Android自定義RecyclerView實現不固定刻度的刻度尺
阿新 • • 發佈：2020-07-17
本文例項為大家分享了自定義RecyclerView實現不固定刻度的刻度尺的具體程式碼，供大家參考，具體內容如下
##不均勻刻度效果圖
##等比例刻度效果圖
實現功能目前
1、實現類似日期/分類等大小不固定的水平刻度尺效果
2、實現標準刻度尺效果
3、監聽RecyclerView滑動時居中條目
4、去掉邊緣陰影
定義RecyclerView
public class CenterRecyclerView extends RecyclerView {
//設定RecyclerView的速度
private static final int MAXIMUM_FLING_VELOCITY = 3000;
//畫中軸線
private Paint mCenterLinePaint;
private Context context;
private CenterLayoutManager mLayoutManager;
private Paint mTextPaint;
private String text = "";
private String textUnit = "";
private Paint mTextUnitPaint;
private int mWidth;
private int mHeight;
private int mLineStartY;
private int mLineEndY;
private int mTextStartY;
public CenterRecyclerView(@NonNull Context context) {
this(context,null);
}
public CenterRecyclerView(@NonNull Context context,@Nullable AttributeSet attrs) {
this(context,attrs,-1);
}
public CenterRecyclerView(@NonNull Context context,@Nullable AttributeSet attrs,int defStyleAttr) {
super(context,defStyleAttr);
init(context,attrs);
}
private void init(Context context,AttributeSet attrs) {
this.context = context;
initPaint();
}
public void setTypeface(Typeface typeface) {
mTextPaint.setTypeface(typeface);
mTextUnitPaint.setTypeface(typeface);
}
private void initPaint() {
mCenterLinePaint = new Paint();
mCenterLinePaint.setAntiAlias(true);
mCenterLinePaint.setStrokeWidth(ScreenUtil.dip2px(context,4));
mCenterLinePaint.setTextAlign(Paint.Align.CENTER);
mCenterLinePaint.setColor(0xff6e9fff);
mTextUnitPaint = new Paint();
mTextUnitPaint.setStyle(Paint.Style.FILL);
mTextUnitPaint.setStrokeWidth(ScreenUtil.dip2px(context,4));
mTextUnitPaint.setTextSize(ScreenUtil.dip2px(context,15));
mTextUnitPaint.setColor(Color.parseColor("#DD5F00"));
mTextPaint = new Paint();
mTextPaint.setStyle(Paint.Style.FILL);
mTextPaint.setStrokeWidth(ScreenUtil.dip2px(context,4));
mTextPaint.setTextSize(ScreenUtil.dip2px(context,60));
mTextPaint.setColor(Color.parseColor("#DD5F00"));
mTextPaint.setTextAlign(Paint.Align.CENTER);
}
@Override
public void addOnScrollListener(@NonNull OnScrollListener listener) {
super.addOnScrollListener(listener);
postInvalidate();
}
@Override
protected void onMeasure(int widthSpec,int heightSpec) {
super.onMeasure(widthSpec,heightSpec);
}
//獲取相關引數
@Override
protected void onLayout(boolean changed,int l,int t,int r,int b) {
super.onLayout(changed,l,t,r,b);
mWidth = getWidth();
mHeight = getHeight();
int lineHeight = ScreenUtil.dip2px(context,58);
mLineStartY = mHeight / 2 - lineHeight / 2;
mLineEndY = mHeight / 2 + lineHeight / 2;
mTextStartY = mHeight / 2 - ScreenUtil.dip2px(context,55);
}
@Override
public void draw(Canvas c) {
super.draw(c);
Log.d("szjjyh","draw: " + getWidth());
drawCenterLine(c);
drawText(c);
}
//畫線
private void drawCenterLine(Canvas canvas) {
canvas.drawLine(mWidth / 2,mLineStartY,mWidth / 2,mLineEndY,mCenterLinePaint);
}
//畫字/畫單位
private void drawText(Canvas c) {
c.drawText(text,mTextStartY,mTextPaint);
if (textUnit != null && textUnit.length() != 0) {
float textWidth = mTextPaint.measureText(text);
c.drawText(textUnit,(mWidth + textWidth) / 2,mTextUnitPaint);
}
}
public String getText() {
return text;
}
public void setText(String text) {
if (text == null) {
return;
}
this.text = text;
}
public String getTextUnit() {
return textUnit;
}
public void setTextUnit(String textUnit) {
if (textUnit == null) {
return;
}
this.textUnit = textUnit;
}
@Override
public void setAdapter(@Nullable Adapter adapter) {
super.setAdapter(adapter);
}
@Override
public void setLayoutManager(@Nullable LayoutManager layout) {
super.setLayoutManager(layout);
mLayoutManager = (CenterLayoutManager) layout;
}
@Override
public boolean fling(int velocityX,int velocityY) {
velocityX = solveVelocity(velocityX);
velocityY = solveVelocity(velocityY);
