSelectionChanged();
        }

        requestLayout();
    }

    /**
     * Clear out all children from the list
     */
    void resetList() {
        mDataChanged = false;
        mNeedSync = false;
        
        removeAllViewsInLayout();
        mOldSelectedPosition = INVALID_POSITION;
        mOldSelectedRowId = INVALID_ROW_ID;
        
        setSelectedPositionInt(INVALID_POSITION);
        setNextSelectedPositionInt(INVALID_POSITION);
        invalidate();
    }

    /** 
     * @see android.view.View#measure(int, int)
     * 
     * Figure out the dimensions of this Spinner. The width comes from
     * the widthMeasureSpec as Spinnners can't have their width set to
     * UNSPECIFIED. The height is based on the height of the selected item
     * plus padding. 
     */
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        int widthSize;
        int heightSize;

        int mPaddingLeft = getPaddingLeft();
        int mPaddingTop = getPaddingTop();
        int mPaddingRight = getPaddingRight();
        int mPaddingBottom = getPaddingBottom();
        mSpinnerPadding.left = mPaddingLeft > mSelectionLeftPadding ? mPaddingLeft
                : mSelectionLeftPadding;
        mSpinnerPadding.top = mPaddingTop > mSelectionTopPadding ? mPaddingTop
                : mSelectionTopPadding;
        mSpinnerPadding.right = mPaddingRight > mSelectionRightPadding ? mPaddingRight
                : mSelectionRightPadding;
        mSpinnerPadding.bottom = mPaddingBottom > mSelectionBottomPadding ? mPaddingBottom
                : mSelectionBottomPadding;

        if (mDataChanged) {
            handleDataChanged();
        }
        
        int preferredHeight = 0;
        int preferredWidth = 0;
        boolean needsMeasuring = true;
        
        int selectedPosition = getSelectedItemPosition();
        if (selectedPosition >= 0 && mAdapter != null && selectedPosition < mAdapter.getCount()) {
            // Try looking in the recycler. (Maybe we were measured once already)
            View view = mRecycler.get(selectedPosition);
            if (view == null) {
                // Make a new one
                view = mAdapter.getView(selectedPosition, null, this);
            }

            if (view != null) {
                // Put in recycler for re-measuring and/or layout
                mRecycler.put(selectedPosition, view);
            }

            if (view != null) {
                if (view.getLayoutParams() == null) {
                    mBlockLayoutRequests = true;
                    view.setLayoutParams(generateDefaultLayoutParams());
                    mBlockLayoutRequests = false;
                }
                measureChild(view, widthMeasureSpec, heightMeasureSpec);
                
                preferredHeight = getChildHeight(view) + mSpinnerPadding.top + mSpinnerPadding.bottom;
                preferredWidth = getChildWidth(view) + mSpinnerPadding.left + mSpinnerPadding.right;
                
                needsMeasuring = false;
            }
        }
        
        if (needsMeasuring) {
            // No views -- just use padding
            preferredHeight = mSpinnerPadding.top + mSpinnerPadding.bottom;
            if (widthMode == MeasureSpec.UNSPECIFIED) {
                preferredWidth = mSpinnerPadding.left + mSpinnerPadding.right;
            }
        }

        preferredHeight = Math.max(preferredHeight, getSuggestedMinimumHeight());
        preferredWidth = Math.max(preferredWidth, getSuggestedMinimumWidth());

        heightSize = resolveSizeAndState(preferredHeight, heightMeasureSpec, 0);
        widthSize = resolveSizeAndState(preferredWidth, widthMeasureSpec, 0);

        setMeasuredDimension(widthSize, heightSize);
        mHeightMeasureSpec = heightMeasureSpec;
        mWidthMeasureSpec = widthMeasureSpec;
    }

    int getChildHeight(View child) {
        return child.getMeasuredHeight();
    }
    
    int getChildWidth(View child) {
        return child.getMeasuredWidth();
    }
    
    @Override
    protected ViewGroup.LayoutParams generateDefaultLayoutParams() {
        return new ViewGroup.LayoutParams(
                ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.WRAP_CONTENT);
    }
    
    void recycleAllViews() {
        final int childCount = getChildCount();
        final IcsAbsSpinner.RecycleBin recycleBin = mRecycler;
        final int position = mFirstPosition;

