滚动选择器
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public class Constants {
public static String[] province = new String[] { "北京市", "天津市", "河北省", "山西省", "内蒙古自治区", "辽宁省", "吉林省", "黑龙江省", "上海市",
"江苏省", "浙江省", "安徽省", "福建省", "江西省", "山东省", "河南省", "湖北省", "湖南省", "广东省", "广西壮族自治区", "海南省", "重庆市", "四川省",
"贵州省", "云南省", "西藏自治区", "陕西省", "甘肃省", "青海省", "宁夏回族自治区", "新疆维吾尔自治区", "香港", "澳门", "台湾" };
public static String[][] pandc = new String[][] {
{ "东城区", "西城区", "崇文区", "宣武区", "朝阳区", "丰台区", "石景山区", "海淀区", "石头沟区", "房山区", "通州区", "顺义区", "昌平区", "大兴区",
"怀柔区", "平谷区", "密云区", "延庆区" },
{ "和平区", "河东区", "河西区", "南开区", "河北区", "红桥区", "塘沽区", "汉沽区", "大港区", "东丽区", "西青区", "津南区", "北辰区", "武清区", "宝坻区",
"宁河县", "静海县", "蓟县" },
{ "石家庄市", "唐山市", "秦皇岛市", "邯郸市", "邢台市", "保定市", "张家口市", "承德市", "沧州市", "廊坊市", "衡水市" },
{ "太原市", "大同市", "阳泉市", "长治市", "晋城市", "朔州市", "晋中市", "运城市", "忻州市", "临汾市", "吕梁市" },
{ "呼和浩特市", "包头市", "乌海市", "赤峰市", "通辽市", "鄂尔多斯市", "呼伦贝尔市", "巴彦淖尔市", "乌兰察布市", "兴安盟", "锡林郭勒市", "阿拉善盟" },
{ "沈阳市", "大连市", "鞍山市", "抚顺市", "本溪市", "丹东市", "锦州市", "营口市", "阜新市", "辽阳市", "盘锦市", "铁岭市", "朝阳市", "葫芦岛市" },
{ "长春市", "吉林市", "四平市", "辽源市", "白山市", "松原市", "白城市", "延边州" },
{ "哈尔滨市", "齐齐哈尔市", "鸡西市", "鹤岗市", "双鸭山市", "大庆市", "伊春市", "佳木斯市", "七台河市", "牡丹江市", "黑河市", "绥化市", "大兴安岭地区" },
{ "黄浦区", "卢湾区", "徐汇区", "长宁区", "静安区", "普陀区", "闸北区", "虹口区", "杨浦区", "闵行区", "宝山区", "嘉定区", "浦东新区", "金山区", "松江区",
"青浦区", "南汇区", "奉贤区", "崇明县" },
{ "南京市", "无锡市", "徐州市", "常州市", "苏州市", "南通市", "连云港市", "淮安市", "盐城市", "扬州市", "镇江市", "泰州市", "宿迁市" },
{ "杭州市", "宁波市", "温州市", "嘉兴市", "湖州市", "绍兴市", "金华市", "衢州市", "舟山市", "台州市", "丽水市" },
{ "合肥市", "芜湖市", "蚌埠市", "淮南市", "铜陵市", "安庆市", "黄山市", "滁州市", "阜阳市", "宿州市", "巢湖市", "六安市", "亳州市", "池州市", "宣城市" },
{ "福州市", "厦门市", "莆田市", "三明市", "泉州市", "漳州市", "南平市", "龙岩市", "宁德市" },
{ "南昌市", "景德镇市", "萍乡市", "九江市", "新余市", "鹰潭市", "赣州市", "吉安市", "宜春市", "抚州市", "上饶市" },
{ "济南市", "青岛市", "淄博市", "枣庄市", "东营市", "烟台市", "廊坊市", "济宁市", "泰安市", "威海市", "照市", "莱芜市", "临沂市", "德州市", "聊城市",
"滨州市", "菏泽市" },
{ "郑州市", "开封市", "洛阳市", "平顶山市", "安阳市", "鹤壁市", "新乡市", "焦作市", "濮阳市", "许昌市", "漯河市", "三峡门市", "南阳市", "南丘市",
"信阳市", "周口市", "驻马店市" },
{ "武汉市", "黄石市", "十堰市", "宜昌市", "襄樊市", "鄂州市", "荆门市", "孝感市", "荆州市", "黄冈市", "咸宁市", "随州市", "恩施市", "仙桃市", "潜江市",
"天门市", "神农架林区" },
{ "长沙市", "株洲市", "湘潭市", "衡阳市", "邵阳市", "岳阳市", "常德市", "张家界市", "益阳市", "郴州市", "永州市", "怀化市", "娄底市", "湘西市" },
{ "广州市", "韶关市", "深圳市", "珠海市", "汕头市", "佛山市", "江门市", "湛江市", "茂名市", "肇庆市", "惠州市", "梅州市", "汕尾市", "河源市", "阳江市",
"清远市", "东莞市", "中山市", "潮州市", "揭阳市", "云浮市" },
{ "南宁市", "柳州市", "桂林市", "梧州市", "北海市", "防城港市", "钦州市", "贵港市", "玉林市", "百色市", "贺州市", "河池市", "来宾市", "崇左市" },
{ "海口市", "三亚市", "五指山市", "琼海市", "儋州市", "文昌市", "万宁市", "东方市", "安定县", "屯昌县", "澄迈县", "临高县", "白沙县", "昌江县", "乐东县",
"陵水县", "保亭县", "琼中县", "西沙群岛", "南沙群岛", "中沙群岛" },
{ "万州区", "涪陵区", "渝中区", "大渡口区", "江北区", "沙坪坝区", "九龙坡区", "南岸区", "北碚区", "万盛区", "双桥区", "渝北区", "巴南区", "黔江区",
"长寿区", "江津区", "合川区", "永川区", "南川区", "綦江县", "潼南县", "铜梁县", "大足县", "荣昌县", "璧山县", "梁平县", "城口县", "丰都县",
"垫江县", "武隆县", "忠县", "开县", "云阳县", "奉节县", "巫山县", "巫溪县", "石柱县", "秀山县" },
{ "成都市", "自贡市", "攀枝花市", "泸州市", "德阳市", "绵阳市", "广元市", "遂宁市", "内江市", "乐山市", "南充市", "眉山市", "宜宾市", "广安市", "达州市",
"雅安市", "巴中市", "资阳市", "阿坝州", "甘孜州", "凉山州" },
{ "贵阳市", "六盘水市", "遵义市", "安顺市", "铜仁地区", "黔西南州", "毕节地区", "黔东南州", "黔南州" },
{ "昆明市", "曲靖市", "玉溪市", "保山市", "昭通市", "丽江市", "普洱市", "临沧市", "文山州", "红河州", "西双版纳州", "楚雄州", "大理州", "德宏州",
"怒江州", "迪庆州" },
{ "拉萨市", "昌都地区", "山南地区", "喀则地区", "那曲地区", "阿里地区", "林芝地区" },
{ "西安市", "铜川市", "宝鸡市", "咸阳市", "渭南市", "延安市", "汉中市", "榆林市", "安康市", "南洛市" },
{ "兰州市", "嘉峪关市", "金昌市", "白银市", "天水市", "武威市", "张掖市", "平凉市", "酒泉市", "庆阳市", "定西市", "陇南市", "临夏州", "甘南州" },
{ "西宁市", "海东地区", "海北州", "黄南州", "海南州", "果洛州", "玉树州", "海西州" },
{ "银川市", "石嘴山市", "吴忠市", "固原市", "中卫市" },