return super.fling(velocityX,velocityY);
}
private int solveVelocity(int velocity) {
if (velocity > 0) {
return Math.min(velocity,MAXIMUM_FLING_VELOCITY);
} else {
return Math.max(velocity,-MAXIMUM_FLING_VELOCITY);
}
}
// @Override
// protected float getLeftFadingEdgeStrength() {
// return 0;
// }
}定義LinearLayoutManager
public class CenterLayoutManager extends LinearLayoutManager {
public CenterLayoutManager(Context context) {
super(context);
}
public CenterLayoutManager(Context context,int orientation,boolean reverseLayout) {
super(context,orientation,reverseLayout);
}
public CenterLayoutManager(Context context,AttributeSet attrs,int defStyleAttr,int defStyleRes) {
super(context,defStyleAttr,defStyleRes);
}
//計算偏移量自己適配
@Override
public void scrollToPosition(int position) {
scrollToPositionWithOffset(position,-15);
}
@Override
public void scrollToPositionWithOffset(int position,int offset) {
super.scrollToPositionWithOffset(position,offset);
}
@Override
public void smoothScrollToPosition(RecyclerView recyclerView,RecyclerView.State state,int position) {
RecyclerView.SmoothScroller smoothScroller = new CenterSmoothScroller(recyclerView.getContext());
smoothScroller.setTargetPosition(position);
startSmoothScroll(smoothScroller);
}
public void smoothScrollToPosition(RecyclerView recyclerView,int position) {
RecyclerView.SmoothScroller smoothScroller = new CenterSmoothScroller(recyclerView.getContext());
smoothScroller.setTargetPosition(position);
startSmoothScroll(smoothScroller);
}
private static class CenterSmoothScroller extends LinearSmoothScroller {
CenterSmoothScroller(Context context) {
super(context);
}
//滑動到中間位置
@Override
public int calculateDtToFit(int viewStart,int viewEnd,int boxStart,int boxEnd,int snapPreference) {
return (boxStart + (boxEnd - boxStart) / 2) - (viewStart + (viewEnd - viewStart) / 2);
}
//滾動速度設定
@Override
protected float calculateSpeedPerPixel(DisplayMetrics displayMetrics) {
return 4;
}
@Override
protected int getVerticalSnapPreference() {
return super.getVerticalSnapPreference();
}
}
}滑動事件監聽
public class CenterScrollListener extends RecyclerView.OnScrollListener {
private CenterLayoutManager mLayoutManager;
RecyclerView recyclerView;
private int mPosition;
private double intScrollState;
private int mFirstItemPosition1;
private int mLastItemPosition1;
private boolean is_Stop;
private String TAG = "CenterScrollListener";
private double is_playSound;
public CenterScrollListener(OnItemCenterScrollistner onItemCenterScrollistner) {
this.onItemCenterScrollistner = onItemCenterScrollistner;
}
public void onScrollStateChanged(@NonNull RecyclerView recyclerView,int newState) {
init(recyclerView);
intScrollState = newState;
is_Stop = false;
if (intScrollState == RecyclerView.SCROLL_STATE_IDLE) {
Log.e(TAG,"onScrollStateChanged: 11111:"+mPosition);
CeterScroll(0,mPosition);
}
}
public void onScrolled(@NonNull RecyclerView recyclerView,int dx,int dy) {
init(recyclerView);
int x = Math.abs(dx);
if (!is_Stop && x <= 1) {
is_Stop = true;
if (dx >= 0) {
mPosition = (mFirstItemPosition1 + mLastItemPosition1) / 2;
View childAt = mLayoutManager.findViewByPosition(mPosition);
if (childAt.getLeft() < ScreenUtil.getScreenWidth(recyclerView.getContext()) / 2) {
mPosition = mPosition + 1;
}
Log.e(TAG,"111111: w:" + childAt.getWidth() + " :l:" +
childAt.getLeft() + " :r:" + childAt.getRight());
} else {
mPosition = (mFirstItemPosition1 + mLastItemPosition1) / 2;
View childAt = mLayoutManager.findViewByPosition(mPosition);
if (childAt.getLeft() > ScreenUtil.getScreenWidth(recyclerView.getContext()) / 2) {
mPosition = mPosition - 1;
}
}
}
CeterScroll(x,mPosition);
}
//事件監聽
private void init(@NonNull RecyclerView recyclerView) {
this.recyclerView = recyclerView;
if (mLayoutManager == null) {