        // All views go in recycler
        for (int i = 0; i < childCount; i++) {
            View v = getChildAt(i);
            int index = position + i;
            recycleBin.put(index, v);
        }  
    }

    /**
     * Jump directly to a specific item in the adapter data.
     */
    public void setSelection(int position, boolean animate) {
        // Animate only if requested position is already on screen somewhere
        boolean shouldAnimate = animate && mFirstPosition <= position &&
                position <= mFirstPosition + getChildCount() - 1;
        setSelectionInt(position, shouldAnimate);
    }

    @Override
    public void setSelection(int position) {
        setNextSelectedPositionInt(position);
        requestLayout();
        invalidate();
    }
    

    /**
     * Makes the item at the supplied position selected.
     * 
     * @param position Position to select
     * @param animate Should the transition be animated
     * 
     */
    void setSelectionInt(int position, boolean animate) {
        if (position != mOldSelectedPosition) {
            mBlockLayoutRequests = true;
            int delta  = position - mSelectedPosition;
            setNextSelectedPositionInt(position);
            layout(delta, animate);
            mBlockLayoutRequests = false;
        }
    }

    abstract void layout(int delta, boolean animate);

    @Override
    public View getSelectedView() {
        int mSelectedPosition = getSelectedItemPosition();
        int mItemCount = getAdapter().getCount();
        if (mItemCount > 0 && mSelectedPosition >= 0) {
            return getChildAt(mSelectedPosition - mFirstPosition);
        } else {
            return null;
        }
    }
   
    /**
     * Override to prevent spamming ourselves with layout requests
     * as we place views
     * 
     * @see android.view.View#requestLayout()
     */
    @Override
    public void requestLayout() {
        if (!mBlockLayoutRequests) {
            super.requestLayout();
        }
    }

    @Override
    public SpinnerAdapter getAdapter() {
        return mAdapter;
    }

    @Override
    public int getCount() {
        return getAdapter().getCount();
    }

    /**
     * Maps a point to a position in the list.
     * 
     * @param x X in local coordinate
     * @param y Y in local coordinate
     * @return The position of the item which contains the specified point, or
     *         {@link #INVALID_POSITION} if the point does not intersect an item.
     */
    public int pointToPosition(int x, int y) {
        Rect frame = mTouchFrame;
        if (frame == null) {
            mTouchFrame = new Rect();
            frame = mTouchFrame;
        }

        final int count = getChildCount();
        for (int i = count - 1; i >= 0; i--) {
            View child = getChildAt(i);
            if (child.getVisibility() == View.VISIBLE) {
                child.getHitRect(frame);
                if (frame.contains(x, y)) {
                    return mFirstPosition + i;
                }
            }
        } 
        return INVALID_POSITION;
    }
    
    static class SavedState extends BaseSavedState {
        long selectedId;
        int position;

        /**
         * Constructor called from {@link AbsSpinner#onSaveInstanceState()}
         */
        SavedState(Parcelable superState) {
            super(superState);
        }
        
        /**
         * Constructor called from {@link #CREATOR}
         */
        private SavedState(Parcel in) {
            super(in);
            selectedId = in.readLong();
            position = in.readInt();
        }

        @Override
        public void writeToParcel(Parcel out, int flags) {
            super.writeToParcel(out, flags);
            out.writeLong(selectedId);
            out.writeInt(position);
        }

        @Override
        public String toString() {
            return "AbsSpinner.SavedState{"
                    + Integer.toHexString(System.identityHashCode(this))
                    + " selectedId=" + selectedId
                    + " position=" + position + "}";
        }

        public static final Parcelable.Creator<SavedState> CREATOR
                = new Parcelable.Creator<SavedState>() {
            public SavedState createFromParcel(Parcel in) {
                return new SavedState(in);
            }

            public SavedState[] newArray(int size) {
                return new SavedState[size];
            }
        };
    }

