/*
* Copyright (C) 2012 www.amsoft.cn
*
* 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.ab.view.wheel;
import java.util.LinkedList;
import java.util.List;
import android.app.Activity;
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.graphics.drawable.LayerDrawable;
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.DisplayMetrics;
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.ab.util.AbGraphicUtil;
import com.ab.util.AbViewUtil;
// TODO: Auto-generated Javadoc
/**
* © 2012 amsoft.cn
* 名称：AbWheelView.java
* 描述：轮子View
*
* @author 还如一梦中
* @version v1.0
* @date：2013-05-17 下午6:46:29
*/
public class AbWheelView extends View {
/** The m context. */
private Context mContext = null;
/** Scrolling duration. */
private static final int SCROLLING_DURATION = 400;
/** Minimum delta for scrolling. */
private static final int MIN_DELTA_FOR_SCROLLING = 1;
/** Items text color. */
private static final int ITEMS_TEXT_COLOR = 0xFF000000;
/** Top and bottom shadows colors. */
private static int[] SHADOWS_COLORS = new int[] { 0xFF111111, 0x00AAAAAA, 0x00AAAAAA };
/** Label offset. */
private static final int LABEL_OFFSET = 8;
/** Left and right padding value. */
private static final int PADDING = 5;
/** Default count of visible items. */
private static final int DEF_VISIBLE_ITEMS = 5;
// Wheel Values
/** The adapter. */
private AbWheelAdapter adapter = null;
/** The current item. */
private int currentItem = 0;
// Widths
/** The items width. */
private int itemsWidth = 0;
/** The label width. */
private int labelWidth = 0;
// Count of visible items
/** The visible items. */
private int visibleItems = DEF_VISIBLE_ITEMS;
// Item height
/** The item height. */
private int itemHeight = 0;
// Text paints
/** The items paint. */
private TextPaint itemsPaint;
/** The value paint. */
private TextPaint valuePaint;
/** The label paint. */
private TextPaint labelPaint;
// Layouts
/** The items layout. */
private StaticLayout itemsLayout;
/** The label layout. */
private StaticLayout labelLayout;
/** The value layout. */
private StaticLayout valueLayout;
// Label & background
/** The label. */
private String label;
// Scrolling
/** The is scrolling performed. */
private boolean isScrollingPerformed;
/** The scrolling offset. */
private int scrollingOffset;
// Scrolling animation
/** The gesture detector. */
private GestureDetector gestureDetector;
/** The scroller. */
private Scroller scroller;
/** The last scroll y. */
private int lastScrollY;
// Cyclic
/** The is cyclic. */
boolean isCyclic = false;
// Listeners
/** The changing listeners. */
private List<AbOnWheelChangedListener> changingListeners = new LinkedList<AbOnWheelChangedListener>();
/** The scrolling listeners. */
private List<AbOnWheelScrollListener> scrollingListeners = new LinkedList<AbOnWheelScrollListener>();
/** 中间覆盖条的背景图. */
private Drawable centerSelectDrawable;
/** 中间覆盖条的颜色，如果没有设置centerDrawable时才生效. */
private int[] centerSelectGradientColors = new int[] {0x70222222,0x70222222, 0x70EEEEEE};
/** The center select stroke width. */
private int centerSelectStrokeWidth = 1;
/** The center select stroke color. */
private int centerSelectStrokeColor = 0x70333333;
/** Shadows drawables. */
private GradientDrawable topShadow;
/** The bottom shadow. */
private GradientDrawable bottomShadow;
/** Current value. */
private int valueTextColor = 0xF0000000;
/** Current label text color. */
private int labelTextColor = 0xF0000000;
/** 轮子的背景 底部的颜色 */
private int[] bottomGradientColors = new int[] { 0x333, 0xDDD, 0x333 };
/** 轮子的背景 顶部的颜色 */
private int[] topGradientColors = new int[] { 0xAAA, 0xFFF, 0xAAA };
/** The top stroke width. */
private int topStrokeWidth = 1;
/** The top stroke color. */
private int topStrokeColor = 0xFF333333;
/** 值的文字大小. */
private int valueTextSize = 35;
/** 标签的文字大小. */
private int labelTextSize = 35;
/** 单行文字的高度. */
private int itemOffset = valueTextSize / 5;
/** 中间覆盖条高度. */
private int additionalItemHeight = 30;
/**
* Constructor.
