在坛子里看到的,自己弄个Android-仿iPhone滚轮控件效果:
这个滚动的WheelView
- /*
- * Android Wheel Control.
- * https://code.google.com/p/android-wheel/
- *
- * Copyright 2010 Yuri Kanivets
- *
- * 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 kankan.wheel.widget;
-
- import java.util.LinkedList;
- import java.util.List;
-
- import android.content.Context;
- import android.graphics.Canvas;
- import android.graphics.Paint;
- import android.graphics.Rect;
- import android.graphics.drawable.Drawable;
- import android.graphics.drawable.GradientDrawable;
- import android.graphics.drawable.GradientDrawable.Orientation;
- import android.os.Handler;
- import android.os.Message;
- import android.text.Layout;
- import android.text.StaticLayout;
- import android.text.TextPaint;
- import android.util.AttributeSet;
- import android.util.FloatMath;
- import android.view.GestureDetector;
- import android.view.GestureDetector.SimpleOnGestureListener;
- import android.view.MotionEvent;
- import android.view.View;
- import android.view.animation.Interpolator;
- import android.widget.Scroller;
-
- import com.shao.pwd.R;
-
- /**
- * Numeric wheel view.
- *
- * @author Yuri Kanivets
- */
- public class WheelView extends View {
- /** Scrolling duration */
- private static final int SCROLLING_DURATION = 400;
-
- /** Minimum delta for scrolling */
- private static final int MIN_DELTA_FOR_SCROLLING = 1;
-
- /** Current value & label text color */
- private static final int VALUE_TEXT_COLOR = 0xF0000000;
-
- /** Items text color */
- private static final int ITEMS_TEXT_COLOR = 0xFF000000;
-
- /** Top and bottom shadows colors */
- private static final int[] SHADOWS_COLORS = new int[] { 0xFF111111,
- 0x00AAAAAA, 0x00AAAAAA };
-
- /** Additional items height (is added to standard text item height) */
- private static final int ADDITIONAL_ITEM_HEIGHT = 15;
-
- /** Text size */
- private static final int TEXT_SIZE = 24;
-
- /** Top and bottom items offset (to hide that) */
- private static final int ITEM_OFFSET = TEXT_SIZE / 5;
-
- /** Additional width for items layout */
- private static final int ADDITIONAL_ITEMS_SPACE = 10;
-
- /** Label offset */
- private static final int LABEL_OFFSET = 8;
-
- /** 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 WheelAdapter adapter = null;
- private int currentItem = 0;
-
- // Widths
- private int itemsWidth = 0;
- private int labelWidth = 0;
-
- // Count of visible items
- private int visibleItems = DEF_VISIBLE_ITEMS;
-
- // Item height
- private int itemHeight = 0;
-
- // Text paints
- private TextPaint itemsPaint;
- private TextPaint valuePaint;
-
- // Layouts
- private StaticLayout itemsLayout;
- private StaticLayout labelLayout;
- private StaticLayout valueLayout;
-
- // Label & background
- private String label;
- private Drawable centerDrawable;
-
- // Shadows drawables
- private GradientDrawable topShadow;
- private GradientDrawable bottomShadow;
-
- // Scrolling
- private boolean isScrollingPerformed;
- private int scrollingOffset;
-
- // Scrolling animation
- private GestureDetector gestureDetector;
- private Scroller scroller;
- private int lastScrollY;
-
- // Cyclic
- boolean isCyclic = false;
-
- // Listeners