    @Override
    public Parcelable onSaveInstanceState() {
        Parcelable superState = super.onSaveInstanceState();
        SavedState ss = new SavedState(superState);
        ss.selectedId = getSelectedItemId();
        if (ss.selectedId >= 0) {
            ss.position = getSelectedItemPosition();
        } else {
            ss.position = INVALID_POSITION;
        }
        return ss;
    }

    @Override
    public void onRestoreInstanceState(Parcelable state) {
        SavedState ss = (SavedState) state;
  
        super.onRestoreInstanceState(ss.getSuperState());

        if (ss.selectedId >= 0) {
            mDataChanged = true;
            mNeedSync = true;
            mSyncRowId = ss.selectedId;
            mSyncPosition = ss.position;
            mSyncMode = SYNC_SELECTED_POSITION;
            requestLayout();
        }
    }

    class RecycleBin {
        private final SparseArray<View> mScrapHeap = new SparseArray<View>();

        public void put(int position, View v) {
            mScrapHeap.put(position, v);
        }
        
        View get(int position) {
            // System.out.print("Looking for " + position);
            View result = mScrapHeap.get(position);
            if (result != null) {
                // System.out.println(" HIT");
                mScrapHeap.delete(position);
            } else {
                // System.out.println(" MISS");
            }
            return result;
        }

        void clear() {
            final SparseArray<View> scrapHeap = mScrapHeap;
            final int count = scrapHeap.size();
            for (int i = 0; i < count; i++) {
                final View view = scrapHeap.valueAt(i);
                if (view != null) {
                    removeDetachedView(view, true);
                }
            }
            scrapHeap.clear();
        }
    }
}

IcsSpinner.java

/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.actionbarsherlock.internal.widget;

import static android.view.ViewGroup.LayoutParams.MATCH_PARENT;
import static android.view.ViewGroup.LayoutParams.WRAP_CONTENT;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.content.res.TypedArray;
import android.database.DataSetObserver;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ListAdapter;
import android.widget.ListPopupWindow;
import android.widget.ListView;
import android.widget.SpinnerAdapter;


/**
 * A view that displays one child at a time and lets the user pick among them.
 * The items in the Spinner come from the {@link Adapter} associated with
 * this view.
 *
 * <p>See the <a href="{@docRoot}resources/tutorials/views/hello-spinner.html">Spinner
 * tutorial</a>.</p>
 * 
 * @attr ref android.R.styleable#Spinner_prompt
 */
public class IcsSpinner extends IcsAbsSpinner implements OnClickListener {
    // Only measure this many items to get a decent max width.
    private static final int MAX_ITEMS_MEASURED = 15;
    
    /**
     * Use a dropdown anchored to the Spinner for selecting spinner options.
     */
    public static final int MODE_DROPDOWN = 1;
    
    private SpinnerPopup mPopup;
    private DropDownAdapter mTempAdapter;
    int mDropDownWidth;

    private int mGravity;
    private boolean mDisableChildrenWhenDisabled;

    private Rect mTempRect = new Rect();

    /**
     * Construct a new spinner with the given context's theme, the supplied attribute set,
     * and default style.
     *
     * @param context The Context the view is running in, through which it can
     *        access the current theme, resources, etc.
     * @param attrs The attributes of the XML tag that is inflating the view.
     * @param defStyle The default style to apply to this view. If 0, no style
     *        will be applied (beyond what is included in the theme). This may
     *        either be an attribute resource, whose value will be retrieved
     *        from the current theme, or an explicit style resource.
     */
    public IcsSpinner(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);

        TypedArray a = context.obtainStyledAttributes(attrs,
                com.android.internal.R.styleable.Spinner, defStyle, 0);