*
* @param context the context
* @param attrs the attrs
* @param defStyle the def style
*/
public AbWheelView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initData(context);
}
/**
* Constructor.
*
* @param context the context
* @param attrs the attrs
*/
public AbWheelView(Context context, AttributeSet attrs) {
super(context, attrs);
initData(context);
}
/**
* Constructor.
*
* @param context the context
*/
public AbWheelView(Context context) {
super(context);
initData(context);
}
/**
* Initializes class data.
*
* @param context the context
*/
private void initData(Context context) {
mContext = context;
gestureDetector = new GestureDetector(context, gestureListener);
gestureDetector.setIsLongpressEnabled(false);
scroller = new Scroller(context);
}
/**
* Gets wheel adapter.
*
* @return the adapter
*/
public AbWheelAdapter getAdapter() {
return adapter;
}
/**
* Sets wheel adapter.
*
* @param adapter the new wheel adapter
*/
public void setAdapter(AbWheelAdapter adapter) {
this.adapter = adapter;
invalidateLayouts();
// 重绘
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(AbOnWheelChangedListener listener) {
changingListeners.add(listener);
}
/**
* Removes wheel changing listener.
*
* @param listener the listener
*/
public void removeChangingListener(AbOnWheelChangedListener 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 (AbOnWheelChangedListener listener : changingListeners) {
listener.onChanged(this, oldValue, newValue);
}
}
/**
* Adds wheel scrolling listener.
*
* @param listener the listener
*/
public void addScrollingListener(AbOnWheelScrollListener listener) {
scrollingListeners.add(listener);
}
/**
* Removes wheel scrolling listener.
*
* @param listener the listener
*/
public void removeScrollingListener(AbOnWheelScrollListener listener) {
scrollingListeners.remove(listener);
}
/**
* Notifies listeners about starting scrolling.
*/
protected void notifyScrollingListenersAboutStart() {
for (AbOnWheelScrollListener listener : scrollingListeners) {
listener.onScrollingStarted(this);
}
}
/**
* Notifies listeners about ending scrolling.
*/
protected void notifyScrollingListenersAboutEnd() {
for (AbOnWheelScrollListener 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(valueTextSize);
}
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(valueTextSize);
}
if (labelPaint == null) {
labelPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG | Paint.FAKE_BOLD_TEXT_FLAG | Paint.DITHER_FLAG);
labelPaint.setTextSize(labelTextSize);
//设置阴影
labelPaint.setShadowLayer(0.5f, 0, 1, 0xFFFFFFFF);
}
//如果没设置中间的选中条用默认的颜色
if (centerSelectDrawable == null) {
GradientDrawable mGradientDrawable = new GradientDrawable(Orientation.BOTTOM_TOP, centerSelectGradientColors);
mGradientDrawable.setStroke(centerSelectStrokeWidth, centerSelectStrokeColor);
centerSelectDrawable = mGradientDrawable;
}
/* Android中提供了Shader类专门用来渲染图像以及一些几何图形，
Shader下面包括几个直接子类，分别是BitmapShader、 ComposeShader、LinearGradient、
RadialGradient、SweepGradient。 BitmapShader主要用来渲染图像，
LinearGradient 用来进行梯度渲染，RadialGradient 用来进行环形渲染，
SweepGradient
用来进行梯度渲染，ComposeShader则是一个 混合渲染，可以和其它几个子类组合起来使用。 */
//上边界渐变层
if (topShadow == null) {
topShadow = new GradientDrawable(Orientation.TOP_BOTTOM, SHADOWS_COLORS);
}
//下边界渐变层
if (bottomShadow == null) {
bottomShadow = new GradientDrawable(Orientation.BOTTOM_TOP, SHADOWS_COLORS);
}
if(this.getBackground()==null){
//原来用颜色渐变实现setBackgroundDrawable(layerDrawable);
//底部的颜色
GradientDrawable mGradientDrawable1 = new GradientDrawable(Orientation.TOP_BOTTOM, topGradientColors);
GradientDrawable mGradientDrawable2 = new GradientDrawable(Orientation.BOTTOM_TOP, bottomGradientColors);
mGradientDrawable1.setStroke(topStrokeWidth, topStrokeColor);
mGradientDrawable1.setShape(GradientDrawable.RECTANGLE);
mGradientDrawable2.setShape(GradientDrawable.RECTANGLE);
mGradientDrawable1.setGradientType(GradientDrawable.LINEAR_GRADIENT );
mGradientDrawable2.setGradientType(GradientDrawable.LINEAR_GRADIENT );
GradientDrawable[] mDrawables = new GradientDrawable[2];
mDrawables[0] = mGradientDrawable1;
mDrawables[1] = mGradientDrawable2;
LayerDrawable layerDrawable = new LayerDrawable(mDrawables);
layerDrawable.setLayerInset(0, 0, 0, 0, 0); //第一个参数0代表数组的第1个元素
layerDrawable.setLayerInset(1, 4, 1, 4, 1); //第一个参数1代表数组的第2个元素
setBackgroundDrawable(layerDrawable);
}
}
/**
* 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 - itemOffset * 2 - additionalItemHeight;
// 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 the use current value
* @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("\n");
}
}
return itemsText.toString();
}
/**
* Returns the max item length that can be present.
