package com.example.picscrollview;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import com.example.picscrollview.PickerScrollView.onSelectListener;
import com.example.test.R;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Toast;
public class MainActivity extends Activity implements OnClickListener  {
    Boolean state_pressed = true;
    private String cities[] ={"北京版", "天津版", "上海版", "重庆版", "河北版", "山西版", "辽宁版", "吉林版", "黑龙江版", "江苏版", "浙江版", "安徽版",
            "福建版", "江西版", "山东版", "河南版", "湖北版", "湖南版", "广东版", "甘肃版", "四川版", "贵州版", "海南版", "云南版",
            "青海版", "陕西版", "广西版", "西藏版", "宁夏版", "新疆版", "内蒙古版", "澳门版", "香港版", "台湾版","全国版"}; 
    private String[] id = { "1", "2", "3", "4", "5", "6" ,"7","8","9","10","11","12","13","14","15","16", 
            "17", "18", "19", "20", "21", "22" ,"23","24","25","26","27","28","29","30","31","32","33","34","35"};
    private PickerScrollView pickerscrlllview; // 滚动选择器
    private List<Pickers> list; // 滚动选择器数据
    private CharacterParser mCharacterParser;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();
        initData();
    public void initView() {
        LetterSideBar letterSideBar = (LetterSideBar) findViewById(R.id.cs_letter_sb);
        letterSideBar
                .setOnTouchingLetterChangedListener(new LetterSideBar.OnTouchingLetterChangedListener() {
                    @Override
                    public void onTouchingLetterChanged(String letter) {
                        int jumpPos = getPositionForSection(letter.charAt(0));
                        pickerscrlllview.setSelected(jumpPos);
        pickerscrlllview = (PickerScrollView) findViewById(R.id.pickerscrlllview);
        pickerscrlllview.setOnSelectListener(pickerListener);
        findViewById(R.id.location_confirm_btn).setOnClickListener(this);
    private void initData() {
        mCharacterParser = CharacterParser.getInstance();
        list = filledData();
        PinyinComparator pinyinComparator = new PinyinComparator();
        Collections.sort(list, pinyinComparator);
        pickerscrlllview.setData(list);
        pickerscrlllview.setSelected(0);
    @Override
    protected void onResume() {
        super.onResume();
    public void onPause() {
        super.onPause();
     private List<Pickers> filledData() {
            List<Pickers>  sortList = new ArrayList<Pickers>();
            for (int i = 0, n = cities.length; i < n; i++) {
                Pickers picker = new Pickers();
                picker.setShowConetnt(cities[i]);
                picker.setShowId(id[i]);
                String pinyin = mCharacterParser.getSelling(cities[i]);
                picker.setPinyin(pinyin);
                String sortString = pinyin.substring(0, 1).toUpperCase();
                if (sortString.matches("[A-Z]")) {
                    picker.setSortLetter(sortString.toUpperCase());
                } else {
                    picker.setSortLetter("#");
                sortList.add(picker);
            return sortList;
        public int getPositionForSection(int section) {
            for (int i = 0; i < list.size(); i++) {
                String sortStr = list.get(i).getSortLetter();
                char firstChar = sortStr.toUpperCase().charAt(0);
                if (firstChar == section) {
                    return i;
            return -1;
    onSelectListener pickerListener = new onSelectListener() {
        @Override
        public void onSelect(Pickers pickers) {
            Toast.makeText(MainActivity.this, pickers.getShowConetnt(), Toast.LENGTH_LONG).show();
    @Override
    public void onBackPressed() {
        super.onBackPressed();
    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        default:
            break;
}

package com.example.picscrollview;
import java.util.ArrayList;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;
import com.example.test.R;
import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Paint.Align;
import android.graphics.Paint.FontMetricsInt;