{ "乌鲁木齐市", "克拉玛依市", "吐鲁番地区", "哈密地区", "昌吉州", "博尔塔拉州", "巴音郭楞州", "阿克苏地区", "克孜勒苏州", "喀什地区", "和田地区", "伊犁州",
"塔城地区", "阿勒泰地区", "石河子市", "阿拉尔市", "图木舒克", "五家渠市" }, { "香港" }, { "澳门" }, { "台湾" } };
}public class MainActivity extends Activity {
PickerView minute_pv;
PickerView second_pv;
List<String> province = new ArrayList<String>();
List<String> province0 = new ArrayList<String>();
ArrayList<ArrayList<String>> cityList = new ArrayList<ArrayList<String>>();
String provinceString = "湖南省";
String cityString = "张家界市";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
minute_pv = (PickerView) findViewById(R.id.minute_pv);
second_pv = (PickerView) findViewById(R.id.second_pv);
Collections.addAll(province, Constants.province);
Collections.addAll(province0, Constants.province);
for (int i = 0; i < Constants.pandc.length; i++) {
ArrayList<String> list2 = new ArrayList<String>();
for (int j = 0; j < Constants.pandc[i].length; j++) {
list2.add(Constants.pandc[i][j]);
}
cityList.add(list2);
}
minute_pv.setData(province0);
minute_pv.setOnSelectListener(new onSelectListener() {
@Override
public void onSelect(String text) {
provinceString = text;
for (int i = 0; i < province.size(); i++) {
if (text.equals(province.get(i))) {
second_pv.setData(cityList.get(i));
}
}
}
});
for (int i = 0; i < province.size(); i++) {
if ("湖南省".equals(province.get(i))) {
second_pv.setData(cityList.get(i));
}
}
second_pv.setOnSelectListener(new onSelectListener() {
@Override
public void onSelect(String text) {
cityString = text;
Toast.makeText(MainActivity.this, "选择了 " + provinceString + cityString, Toast.LENGTH_SHORT).show();
}
});
}public class PickerView extends View {
public static final String TAG = "PickerView";
/**
* text之间间距和minTextSize之比
*/
public static final float MARGIN_ALPHA = 2.5f;
/**
* 自动回滚到中间的速度
*/
public static final float SPEED = 2;
private List<String> 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 = 50;
private float mMinTextSize = 40;
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 PickerView(Context context) {
super(context);
init();
}
public PickerView(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<String> datas) {
mDataList = datas;
mCurrentSelected = datas.size() / 2;
invalidate();
}
public void setSelected(int selected) {
mCurrentSelected = selected;
}
private void moveHeadToTail() {
String head = mDataList.get(0);
mDataList.remove(0);
mDataList.add(head);
}
private void moveTailToHead() {
String 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();
isInit = true;
invalidate();
}
private void init() {
timer = new Timer();
mDataList = new ArrayList<String>();
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setStyle(Style.FILL);
mPaint.setTextAlign(Align.CENTER);
mPaint.setColor(mColorText);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
// 根据index绘制view
if (isInit)
drawData(canvas);
}
private void drawData(Canvas canvas) {
mPaint.setColor(Color.GRAY); // 设置画笔颜色
mPaint.setStrokeWidth((float) 0.7); // 设置线宽
canvas.drawLine(0, mViewHeight/2 - 50, mViewWidth, mViewHeight/2 - 50, mPaint);
canvas.drawLine(0, mViewHeight/2 + 50, mViewWidth, mViewHeight/2 + 50, mPaint);
// 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.setColor(Color.parseColor("#FF7F28"));
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));
canvas.drawText(mDataList.get(mCurrentSelected), 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.setColor(Color.parseColor("#000000"));
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));
canvas.drawText(mDataList.get(mCurrentSelected + type * position), (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(String text);
}
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