*
* @return the max length
*/
private int getMaxTextLength() {
AbWheelAdapter adapter = getAdapter();
if (adapter == null) {
return 0;
}
int adapterLength = adapter.getMaximumLength();
if (adapterLength > 0) {
return adapterLength;
}else{
return 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(2) - itemsLayout.getLineTop(1);
return itemHeight;
}
return getHeight() / visibleItems;
}
/**
* Calculates control width and creates text layouts.
*
* @param widthSize the input layout width
* @param mode the layout mode
* @return the calculated control width
*/
private int calculateLayoutWidth(int widthSize, int mode) {
initResourcesIfNecessary();
int width = widthSize;
int maxLength = getMaxTextLength();
if (maxLength > 0) {
//一个字符宽度
float textWidth = (int)AbGraphicUtil.getStringWidth("0", labelPaint);
//不算lable的宽度
itemsWidth = (int) (maxLength * textWidth);
} else {
itemsWidth = 0;
}
//空隙宽度
itemsWidth += LABEL_OFFSET;
//label宽度的计算
labelWidth = 0;
if (label != null && label.length() > 0) {
labelWidth = (int)AbGraphicUtil.getStringWidth(label, labelPaint);
}
boolean recalculate = false;
if (mode == MeasureSpec.EXACTLY) {
width = widthSize;
recalculate = true;
} else {
width = itemsWidth + labelWidth + 2 * PADDING;
//有Label，添加一个间距
if (labelWidth > 0) {
width += LABEL_OFFSET;
}
// Check against our minimum width
width = Math.max(width, getSuggestedMinimumWidth());
if (mode == MeasureSpec.AT_MOST && widthSize < width) {
width = widthSize;
recalculate = true;
}
}
if (recalculate) {
// recalculate width
int pureWidth = width - LABEL_OFFSET - 2 * PADDING;
if (pureWidth <= 0) {
itemsWidth = labelWidth = 0;
}
if (labelWidth > 0) {
//对半分后再调整下
int newItemsWidth = (pureWidth+itemsWidth)/2-LABEL_OFFSET;
int newLabelWidth = pureWidth - newItemsWidth;
if(newItemsWidth < itemsWidth){
//放不下了,看label有空余宽度没有
itemsWidth = pureWidth-labelWidth;
}else{
labelWidth = newLabelWidth;
itemsWidth = newItemsWidth;
}
} else {
// no label
itemsWidth = pureWidth + LABEL_OFFSET;
}
}
if (itemsWidth > 0) {
createLayouts(itemsWidth, labelWidth);
}
return width;
}
/**
* Creates layouts.
*
* @param widthItems width of items layout
* @param widthLabel width of label layout
*/
private void createLayouts(int widthItems, int widthLabel) {
//190 94
//if(D)Log.d(TAG, "widthItems:"+widthItems);
//if(D)Log.d(TAG, "widthLabel:"+widthLabel);
if (itemsLayout == null || itemsLayout.getWidth() > widthItems) {
itemsLayout = new StaticLayout(buildText(isScrollingPerformed), itemsPaint, widthItems,
widthLabel > 0 ? Layout.Alignment.ALIGN_OPPOSITE : Layout.Alignment.ALIGN_CENTER, 1,
additionalItemHeight, false);
} else {
itemsLayout.increaseWidthTo(widthItems);
}
if (!isScrollingPerformed && (valueLayout == null || valueLayout.getWidth() > widthItems)) {
String text = getAdapter() != null ? getAdapter().getItem(currentItem) : null;
valueLayout = new StaticLayout(text != null ? text : "", valuePaint, widthItems,
widthLabel > 0 ? Layout.Alignment.ALIGN_OPPOSITE : Layout.Alignment.ALIGN_CENTER, 1,
additionalItemHeight, false);
} else if (isScrollingPerformed) {
valueLayout = null;
} else {
valueLayout.increaseWidthTo(widthItems);
}
if (widthLabel > 0) {
if (labelLayout == null || labelLayout.getWidth() > widthLabel) {
labelLayout = new StaticLayout(label, labelPaint, widthLabel, Layout.Alignment.ALIGN_NORMAL, 1,
additionalItemHeight, false);
} else {
labelLayout.increaseWidthTo(widthLabel);
}
}
}
/**
* 描述：TODO.