        
        DropdownPopup popup = new DropdownPopup(context, attrs, defStyle);

        mDropDownWidth = a.getLayoutDimension(
                com.android.internal.R.styleable.Spinner_dropDownWidth,
                ViewGroup.LayoutParams.WRAP_CONTENT);
        popup.setBackgroundDrawable(a.getDrawable(
                com.android.internal.R.styleable.Spinner_popupBackground));
        final int verticalOffset = a.getDimensionPixelOffset(
                com.android.internal.R.styleable.Spinner_dropDownVerticalOffset, 0);
        if (verticalOffset != 0) {
            popup.setVerticalOffset(verticalOffset);
        }

        final int horizontalOffset = a.getDimensionPixelOffset(
                com.android.internal.R.styleable.Spinner_dropDownHorizontalOffset, 0);
        if (horizontalOffset != 0) {
            popup.setHorizontalOffset(horizontalOffset);
        }

        mPopup = popup;
        
        mGravity = a.getInt(com.android.internal.R.styleable.Spinner_gravity, Gravity.CENTER);

        mPopup.setPromptText(a.getString(com.android.internal.R.styleable.Spinner_prompt));

        mDisableChildrenWhenDisabled = a.getBoolean(
                com.android.internal.R.styleable.Spinner_disableChildrenWhenDisabled, false);

        a.recycle();

        // Base constructor can call setAdapter before we initialize mPopup.
        // Finish setting things up if this happened.
        if (mTempAdapter != null) {
            mPopup.setAdapter(mTempAdapter);
            mTempAdapter = null;
        }
    }

    @Override
    public void setEnabled(boolean enabled) {
        super.setEnabled(enabled);
        if (mDisableChildrenWhenDisabled) {
            final int count = getChildCount();
            for (int i = 0; i < count; i++) {
                getChildAt(i).setEnabled(enabled);
            }
        }
    }

    /**
     * Describes how the selected item view is positioned. Currently only the horizontal component
     * is used. The default is determined by the current theme.
     *
     * @param gravity See {@link android.view.Gravity}
     *
     * @attr ref android.R.styleable#Spinner_gravity
     */
    public void setGravity(int gravity) {
        if (mGravity != gravity) {
            if ((gravity & Gravity.HORIZONTAL_GRAVITY_MASK) == 0) {
                gravity |= Gravity.LEFT;
            }
            mGravity = gravity;
            requestLayout();
        }
    }

    @Override
    public void setAdapter(SpinnerAdapter adapter) {
        super.setAdapter(adapter);

        if (mPopup != null) {
            mPopup.setAdapter(new DropDownAdapter(adapter));
        } else {
            mTempAdapter = new DropDownAdapter(adapter);
        }
    }

    @Override
    public int getBaseline() {
        View child = null;
        SpinnerAdapter adapter = getAdapter();

        if (getChildCount() > 0) {
            child = getChildAt(0);
        } else if (adapter != null && adapter.getCount() > 0) {
            child = makeAndAddView(0);
            //XXX mRecycler.put(0, child);
            removeAllViewsInLayout();
        }

        if (child != null) {
            final int childBaseline = child.getBaseline();
            return childBaseline >= 0 ? child.getTop() + childBaseline : -1;
        } else {
            return -1;
        }
    }

    @Override
    protected void onDetachedFromWindow() {
        super.onDetachedFromWindow();
        
        if (mPopup != null && mPopup.isShowing()) {
            mPopup.dismiss();
        }
    }

    /**
     * <p>A spinner does not support item click events. Calling this method
     * will raise an exception.</p>
     *
     * @param l this listener will be ignored
     */
    @Override
    public void setOnItemClickListener(OnItemClickListener l) {
        throw new RuntimeException("setOnItemClickListener cannot be used with a spinner.");
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        if (mPopup != null && MeasureSpec.getMode(widthMeasureSpec) == MeasureSpec.AT_MOST) {
            final int measuredWidth = getMeasuredWidth();
            setMeasuredDimension(Math.min(Math.max(measuredWidth,
                    measureContentWidth(getAdapter(), getBackground())),
                    MeasureSpec.getSize(widthMeasureSpec)),
                    getMeasuredHeight());
        }
    }

    /**
     * @see android.view.View#onLayout(boolean,int,int,int,int)
     *
     * Creates and positions all views
     *
     */
    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        super.onLayout(changed, l, t, r, b);
        mInLayout = true;
        layout(0, false);
        mInLayout = false;
    }
    boolean mInLayout;