import android.graphics.Paint.Style;
import android.os.Handler;
import android.os.Message;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
 * 自定义滚动选择器
 * @author zlw
@SuppressLint({ "HandlerLeak", "ClickableViewAccessibility" })
public class PickerScrollView extends View {
    public static final String TAG = "PickerView";
     * text之间间距和minTextSize之比
    public static final float MARGIN_ALPHA = 2.8f;
     * 自动回滚到中间的速度
    public static final float SPEED = 2;
    private List<Pickers> mDataList;
     * 选中的位置，这个位置是mDataList的中心位置，一直不变
    private int mCurrentSelected;
    private Paint mPaint;
    private float mMaxTextSize = 14;
    private float mMinTextSize = 6;
    private float mMaxTextAlpha = 255;
    private float mMinTextAlpha = 120;
    private int mColorText = 0x333333;
    private int mViewHeight;
    private int mViewWidth;
    private float mLastDownY;
     * 滑动的距离
    private float mMoveLen = 0;
    private boolean isInit = false;
    private onSelectListener mSelectListener;
    private Timer timer;
    private MyTimerTask mTask;
    Handler updateHandler = new Handler() {
        @Override
        public void handleMessage(Message msg) {
            if (Math.abs(mMoveLen) < SPEED) {
                mMoveLen = 0;
                if (mTask != null) {
                    mTask.cancel();
                    mTask = null;
                    performSelect();
            } else
                // 这里mMoveLen / Math.abs(mMoveLen)是为了保有mMoveLen的正负号，以实现上滚或下滚
                mMoveLen = mMoveLen - mMoveLen / Math.abs(mMoveLen) * SPEED;
            invalidate();
    public PickerScrollView(Context context) {
        super(context);
        init();
    public PickerScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    public void setOnSelectListener(onSelectListener listener) {
        mSelectListener = listener;
    private void performSelect() {
        if (mSelectListener != null)
            mSelectListener.onSelect(mDataList.get(mCurrentSelected));
    public void setData(List<Pickers> datas) {
        mDataList = datas;
        mCurrentSelected = datas.size() / 2;
        invalidate();
     * 选择选中的item的index
     * @param selected
    public void setSelected(int selected) {
        mCurrentSelected = selected;
        int distance = mDataList.size() / 2 - mCurrentSelected;
        if (distance < 0)
            for (int i = 0; i < -distance; i++) {
                moveHeadToTail();
                mCurrentSelected--;
        else if (distance > 0)
            for (int i = 0; i < distance; i++) {
                moveTailToHead();
                mCurrentSelected++;
        invalidate();
     * 选择选中的内容
     * @param mSelectItem
    public void setSelected(String mSelectItem) {
        for (int i = 0; i < mDataList.size(); i++)
            if (mDataList.get(i).equals(mSelectItem)) {
                setSelected(i);
                break;
    private void moveHeadToTail() {
        Pickers head = mDataList.get(0);
        mDataList.remove(0);
        mDataList.add(head);
    private void moveTailToHead() {
        Pickers tail = mDataList.get(mDataList.size() - 1);
        mDataList.remove(mDataList.size() - 1);
        mDataList.add(0, tail);
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        mViewHeight = getMeasuredHeight();
        mViewWidth = getMeasuredWidth();
        // 按照View的高度计算字体大小
        mMaxTextSize = mViewHeight / 8.0f;
        mMinTextSize = mMaxTextSize / 2f;
        isInit = true;
        invalidate();
    private void init() {
        timer = new Timer();
        mDataList = new ArrayList<Pickers>();
        mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
        mPaint.setStyle(Style.FILL);
        mPaint.setTextAlign(Align.CENTER);
        mPaint.setColor(getResources().getColor(R.color.white));
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        // 根据index绘制view
        if (isInit)
            drawData(canvas);
    private void drawData(Canvas canvas) {