*
* @version v1.0
* @param widthMeasureSpec the width measure spec
* @param heightMeasureSpec the height measure spec
* @see android.view.View#onMeasure(int, int)
* @author: amsoft.cn
* @date：2013-6-17 上午9:04:47
*/
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
int widthSize = MeasureSpec.getSize(widthMeasureSpec);
int heightSize = MeasureSpec.getSize(heightMeasureSpec);
int width = calculateLayoutWidth(widthSize, widthMode);
int height;
if (heightMode == MeasureSpec.EXACTLY) {
height = heightSize;
} else {
height = getDesiredHeight(itemsLayout);
if (heightMode == MeasureSpec.AT_MOST) {
height = Math.min(height, heightSize);
}
}
setMeasuredDimension(width, height);
}
/**
* 描述：TODO.
*
* @version v1.0
* @param canvas the canvas
* @see android.view.View#onDraw(android.graphics.Canvas)
* @author: amsoft.cn
* @date：2013-6-17 上午9:04:47
*/
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (itemsLayout == null) {
if (itemsWidth == 0) {
calculateLayoutWidth(getWidth(), MeasureSpec.EXACTLY);
} else {
createLayouts(itemsWidth, labelWidth);
}
}
if (itemsWidth > 0) {
canvas.save();
canvas.translate(PADDING, -itemOffset);
drawItems(canvas);
drawValue(canvas);
canvas.restore();
}
drawCenterRect(canvas);
drawShadows(canvas);
}
/**
* Draws shadows on top and bottom of control.
*
* @param canvas the canvas for drawing
*/
private void drawShadows(Canvas canvas) {
topShadow.setBounds(0, 0, getWidth(), getHeight() / visibleItems);
topShadow.draw(canvas);
bottomShadow.setBounds(0, getHeight() - getHeight() / visibleItems, getWidth(), getHeight());
bottomShadow.draw(canvas);
}
/**
* Draws value and label layout.
*
* @param canvas the canvas for drawing
*/
private void drawValue(Canvas canvas) {
valuePaint.setColor(valueTextColor);
valuePaint.drawableState = getDrawableState();
labelPaint.setColor(labelTextColor);
labelPaint.drawableState = getDrawableState();
Rect bounds = new Rect();
itemsLayout.getLineBounds(visibleItems / 2, bounds);
// draw label
if (labelLayout != null) {
canvas.save();
canvas.translate(itemsLayout.getWidth() + LABEL_OFFSET, bounds.top);
labelLayout.draw(canvas);
canvas.restore();
}
// draw current value
if (valueLayout != null) {
canvas.save();
canvas.translate(0, bounds.top + scrollingOffset);
valueLayout.draw(canvas);
canvas.restore();
}
}
/**
* Draws items.
*
* @param canvas the canvas for drawing
*/
private void drawItems(Canvas canvas) {
canvas.save();
int top = itemsLayout.getLineTop(1);
canvas.translate(0, -top + scrollingOffset);
itemsPaint.setColor(ITEMS_TEXT_COLOR);
itemsPaint.drawableState = getDrawableState();
itemsLayout.draw(canvas);
canvas.restore();
}
/**
* Draws rect for current value.
*
* @param canvas the canvas for drawing
*/
private void drawCenterRect(Canvas canvas) {
int center = getHeight() / 2;
int offset = getItemHeight() / 2;
centerSelectDrawable.setBounds(0, center - offset, getWidth(), center + offset);
centerSelectDrawable.draw(canvas);
}
/**
* 描述：TODO.
*
* @version v1.0
* @param event the event
* @return true, if successful
* @see android.view.View#onTouchEvent(android.view.MotionEvent)
* @author: amsoft.cn
* @date：2013-6-17 上午9:04:47
*/
@Override
public boolean onTouchEvent(MotionEvent event) {
AbWheelAdapter adapter = getAdapter();
if (adapter == null) {
return true;
}
if (!gestureDetector.onTouchEvent(event) && event.getAction() == MotionEvent.ACTION_UP) {
justify();
}
return true;
}
/**
* Scrolls the wheel.