- private List<OnWheelChangedListener> changingListeners = new LinkedList<OnWheelChangedListener>();
- private List<OnWheelScrollListener> scrollingListeners = new LinkedList<OnWheelScrollListener>();
-
- /**
- * 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) {
- gestureDetector = new GestureDetector(context, gestureListener);
- gestureDetector.setIsLongpressEnabled(false);
-
- scroller = new Scroller(context);
- }
-
- /**
- * Gets wheel adapter
- * @return the adapter
- */
- public WheelAdapter getAdapter() {
- return adapter;
- }
-
- /**
- * Sets wheel adapter
- * @param adapter the new wheel adapter
- */
- public void setAdapter(WheelAdapter adapter) {
- this.adapter = adapter;
- invalidateLayouts();
- invalidate();
- }
-
- /**
- * Set the the specified scrolling interpolator
- * @param interpolator the interpolator
- */
- public void setInterpolator(Interpolator interpolator) {
- scroller.forceFinished(true);
- scroller = new Scroller(getContext(), interpolator);
- }
-
- /**
- * Gets count of visible items
- *
- * @return the count of visible items
- */
- public int getVisibleItems() {
- return visibleItems;
- }
-
- /**
- * Sets count of visible items
- *
- * @param count
- * the new count
- */
- public void setVisibleItems(int count) {
- visibleItems = count;
- invalidate();
- }
-
- /**
- * Gets label
- *
- * @return the label
- */
- public String getLabel() {
- return label;
- }
-
- /**
- * Sets label
- *
- * @param newLabel
- * the label to set
- */
- public void setLabel(String newLabel) {
- if (label == null || !label.equals(newLabel)) {
- label = newLabel;
- labelLayout = null;
- invalidate();
- }
- }
-
- /**
- * 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
- */
- public void removeScrollingListener(OnWheelScrollListener listener) {
- scrollingListeners.remove(listener);
- }
-
- /**
- * Notifies listeners about starting scrolling
- */
- protected void notifyScrollingListenersAboutStart() {
- for (OnWheelScrollListener listener : scrollingListeners) {
- listener.onScrollingStarted(this);
- }
- }
-
- /**
- * Notifies listeners about ending scrolling
- */
- protected void notifyScrollingListenersAboutEnd() {
- for (OnWheelScrollListener listener : scrollingListeners) {
- listener.onScrollingFinished(this);
- }
- }
-
- /**
- * Gets current value
- *
- * @return the current value
- */
- public int getCurrentItem() {
- return currentItem;
- }
-
- /**
- * Sets the current item. Does nothing when index is wrong.
- *
- * @param index the item index
- * @param animated the animation flag
- */
- public void setCurrentItem(int index, boolean animated) {
- if (adapter == null || adapter.getItemsCount() == 0) {
- return; // throw?
- }
- if (index < 0 || index >= adapter.getItemsCount()) {
- if (isCyclic) {
- while (index < 0) {
- index += adapter.getItemsCount();
- }
- index %= adapter.getItemsCount();
- } else{
- return; // throw?
- }
- }
- if (index != currentItem) {
- if (animated) {
- scroll(index - currentItem, SCROLLING_DURATION);
- } else {
- invalidateLayouts();
-
- int old = currentItem;
- currentItem = index;
-
- notifyChangingListeners(old, currentItem);
-
- invalidate();
- }
- }
- }
-
- /**
- * Sets the current item w/o animation. Does nothing when index is wrong.
