本文實例為大家分享了自定義RecyclerView實現不固定刻度的刻度尺的具體代碼，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 {//設置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, attrs, 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); }//獲取相關參數 @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, mWidth / 2, mTextStartY, mTextPaint); if (textUnit != null && textUnit.length() != 0) { float textWidth = mTextPaint.measureText(text); c.drawText(textUnit, (mWidth + textWidth) / 2, mTextStartY, 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, attrs, 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); }//滾動速度設置 @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, 0, 0, 1); if (onItemCenterScrollistner != null) {//中間條目事件監聽 onItemCenterScrollistner.onItemCenterScrollistner(mLastItemPosition1, mPosition,count); } }//目前由于要實現灰色條目當條目間距為10dp,屏幕寬度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 加載view展示

private void initRecyclerView() {//此處試配時注意item10dp 寬度360 計算發放 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);//設置字體 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) -> {//更新文本和單位 rv_data.setText(mList.get(position).getTimeDate()); if (mList.get(position).getHour()>12){ rv_data.setTextUnit('PM'); }else { rv_data.setTextUnit('AM'); } })); }

實現了基本代碼全部寫了。

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持好吧啦網。