*
* @param delta the scrolling value
*/
private void doScroll(int delta) {
scrollingOffset += delta;
int count = scrollingOffset / getItemHeight();
int pos = currentItem - count;
if (isCyclic && adapter.getItemsCount() > 0) {
// fix position by rotating
while (pos < 0) {
pos += adapter.getItemsCount();
}
pos %= adapter.getItemsCount();
} else if (isScrollingPerformed) {
//
if (pos < 0) {
count = currentItem;
pos = 0;
} else if (pos >= adapter.getItemsCount()) {
count = currentItem - adapter.getItemsCount() + 1;
pos = adapter.getItemsCount() - 1;
}
} else {
// fix position
pos = Math.max(pos, 0);
pos = Math.min(pos, adapter.getItemsCount() - 1);
}
int offset = scrollingOffset;
if (pos != currentItem) {
setCurrentItem(pos, false);
} else {
invalidate();
}
// update offset
scrollingOffset = offset - count * getItemHeight();
if (scrollingOffset > getHeight()) {
scrollingOffset = scrollingOffset % getHeight() + getHeight();
}
}
// gesture listener
/** The gesture listener. */
private SimpleOnGestureListener gestureListener = new SimpleOnGestureListener() {
public boolean onDown(MotionEvent e) {
if (isScrollingPerformed) {
scroller.forceFinished(true);
clearMessages();
return true;
}
return false;
}
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
startScrolling();
doScroll((int) -distanceY);
return true;
}
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
lastScrollY = currentItem * getItemHeight() + scrollingOffset;
int maxY = isCyclic ? 0x7FFFFFFF : adapter.getItemsCount() * getItemHeight();
int minY = isCyclic ? -maxY : 0;
scroller.fling(0, lastScrollY, 0, (int) -velocityY / 2, 0, 0, minY, maxY);
setNextMessage(MESSAGE_SCROLL);
return true;
}
};
// Messages
/** The message scroll. */
private final int MESSAGE_SCROLL = 0;
/** The message justify. */
private final int MESSAGE_JUSTIFY = 1;
/**
* Set next message to queue. Clears queue before.
* @param message the message to set
*/
private void setNextMessage(int message) {
clearMessages();
animationHandler.sendEmptyMessage(message);
}
/**
* Clears messages from queue.
*/
private void clearMessages() {
animationHandler.removeMessages(MESSAGE_SCROLL);
animationHandler.removeMessages(MESSAGE_JUSTIFY);
}
// animation handler
/** The animation handler. */
private Handler animationHandler = new Handler() {
public void handleMessage(Message msg) {
scroller.computeScrollOffset();
int currY = scroller.getCurrY();
int delta = lastScrollY - currY;
lastScrollY = currY;
if (delta != 0) {
doScroll(delta);
}
// scrolling is not finished when it comes to final Y
// so, finish it manually
if (Math.abs(currY - scroller.getFinalY()) < MIN_DELTA_FOR_SCROLLING) {
currY = scroller.getFinalY();
scroller.forceFinished(true);
}
if (!scroller.isFinished()) {
animationHandler.sendEmptyMessage(msg.what);
} else if (msg.what == MESSAGE_SCROLL) {
justify();
} else {
finishScrolling();
}
}
};
/**
* Justifies wheel.
*/
private void justify() {
if (adapter == null) {
return;
}
lastScrollY = 0;
int offset = scrollingOffset;
int itemHeight = getItemHeight();
boolean needToIncrease = offset > 0 ? currentItem < adapter.getItemsCount() : currentItem > 0;
if ((isCyclic || needToIncrease) && Math.abs((float) offset) > (float) itemHeight / 2) {
if (offset < 0)
offset += itemHeight + MIN_DELTA_FOR_SCROLLING;
else
offset -= itemHeight + MIN_DELTA_FOR_SCROLLING;
}
if (Math.abs(offset) > MIN_DELTA_FOR_SCROLLING) {
scroller.startScroll(0, 0, 0, offset, SCROLLING_DURATION);
setNextMessage(MESSAGE_JUSTIFY);
} else {
finishScrolling();
}
}
/**
* Starts scrolling.