mLayoutManager = (CenterLayoutManager) recyclerView.getLayoutManager();
}
int firstItemPosition = mLayoutManager.findFirstVisibleItemPosition();
int lastItemPosition = mLayoutManager.findLastVisibleItemPosition();
mFirstItemPosition1 = mLayoutManager.findFirstCompletelyVisibleItemPosition();
mLastItemPosition1 = mLayoutManager.findLastCompletelyVisibleItemPosition();
mPosition = (mFirstItemPosition1 + mLastItemPosition1) / 2;
if (is_playSound != mPosition) {
is_playSound = mPosition;
int count = mLayoutManager.getItemCount();
// soundpool.play(soundmap.get(1),1,1);
if (onItemCenterScrollistner != null) {
//中間條目事件監聽
onItemCenterScrollistner.onItemCenterScrollistner(mLastItemPosition1,mPosition,count);
}
}
//目前由於要實現灰色條目當條目間距為10dp,螢幕寬度360時不能繼續滑動
if (mPosition <= 18) {
CeterScroll(0,18);
}
}
//速度變小時自動滾動到中間位置
private void CeterScroll(int dx,int position) {
if ((intScrollState == RecyclerView.SCROLL_STATE_SETTLING || intScrollState
== RecyclerView.SCROLL_STATE_IDLE) && Math.abs(dx) <= 1) {
mLayoutManager.smoothScrollToPosition(recyclerView,position);
}
}
OnItemCenterScrollistner onItemCenterScrollistner;
public void setOnItemCenterScrollistner(OnItemCenterScrollistner onItemCenterScrollistner) {
this.onItemCenterScrollistner = onItemCenterScrollistner;
}
public interface OnItemCenterScrollistner {
void onItemCenterScrollistner(int lastItemPosition1,int position,int count);
}adpater實現
public class DateAdapter extends BaseRecyclerAdapter<CalendarDateBean> {
private static final int layoutId = R.layout.view_item_date;
public DateAdapter(Context context,List<CalendarDateBean> datas) {
super(context,datas,layoutId);
}
@Override
protected void bindData(BaseViewHolder holder,CalendarDateBean data,int position) {
if (data.getDay() == 1) {
//R.id.tv_1為線需要居中否則和中軸線不會完全對稱 R.id.tv_2為大刻度文字
holder.getView(R.id.tv_1).setScaleX(2F);
holder.setText(R.id.tv_2,data.getMonth() + "月");
holder.getView(R.id.tv_2).setVisibility(View.VISIBLE);
holder.getView(R.id.tv_1).setBackgroundColor(Color.parseColor("#ffffff"));
} else if (data.getDay() ==-1){
holder.getView(R.id.tv_1).setScaleX(1F);
holder.getView(R.id.tv_2).setVisibility(View.GONE);
holder.getView(R.id.tv_1).setBackgroundColor(Color.parseColor("#222222"));
}else {
holder.getView(R.id.tv_1).setScaleX(1F);
holder.getView(R.id.tv_2).setVisibility(View.GONE);
holder.getView(R.id.tv_1).setBackgroundColor(Color.parseColor("#ffffff"));
}
}
}
activity 載入view展示
private void initRecyclerView() {
//此處試配時注意item10dp 寬度360 計算髮放 360/10/2得到記得適配
for (int i = 0; i < 18; i++) {
TimeBean timeBean = new TimeBean();
mList.add(timeBean);
}
for (int i = 0; i < 1440; i++) {
int minute = i % 60;
int hour = i / 60;
if (CalendarUtil.getHourTime()==hour&&CalendarUtil.getMinuteTime()==minute){
mPostion = i;
}
TimeBean timeBean = new TimeBean();
timeBean.setHour(hour);
timeBean.setMinute(minute);
timeBean.setTimeDate(CalendarUtil.getHourToMinute(hour,minute));
mList.add(timeBean);
}
for (int i = 0; i < 18; i++) {
TimeBean timeBean = new TimeBean();
// timeBean.setMinute(-1);
mList.add(timeBean);
}
rv_data = findViewById(R.id.rv_data);
mAdapter = new TimeAdapter(this,mList);
rv_data.setAdapter(mAdapter);
//設定字型
rv_data.setTypeface(Typeface.createFromAsset(getAssets(),"fonts/dincond_boldalternate.ttf"));
CenterLayoutManager layoutManager = new CenterLayoutManager(this);
layoutManager.setOrientation(LinearLayoutManager.HORIZONTAL);
rv_data.setLayoutManager(layoutManager);
rv_data.scrollToPosition(mPostion);
rv_data.addOnScrollListener(new CenterScrollListener((lastItemPosition,position,count) -> {
//更新文字和單位
rv_data.setText(mList.get(position).getTimeDate());
if (mList.get(position).getHour()>12){
rv_data.setTextUnit("PM");
}else {
rv_data.setTextUnit("AM");
}
}));
}
實現了基本程式碼全部寫了。
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支援我們。