- *
- * @param index the item index
- */
- public void setCurrentItem(int index) {
- setCurrentItem(index, false);
- }
-
- /**
- * Tests if wheel is cyclic. That means before the 1st item there is shown the last one
- * @return true if wheel is cyclic
- */
- public boolean isCyclic() {
- return isCyclic;
- }
-
- /**
- * Set wheel cyclic flag
- * @param isCyclic the flag to set
- */
- public void setCyclic(boolean isCyclic) {
- this.isCyclic = isCyclic;
-
- invalidate();
- invalidateLayouts();
- }
-
- /**
- * Invalidates layouts
- */
- private void invalidateLayouts() {
- itemsLayout = null;
- valueLayout = null;
- scrollingOffset = 0;
- }
-
- /**
- * Initializes resources
- */
- private void initResourcesIfNecessary() {
- if (itemsPaint == null) {
- itemsPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG
- | Paint.FAKE_BOLD_TEXT_FLAG);
- //itemsPaint.density = getResources().getDisplayMetrics().density;
- itemsPaint.setTextSize(TEXT_SIZE);
- }
-
- if (valuePaint == null) {
- valuePaint = new TextPaint(Paint.ANTI_ALIAS_FLAG
- | Paint.FAKE_BOLD_TEXT_FLAG | Paint.DITHER_FLAG);
- //valuePaint.density = getResources().getDisplayMetrics().density;
- valuePaint.setTextSize(TEXT_SIZE);
- valuePaint.setShadowLayer(0.1f, 0, 0.1f, 0xFFC0C0C0);
- }
-
- if (centerDrawable == null) {
- centerDrawable = getContext().getResources().getDrawable(R.drawable.wheel_val);
- }
-
- if (topShadow == null) {
- topShadow = new GradientDrawable(Orientation.TOP_BOTTOM, SHADOWS_COLORS);
- }
-
- if (bottomShadow == null) {
- bottomShadow = new GradientDrawable(Orientation.BOTTOM_TOP, SHADOWS_COLORS);
- }
-
- setBackgroundResource(R.drawable.wheel_bg);
- }
-
- /**
- * Calculates desired height for layout
- *
- * @param layout
- * the source layout
- * @return the desired layout height
- */
- private int getDesiredHeight(Layout layout) {
- if (layout == null) {
- return 0;
- }
-
- int desired = getItemHeight() * visibleItems - ITEM_OFFSET * 2
- - ADDITIONAL_ITEM_HEIGHT;
-
- // Check against our minimum height
- desired = Math.max(desired, getSuggestedMinimumHeight());
-
- return desired;
- }
-
- /**
- * Returns text item by index
- * @param index the item index
- * @return the item or null
- */
- private String getTextItem(int index) {
- if (adapter == null || adapter.getItemsCount() == 0) {
- return null;
- }
- int count = adapter.getItemsCount();
- if ((index < 0 || index >= count) && !isCyclic) {
- return null;
- } else {
- while (index < 0) {
- index = count + index;
- }
- }
-
- index %= count;
- return adapter.getItem(index);
- }
-
- /**
- * Builds text depending on current value
- *
- * @param useCurrentValue
- * @return the text
- */
- private String buildText(boolean useCurrentValue) {
- StringBuilder itemsText = new StringBuilder();
- int addItems = visibleItems / 2 + 1;
-
- for (int i = currentItem - addItems; i <= currentItem + addItems; i++) {
- if (useCurrentValue || i != currentItem) {
- String text = getTextItem(i);
- if (text != null) {
- itemsText.append(text);
- }
- }
- if (i < currentItem + addItems) {
- itemsText.append("
");
- }
- }
-
- return itemsText.toString();
- }
-
- /**
- * Returns the max item length that can be present
- * @return the max length
- */
- private int getMaxTextLength() {
- WheelAdapter adapter = getAdapter();
- if (adapter == null) {
- return 0;
- }
-
- int adapterLength = adapter.getMaximumLength();
- if (adapterLength > 0) {
- return adapterLength;
- }
-
- String maxText = null;
- int addItems = visibleItems / 2;
- for (int i = Math.max(currentItem - addItems, 0);
- i < Math.min(currentItem + visibleItems, adapter.getItemsCount()); i++) {
- String text = adapter.getItem(i);
- if (text != null && (maxText == null || maxText.length() < text.length())) {
- maxText = text;
- }
- }
-
- return maxText != null ? maxText.length() : 0;
- }
-
- /**
- * Returns height of wheel item
- * @return the item height
- */
- private int getItemHeight() {
- if (itemHeight != 0) {
- return itemHeight;
- } else if (itemsLayout != null && itemsLayout.getLineCount() > 2) {
- itemHeight = itemsLayout.getLineTop(