    /**
     * Creates and positions all views for this Spinner.
     *
     * @param delta Change in the selected position. +1 moves selection is moving to the right,
     * so views are scrolling to the left. -1 means selection is moving to the left.
     */
    //XXX @Override
    void layout(int delta, boolean animate) {
        int childrenLeft = mSpinnerPadding.left;
        int childrenWidth = getRight() - getLeft() - mSpinnerPadding.left - mSpinnerPadding.right;

        if (mDataChanged) {
            handleDataChanged();
        }

        // Handle the empty set by removing all views
        if (getAdapter().getCount() == 0) {
            resetList();
            return;
        }

        if (mNextSelectedPosition >= 0) {
            setSelectedPositionInt(mNextSelectedPosition);
        }

        recycleAllViews();

        // Clear out old views
        removeAllViewsInLayout();

        // Make selected view and position it
        mFirstPosition = getSelectedItemPosition();
        View sel = makeAndAddView(mSelectedPosition);
        int width = sel.getMeasuredWidth();
        int selectedOffset = childrenLeft;
        switch (mGravity & Gravity.HORIZONTAL_GRAVITY_MASK) {
            case Gravity.CENTER_HORIZONTAL:
                selectedOffset = childrenLeft + (childrenWidth / 2) - (width / 2);
                break;
            case Gravity.RIGHT:
                selectedOffset = childrenLeft + childrenWidth - width;
                break;
        }
        sel.offsetLeftAndRight(selectedOffset);

        // Flush any cached views that did not get reused above
        //XXX mRecycler.clear();

        invalidate();

        checkSelectionChanged();

        mDataChanged = false;
        mNeedSync = false;
        setNextSelectedPositionInt(mSelectedPosition);
    }

    /**
     * Obtain a view, either by pulling an existing view from the recycler or
     * by getting a new one from the adapter. If we are animating, make sure
     * there is enough information in the view's layout parameters to animate
     * from the old to new positions.
     *
     * @param position Position in the spinner for the view to obtain
     * @return A view that has been added to the spinner
     */
    private View makeAndAddView(int position) {

        View child;

        if (!mDataChanged) {
            child = mRecycler.get(position);
            if (child != null) {
                // Position the view
                setUpChild(child);

                return child;
            }
        }

        // Nothing found in the recycler -- ask the adapter for a view
        child = getAdapter().getView(position, null, this);

        // Position the view
        setUpChild(child);

        return child;
    }

    /**
     * Helper for makeAndAddView to set the position of a view
     * and fill out its layout paramters.
     *
     * @param child The view to position
     */
    private void setUpChild(View child) {

        // Respect layout params that are already in the view. Otherwise
        // make some up...
        ViewGroup.LayoutParams lp = child.getLayoutParams();
        if (lp == null) {
            lp = generateDefaultLayoutParams();
        }

        addViewInLayout(child, 0, lp);

        child.setSelected(hasFocus());
        if (mDisableChildrenWhenDisabled) {
            child.setEnabled(isEnabled());
        }

        // Get measure specs
        int childHeightSpec = ViewGroup.getChildMeasureSpec(mHeightMeasureSpec,
                mSpinnerPadding.top + mSpinnerPadding.bottom, lp.height);
        int childWidthSpec = ViewGroup.getChildMeasureSpec(mWidthMeasureSpec,
                mSpinnerPadding.left + mSpinnerPadding.right, lp.width);

        // Measure child
        child.measure(childWidthSpec, childHeightSpec);

        int childLeft;
        int childRight;

        // Position vertically based on gravity setting
        int childTop = mSpinnerPadding.top
                + ((getMeasuredHeight() - mSpinnerPadding.bottom -
                        mSpinnerPadding.top - child.getMeasuredHeight()) / 2);
        int childBottom = childTop + child.getMeasuredHeight();

        int width = child.getMeasuredWidth();
        childLeft = 0;
        childRight = childLeft + width;

        child.layout(childLeft, childTop, childRight, childBottom);
    }

    @Override
    public boolean performClick() {
        boolean handled = super.performClick();
        
        if (!handled) {
            handled = true;

            if (!mPopup.isShowing()) {
                mPopup.show();
            }
        }

        return handled;
    }
    
    public void onClick(DialogInterface dialog, int which) {
        setSelection(which);
        dialog.dismiss();
    }