        // 先绘制选中的text再往上往下绘制其余的text
        float scale = parabola(mViewHeight / 4.0f, mMoveLen);
        float size = (mMaxTextSize - mMinTextSize) * scale + mMinTextSize;
        mPaint.setTextSize(size);
        mPaint.setAlpha((int) ((mMaxTextAlpha - mMinTextAlpha) * scale + mMinTextAlpha));
        // text居中绘制，注意baseline的计算才能达到居中，y值是text中心坐标
        float x = (float) (mViewWidth / 2.0);
        float y = (float) (mViewHeight / 2.0 + mMoveLen);
        FontMetricsInt fmi = mPaint.getFontMetricsInt();
        float baseline = (float) (y - (fmi.bottom / 2.0 + fmi.top / 2.0));
        int indexs = mCurrentSelected;
        String textData = mDataList.get(indexs).getShowConetnt();
        canvas.drawText(textData, x, baseline, mPaint);
        // 绘制上方data
        for (int i = 1; (mCurrentSelected - i) >= 0; i++) {
            drawOtherText(canvas, i, -1);
        // 绘制下方data
        for (int i = 1; (mCurrentSelected + i) < mDataList.size(); i++) {
            drawOtherText(canvas, i, 1);
     * @param canvas
     * @param position
     *            距离mCurrentSelected的差值
     * @param type
     *            1表示向下绘制，-1表示向上绘制
    private void drawOtherText(Canvas canvas, int position, int type) {
        float d = (float) (MARGIN_ALPHA * mMinTextSize * position + type
                * mMoveLen);
        float scale = parabola(mViewHeight / 4.0f, d);
        float size = (mMaxTextSize - mMinTextSize) * scale + mMinTextSize;
        mPaint.setTextSize(size);
        mPaint.setAlpha((int) ((mMaxTextAlpha - mMinTextAlpha) * scale + mMinTextAlpha));
        float y = (float) (mViewHeight / 2.0 + type * d);
        FontMetricsInt fmi = mPaint.getFontMetricsInt();
        float baseline = (float) (y - (fmi.bottom / 2.0 + fmi.top / 2.0));
        int indexs = mCurrentSelected + type * position;
        String textData = mDataList.get(indexs).getShowConetnt();
        canvas.drawText(textData, (float) (mViewWidth / 2.0), baseline, mPaint);
     * 抛物线
     * @param zero
     *            零点坐标
     * @param x
     *            偏移量
     * @return scale
    private float parabola(float zero, float x) {
        float f = (float) (1 - Math.pow(x / zero, 2));
        return f < 0 ? 0 : f;
    @Override
    public boolean onTouchEvent(MotionEvent event) {
        switch (event.getActionMasked()) {
        case MotionEvent.ACTION_DOWN:
            doDown(event);
            break;
        case MotionEvent.ACTION_MOVE:
            doMove(event);
            break;
        case MotionEvent.ACTION_UP:
            doUp(event);
            break;
        return true;
    private void doDown(MotionEvent event) {
        if (mTask != null) {
            mTask.cancel();
            mTask = null;
        mLastDownY = event.getY();
    private void doMove(MotionEvent event) {
        mMoveLen += (event.getY() - mLastDownY);
        if (mMoveLen > MARGIN_ALPHA * mMinTextSize / 2) {
            // 往下滑超过离开距离
            moveTailToHead();
            mMoveLen = mMoveLen - MARGIN_ALPHA * mMinTextSize;
        } else if (mMoveLen < -MARGIN_ALPHA * mMinTextSize / 2) {
            // 往上滑超过离开距离
            moveHeadToTail();
            mMoveLen = mMoveLen + MARGIN_ALPHA * mMinTextSize;
        mLastDownY = event.getY();
        invalidate();
    private void doUp(MotionEvent event) {
        // 抬起手后mCurrentSelected的位置由当前位置move到中间选中位置
        if (Math.abs(mMoveLen) < 0.0001) {
            mMoveLen = 0;
            return;
        if (mTask != null) {
            mTask.cancel();
            mTask = null;
        mTask = new MyTimerTask(updateHandler);
        timer.schedule(mTask, 0, 10);
    class MyTimerTask extends TimerTask {
        Handler handler;
        public MyTimerTask(Handler handler) {
            this.handler = handler;
        @Override
        public void run() {
            handler.sendMessage(handler.obtainMessage());
    public interface onSelectListener {
        void onSelect(Pickers pickers);
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