*/
private void startScrolling() {
if (!isScrollingPerformed) {
isScrollingPerformed = true;
notifyScrollingListenersAboutStart();
}
}
/**
* Finishes scrolling.
*/
void finishScrolling() {
if (isScrollingPerformed) {
notifyScrollingListenersAboutEnd();
isScrollingPerformed = false;
}
invalidateLayouts();
invalidate();
}
/**
* Scroll the wheel.
*
* @param itemsToScroll the items to scroll
* @param time scrolling duration
*/
public void scroll(int itemsToScroll, int time) {
scroller.forceFinished(true);
lastScrollY = scrollingOffset;
int offset = itemsToScroll * getItemHeight();
scroller.startScroll(0, lastScrollY, 0, offset - lastScrollY, time);
setNextMessage(MESSAGE_SCROLL);
startScrolling();
}
/**
* Sets the value text size.
*
* @param textSize the new value text size
*/
public void setValueTextSize(int textSize) {
this.valueTextSize = AbViewUtil.scaleTextValue(mContext, textSize);
this.itemOffset = valueTextSize/5;
}
/**
* Gets the center select gradient colors.
*
* @return the center select gradient colors
*/
public int[] getCenterSelectGradientColors() {
return centerSelectGradientColors;
}
/**
* Sets the center select gradient colors.
*
* @param centerSelectGradientColors the new center select gradient colors
*/
public void setCenterSelectGradientColors(int[] centerSelectGradientColors) {
this.centerSelectGradientColors = centerSelectGradientColors;
}
/**
* Gets the center select stroke width.
*
* @return the center select stroke width
*/
public int getCenterSelectStrokeWidth() {
return centerSelectStrokeWidth;
}
/**
* Sets the center select stroke width.
*
* @param centerSelectStrokeWidth the new center select stroke width
*/
public void setCenterSelectStrokeWidth(int centerSelectStrokeWidth) {
this.centerSelectStrokeWidth = centerSelectStrokeWidth;
}
/**
* Gets the center select stroke color.
*
* @return the center select stroke color
*/
public int getCenterSelectStrokeColor() {
return centerSelectStrokeColor;
}
/**
* Sets the center select stroke color.
*
* @param centerSelectStrokeColor the new center select stroke color
*/
public void setCenterSelectStrokeColor(int centerSelectStrokeColor) {
this.centerSelectStrokeColor = centerSelectStrokeColor;
}
/**
* 描述：设置中间的选中层图片.
*
* @param centerSelectDrawable the new center select drawable
*/
public void setCenterSelectDrawable(Drawable centerSelectDrawable) {
this.centerSelectDrawable = centerSelectDrawable;
}
/**
* Sets the value text color.
*
* @param valueTextColor the new value text color
*/
public void setValueTextColor(int valueTextColor) {
this.valueTextColor = valueTextColor;
}
/**
* Sets the label text color.
*
* @param labelTextColor the new label text color
*/
public void setLabelTextColor(int labelTextColor) {
this.labelTextColor = labelTextColor;
}
/**
* Sets the label text size.
*
* @param labelTextSize the new label text size
*/
public void setLabelTextSize(int labelTextSize) {
this.labelTextSize = AbViewUtil.scaleTextValue(mContext, labelTextSize);
}
/**
* Sets the additional item height.
*
* @param additionalItemHeight the new additional item height
*/
public void setAdditionalItemHeight(int additionalItemHeight) {
this.additionalItemHeight = additionalItemHeight;
}
/**
* Wheel scrolled listener interface.
*
* @see AbOnWheelScrollEvent
*/
public interface AbOnWheelScrollListener {
/**
* Callback method to be invoked when scrolling started.
* @param wheel the wheel view whose state has changed.
*/
void onScrollingStarted(AbWheelView wheel);
/**
* Callback method to be invoked when scrolling ended.
* @param wheel the wheel view whose state has changed.
*/
void onScrollingFinished(AbWheelView wheel);
}
/**
* Wheel changed listener interface.
* <p>The currentItemChanged() method is called whenever current wheel positions is changed:
* <li> New Wheel position is set
* <li> Wheel view is scrolled
*
* @see AbOnWheelChangedEvent
*/
public interface AbOnWheelChangedListener {
/**
* Callback method to be invoked when current item changed.
*
* @param wheel the wheel view whose state has changed
* @param oldValue the old value of current item
* @param newValue the new value of current item
*/
void onChanged(AbWheelView wheel, int oldValue, int newValue);
}
}