    /**
     * Sets the prompt to display when the dialog is shown.
     * @param prompt the prompt to set
     */
    public void setPrompt(CharSequence prompt) {
        mPopup.setPromptText(prompt);
    }

    /**
     * Sets the prompt to display when the dialog is shown.
     * @param promptId the resource ID of the prompt to display when the dialog is shown
     */
    public void setPromptId(int promptId) {
        setPrompt(getContext().getText(promptId));
    }

    /**
     * @return The prompt to display when the dialog is shown
     */
    public CharSequence getPrompt() {
        return mPopup.getHintText();
    }

    int measureContentWidth(SpinnerAdapter adapter, Drawable background) {
        if (adapter == null) {
            return 0;
        }

        int width = 0;
        View itemView = null;
        int itemType = 0;
        final int widthMeasureSpec =
            MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);
        final int heightMeasureSpec =
            MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);

        // Make sure the number of items we'll measure is capped. If it's a huge data set
        // with wildly varying sizes, oh well.
        int start = Math.max(0, getSelectedItemPosition());
        final int end = Math.min(adapter.getCount(), start + MAX_ITEMS_MEASURED);
        final int count = end - start;
        start = Math.max(0, start - (MAX_ITEMS_MEASURED - count));
        for (int i = start; i < end; i++) {
            final int positionType = adapter.getItemViewType(i);
            if (positionType != itemType) {
                itemType = positionType;
                itemView = null;
            }
            itemView = adapter.getView(i, itemView, this);
            if (itemView.getLayoutParams() == null) {
                itemView.setLayoutParams(new ViewGroup.LayoutParams(
                        ViewGroup.LayoutParams.WRAP_CONTENT,
                        ViewGroup.LayoutParams.WRAP_CONTENT));
            }
            itemView.measure(widthMeasureSpec, heightMeasureSpec);
            width = Math.max(width, itemView.getMeasuredWidth());
        }

        // Add background padding to measured width
        if (background != null) {
            background.getPadding(mTempRect);
            width += mTempRect.left + mTempRect.right;
        }

        return width;
    }

    /**
     * <p>Wrapper class for an Adapter. Transforms the embedded Adapter instance
     * into a ListAdapter.</p>
     */
    private static class DropDownAdapter implements ListAdapter, SpinnerAdapter {
        private SpinnerAdapter mAdapter;
        private ListAdapter mListAdapter;

        /**
         * <p>Creates a new ListAdapter wrapper for the specified adapter.</p>
         *
         * @param adapter the Adapter to transform into a ListAdapter
         */
        public DropDownAdapter(SpinnerAdapter adapter) {
            this.mAdapter = adapter;
            if (adapter instanceof ListAdapter) {
                this.mListAdapter = (ListAdapter) adapter;
            }
        }

        public int getCount() {
            return mAdapter == null ? 0 : mAdapter.getCount();
        }

        public Object getItem(int position) {
            return mAdapter == null ? null : mAdapter.getItem(position);
        }

        public long getItemId(int position) {
            return mAdapter == null ? -1 : mAdapter.getItemId(position);
        }

        public View getView(int position, View convertView, ViewGroup parent) {
            return getDropDownView(position, convertView, parent);
        }

        public View getDropDownView(int position, View convertView, ViewGroup parent) {
            return mAdapter == null ? null :
                    mAdapter.getDropDownView(position, convertView, parent);
        }

        public boolean hasStableIds() {
            return mAdapter != null && mAdapter.hasStableIds();
        }

        public void registerDataSetObserver(DataSetObserver observer) {
            if (mAdapter != null) {
                mAdapter.registerDataSetObserver(observer);
            }
        }

        public void unregisterDataSetObserver(DataSetObserver observer) {
            if (mAdapter != null) {
                mAdapter.unregisterDataSetObserver(observer);
            }
        }

