android垂直Gallery

package android.wheel.test; import java.util.LinkedList; import java.util.List; import android.content.Context; import android.database.DataSetObserver; import android.graphics.Canvas; import android.graphics.drawable.Drawable; import android.graphics.drawable.GradientDrawable; import android.graphics.drawable.GradientDrawable.Orientation; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.View; import android.view.ViewGroup.LayoutParams; import android.view.animation.Interpolator; import android.wheel.R; import android.wheel.test.adapter.WheelViewAdapter; import android.widget.LinearLayout; /** * Numeric wheel view. * * @author Yuri Kanivets */ public class WheelView extends View { /** Top and bottom shadows colors */ private static final int[] SHADOWS_COLORS = new int[] { 0xFF111111, 0x00AAAAAA, 0x00AAAAAA }; /** Top and bottom items offset (to hide that) */ private static final int ITEM_OFFSET_PERCENT = 10; /** Left and right padding value */ private static final int PADDING = 10; /** Default count of visible items */ private static final int DEF_VISIBLE_ITEMS = 5; // Wheel Values private int currentItem = 0; // Count of visible items private int visibleItems = DEF_VISIBLE_ITEMS; // Item height private int itemHeight = 0; // Center Line private Drawable centerDrawable; // Shadows drawables private GradientDrawable topShadow; private GradientDrawable bottomShadow; // Scrolling private WheelScroller scroller; private boolean isScrollingPerformed; private int scrollingOffset; // Cyclic boolean isCyclic = false; // Items layout private LinearLayout itemsLayout; // The number of first item in layout private int firstItem; // View adapter private WheelViewAdapter viewAdapter; // Recycle private WheelRecycle recycle = new WheelRecycle(this); // Listeners private List<OnWheelChangedListener> changingListeners = new LinkedList<OnWheelChangedListener>(); private List<OnWheelScrollListener> scrollingListeners = new LinkedList<OnWheelScrollListener>(); private List<OnWheelClickedListener> clickingListeners = new LinkedList<OnWheelClickedListener>(); /** * Constructor */ public WheelView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); initData(context); } /** * Constructor */ public WheelView(Context context, AttributeSet attrs) { super(context, attrs); initData(context); } /** * Constructor */ public WheelView(Context context) { super(context); initData(context); } /** * Initializes class data * @param context the context */ private void initData(Context context) { scroller = new WheelScroller(getContext(), scrollingListener); } // Scrolling listener WheelScroller.ScrollingListener scrollingListener = new WheelScroller.ScrollingListener() { public void onStarted() { isScrollingPerformed = true; notifyScrollingListenersAboutStart(); } public void onScroll(int distance) { doScroll(distance); int height = getHeight(); if (scrollingOffset > height) { scrollingOffset = height; scroller.stopScrolling(); } else if (scrollingOffset < -height) { scrollingOffset = -height; scroller.stopScrolling(); } } public void onFinished() { if (isScrollingPerformed) { notifyScrollingListenersAboutEnd(); isScrollingPerformed = false; } scrollingOffset = 0; invalidate(); } public void onJustify() { if (Math.abs(scrollingOffset) > WheelScroller.MIN_DELTA_FOR_SCROLLING) { scroller.scroll(scrollingOffset, 0); } } }; /** * Set the the specified scrolling interpolator * @param interpolator the interpolator */ public void setInterpolator(Interpolator interpolator) { scroller.setInterpolator(interpolator); } /** * Gets count of visible items * * @return the count of visible items */ public int getVisibleItems() { return visibleItems; } /** * Sets the desired count of visible items. * Actual amount of visible items depends on wheel layout parameters. * To apply changes and rebuild view call measure(). * * @param count the desired count for visible items */ public void setVisibleItems(int count) { visibleItems = count; } /** * Gets view adapter * @return the view adapter */ public WheelViewAdapter getViewAdapter() { return viewAdapter; } // Adapter listener private DataSetObserver dataObserver = new DataSetObserver() { @Override public void onChanged() { invalidateWheel(false); } @Override public void onInvalidated() { invalidateWheel(true); } }; /** * Sets view adapter. Usually new adapters contain different views, so * it needs to rebuild view by calling measure(). * * @param viewAdapter the view adapter */ public void setViewAdapter(WheelViewAdapter viewAdapter) { if (this.viewAdapter != null) { this.viewAdapter.unregisterDataSetObserver(dataObserver); } this.viewAdapter = viewAdapter; if (this.viewAdapter != null) { this.viewAdapter.registerDataSetObserver(dataObserver); } invalidateWheel(true); } /** * Adds wheel changing listener * @param listener the listener */ public void addChangingListener(OnWheelChangedListener listener) { changingListeners.add(listener); } /** * Removes wheel changing listener * @param listener the listener */ public void removeChangingListener(OnWheelChangedListener listener) { changingListeners.remove(listener); } /** * Notifies changing listeners * @param oldValue the old wheel value * @param newValue the new wheel value */ protected void notifyChangingListeners(int oldValue, int newValue) { for (OnWheelChangedListener listener : changingListeners) { listener.onChanged(this, oldValue, newValue); } } /** * Adds wheel scrolling listener * @param listener the listener */ public void addScrollingListener(OnWheelScrollListener listener) { scrollingListeners.add(listener); } /** * Removes wheel scrolling listener * @param listener the listener