        /**
         * If the wrapped SpinnerAdapter is also a ListAdapter, delegate this call.
         * Otherwise, return true. 
         */
        public boolean areAllItemsEnabled() {
            final ListAdapter adapter = mListAdapter;
            if (adapter != null) {
                return adapter.areAllItemsEnabled();
            } else {
                return true;
            }
        }

        /**
         * If the wrapped SpinnerAdapter is also a ListAdapter, delegate this call.
         * Otherwise, return true.
         */
        public boolean isEnabled(int position) {
            final ListAdapter adapter = mListAdapter;
            if (adapter != null) {
                return adapter.isEnabled(position);
            } else {
                return true;
            }
        }

        public int getItemViewType(int position) {
            return 0;
        }

        public int getViewTypeCount() {
            return 1;
        }
        
        public boolean isEmpty() {
            return getCount() == 0;
        }
    }
    
    /**
     * Implements some sort of popup selection interface for selecting a spinner option.
     * Allows for different spinner modes.
     */
    private interface SpinnerPopup {
        public void setAdapter(ListAdapter adapter);
        
        /**
         * Show the popup
         */
        public void show();
        
        /**
         * Dismiss the popup
         */
        public void dismiss();
        
        /**
         * @return true if the popup is showing, false otherwise.
         */
        public boolean isShowing();
        
        /**
         * Set hint text to be displayed to the user. This should provide
         * a description of the choice being made.
         * @param hintText Hint text to set.
         */
        public void setPromptText(CharSequence hintText);
        public CharSequence getHintText();
    }
    
    
    private class DropdownPopup extends IcsListPopupWindow implements SpinnerPopup {
        private CharSequence mHintText;
        private ListAdapter mAdapter;

        public DropdownPopup(Context context, AttributeSet attrs, int defStyleRes) {
            super(context, attrs, 0, defStyleRes);

            setAnchorView(IcsSpinner.this);
            setModal(true);
            setPromptPosition(POSITION_PROMPT_ABOVE);
            setOnItemClickListener(new OnItemClickListener() {
                public void onItemClick(AdapterView parent, View v, int position, long id) {
                    IcsSpinner.this.setSelection(position);
                    dismiss();
                }
            });
        }
        
        @Override
        public void setAdapter(ListAdapter adapter) {
            super.setAdapter(adapter);
            mAdapter = adapter;
        }

        public CharSequence getHintText() {
            return mHintText;
        }
        
        public void setPromptText(CharSequence hintText) {
            // Hint text is ignored for dropdowns, but maintain it here.
            mHintText = hintText;
        }

        @Override
        public void show() {
            final int spinnerPaddingLeft = IcsSpinner.this.getPaddingLeft();
            if (mDropDownWidth == WRAP_CONTENT) {
                final int spinnerWidth = IcsSpinner.this.getWidth();
                final int spinnerPaddingRight = IcsSpinner.this.getPaddingRight();
                setContentWidth(Math.max(
                        measureContentWidth((SpinnerAdapter) mAdapter, getBackground()),
                        spinnerWidth - spinnerPaddingLeft - spinnerPaddingRight));
            } else if (mDropDownWidth == MATCH_PARENT) {
                final int spinnerWidth = IcsSpinner.this.getWidth();
                final int spinnerPaddingRight = IcsSpinner.this.getPaddingRight();
                setContentWidth(spinnerWidth - spinnerPaddingLeft - spinnerPaddingRight);
            } else {
                setContentWidth(mDropDownWidth);
            }
            final Drawable background = getBackground();
            int bgOffset = 0;
            if (background != null) {
                background.getPadding(mTempRect);
                bgOffset = -mTempRect.left;
            }
            setHorizontalOffset(bgOffset + spinnerPaddingLeft);
            setInputMethodMode(ListPopupWindow.INPUT_METHOD_NOT_NEEDED);
            super.show();
            getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE);
            setSelection(IcsSpinner.this.getSelectedItemPosition());
        }
    }
}