Java tutorial
/* * Copyright(c) 2017 lizhaotailang * * 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 io.github.marktony.espresso.component; import android.animation.Animator; import android.animation.AnimatorListenerAdapter; import android.animation.ObjectAnimator; import android.content.Context; import android.content.res.Resources; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.Point; import android.graphics.Rect; import android.graphics.Typeface; import android.support.annotation.ColorInt; import android.support.v4.content.ContextCompat; import android.support.v4.view.animation.FastOutLinearInInterpolator; import android.support.v4.view.animation.LinearOutSlowInInterpolator; import android.support.v7.widget.RecyclerView; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.View; import android.view.ViewConfiguration; import io.github.marktony.espresso.R; import io.github.marktony.espresso.interfaze.OnFastScrollStateChangeListener; import io.github.marktony.espresso.util.DensityUtil; /** * Created by lizhaotailang on 2017/3/24. */ public class FastScroller { private static final int DEFAULT_AUTO_HIDE_DELAY = 1500; private FastScrollRecyclerView mRecyclerView; private FastScrollPopup mPopup; private int mThumbHeight; private int mWidth; private Paint mThumb; private Paint mTrack; private Rect mTmpRect = new Rect(); private Rect mInvalidateRect = new Rect(); private Rect mInvalidateTmpRect = new Rect(); // The inset is the buffer around which a point will still register as a click on the scrollbar private int mTouchInset; // This is the offset from the top of the scrollbar when the user first starts touching. To // prevent jumping, this offset is applied as the user scrolls. private int mTouchOffset; private Point mThumbPosition = new Point(-1, -1); private Point mOffset = new Point(0, 0); private boolean mIsDragging; private Animator mAutoHideAnimator; private boolean mAnimatingShow; private int mAutoHideDelay = DEFAULT_AUTO_HIDE_DELAY; private boolean mAutoHideEnabled = true; private final Runnable mHideRunnable; public FastScroller(Context context, FastScrollRecyclerView recyclerView, AttributeSet attrs) { Resources resources = context.getResources(); mRecyclerView = recyclerView; mPopup = new FastScrollPopup(resources, recyclerView); mThumbHeight = DensityUtil.dip2px(context, 48); mWidth = DensityUtil.dip2px(context, 8); mTouchInset = DensityUtil.dip2px(context, -24); mThumb = new Paint(Paint.ANTI_ALIAS_FLAG); mTrack = new Paint(Paint.ANTI_ALIAS_FLAG); TypedArray typedArray = context.getTheme().obtainStyledAttributes(attrs, R.styleable.FastScrollRecyclerView, 0, 0); try { mAutoHideEnabled = typedArray.getBoolean(R.styleable.FastScrollRecyclerView_fastScrollAutoHide, true); mAutoHideDelay = typedArray.getInteger(R.styleable.FastScrollRecyclerView_fastScrollAutoHideDelay, DEFAULT_AUTO_HIDE_DELAY); int trackColor = typedArray.getColor(R.styleable.FastScrollRecyclerView_fastScrollTrackColor, 0x1f000000); int thumbColor = typedArray.getColor(R.styleable.FastScrollRecyclerView_fastScrollThumbColor, ContextCompat.getColor(context, R.color.colorPrimary)); int popupBgColor = typedArray.getColor(R.styleable.FastScrollRecyclerView_fastScrollPopupBgColor, ContextCompat.getColor(context, R.color.colorPrimary)); int popupTextColor = typedArray.getColor(R.styleable.FastScrollRecyclerView_fastScrollPopupTextColor, 0xffffffff); int popupTextSize = typedArray.getDimensionPixelSize( R.styleable.FastScrollRecyclerView_fastScrollPopupTextSize, DensityUtil.dip2sp(context, 56)); int popupBackgroundSize = typedArray.getDimensionPixelSize( R.styleable.FastScrollRecyclerView_fastScrollPopupBackgroundSize, DensityUtil.dip2px(context, 88)); mTrack.setColor(trackColor); mThumb.setColor(thumbColor); mPopup.setBgColor(popupBgColor); mPopup.setTextColor(popupTextColor); mPopup.setTextSize(popupTextSize); mPopup.setBackgroundSize(popupBackgroundSize); } finally { typedArray.recycle(); } mHideRunnable = new Runnable() { @Override public void run() { if (!mIsDragging) { if (mAutoHideAnimator != null) { mAutoHideAnimator.cancel(); } mAutoHideAnimator = ObjectAnimator.ofInt(FastScroller.this, "offsetX", (mRecyclerView.getResources().getConfiguration() .getLayoutDirection() == View.LAYOUT_DIRECTION_RTL ? -1 : 1) * mWidth); mAutoHideAnimator.setInterpolator(new FastOutLinearInInterpolator()); mAutoHideAnimator.setDuration(200); mAutoHideAnimator.start(); } } }; mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() { @Override public void onScrolled(RecyclerView recyclerView, int dx, int dy) { super.onScrolled(recyclerView, dx, dy); show(); } }); if (mAutoHideEnabled) { postAutoHideDelayed(); } } public int getThumbHeight() { return mThumbHeight; } public int getWidth() { return mWidth; } public boolean isDragging() { return mIsDragging; } /** * Handles the touch event and determines whether to show the fast scroller (or updates it if * it is already showing). */ public void handleTouchEvent(MotionEvent ev, int downX, int downY, int lastY, OnFastScrollStateChangeListener stateChangeListener) { ViewConfiguration config = ViewConfiguration.get(mRecyclerView.getContext()); int action = ev.getAction(); int y = (int) ev.getY(); switch (action) { case MotionEvent.ACTION_DOWN: if (isNearPoint(downX, downY)) { mTouchOffset = downY - mThumbPosition.y; } break; case MotionEvent.ACTION_MOVE: // Check if we should start scrolling if (!mIsDragging && isNearPoint(downX, downY) && Math.abs(y - downY) > config.getScaledTouchSlop()) { mRecyclerView.getParent().requestDisallowInterceptTouchEvent(true); mIsDragging = true; mTouchOffset += (lastY - downY); mPopup.animateVisibility(true); if (stateChangeListener != null) { stateChangeListener.onFastScrollStart(); } } if (mIsDragging) { // Update the fastscroller section name at this touch position int top = 0; int bottom = mRecyclerView.getHeight() - mThumbHeight; float boundedY = (float) Math.max(top, Math.min(bottom, y - mTouchOffset)); String sectionName = mRecyclerView.scrollToPositionAtProgress((boundedY - top) / (bottom - top)); mPopup.setSectionName(sectionName); mPopup.animateVisibility(!sectionName.isEmpty()); mRecyclerView.invalidate(mPopup.updateFastScrollerBounds(mRecyclerView, mThumbPosition.y)); } break; case MotionEvent.ACTION_UP: case MotionEvent.ACTION_CANCEL: mTouchOffset = 0; if (mIsDragging) { mIsDragging = false; mPopup.animateVisibility(false); if (stateChangeListener != null) { stateChangeListener.onFastScrollStop(); } } break; } } public void draw(Canvas canvas) { if (mThumbPosition.x < 0 || mThumbPosition.y < 0) { return; } //Background canvas.drawRect(mThumbPosition.x + mOffset.x, mThumbHeight / 2 + mOffset.y, mThumbPosition.x + mOffset.x + mWidth, mRecyclerView.getHeight() + mOffset.y - mThumbHeight / 2, mTrack); //Handle canvas.drawRect(mThumbPosition.x + mOffset.x, mThumbPosition.y + mOffset.y, mThumbPosition.x + mOffset.x + mWidth, mThumbPosition.y + mOffset.y + mThumbHeight, mThumb); //Popup mPopup.draw(canvas); } /** * Returns whether the specified points are near the scroll bar bounds. */ private boolean isNearPoint(int x, int y) { mTmpRect.set(mThumbPosition.x, mThumbPosition.y, mThumbPosition.x + mWidth, mThumbPosition.y + mThumbHeight); mTmpRect.inset(mTouchInset, mTouchInset); return mTmpRect.contains(x, y); } public void setThumbPosition(int x, int y) { if (mThumbPosition.x == x && mThumbPosition.y == y) { return; } // do not create new objects here, this is called quite often mInvalidateRect.set(mThumbPosition.x + mOffset.x, mOffset.y, mThumbPosition.x + mOffset.x + mWidth, mRecyclerView.getHeight() + mOffset.y); mThumbPosition.set(x, y); mInvalidateTmpRect.set(mThumbPosition.x + mOffset.x, mOffset.y, mThumbPosition.x + mOffset.x + mWidth, mRecyclerView.getHeight() + mOffset.y); mInvalidateRect.union(mInvalidateTmpRect); mRecyclerView.invalidate(mInvalidateRect); } private void setOffset(int x, int y) { if (mOffset.x == x && mOffset.y == y) { return; } // do not create new objects here, this is called quite often mInvalidateRect.set(mThumbPosition.x + mOffset.x, mOffset.y, mThumbPosition.x + mOffset.x + mWidth, mRecyclerView.getHeight() + mOffset.y); mOffset.set(x, y); mInvalidateTmpRect.set(mThumbPosition.x + mOffset.x, mOffset.y, mThumbPosition.x + mOffset.x + mWidth, mRecyclerView.getHeight() + mOffset.y); mInvalidateRect.union(mInvalidateTmpRect); mRecyclerView.invalidate(mInvalidateRect); } // Setter/getter for the popup alpha for animations public void setOffsetX(int x) { setOffset(x, mOffset.y); } public int getOffsetX() { return mOffset.x; } private void show() { if (!mAnimatingShow) { if (mAutoHideAnimator != null) { mAutoHideAnimator.cancel(); } mAutoHideAnimator = ObjectAnimator.ofInt(this, "offsetX", 0); mAutoHideAnimator.setInterpolator(new LinearOutSlowInInterpolator()); mAutoHideAnimator.setDuration(150); mAutoHideAnimator.addListener(new AnimatorListenerAdapter() { @Override public void onAnimationCancel(Animator animation) { super.onAnimationCancel(animation); mAnimatingShow = false; } @Override public void onAnimationEnd(Animator animation) { super.onAnimationEnd(animation); mAnimatingShow = false; } }); mAnimatingShow = true; mAutoHideAnimator.start(); } if (mAutoHideEnabled) { postAutoHideDelayed(); } else { cancelAutoHide(); } } private void postAutoHideDelayed() { if (mRecyclerView != null) { cancelAutoHide(); mRecyclerView.postDelayed(mHideRunnable, mAutoHideDelay); } } private void cancelAutoHide() { if (mRecyclerView != null) { mRecyclerView.removeCallbacks(mHideRunnable); } } public void setThumbColor(@ColorInt int color) { mThumb.setColor(color); mRecyclerView.invalidate(mInvalidateRect); } public void setTrackColor(@ColorInt int color) { mTrack.setColor(color); mRecyclerView.invalidate(mInvalidateRect); } public void setPopupBgColor(@ColorInt int color) { mPopup.setBgColor(color); } public void setPopupTextColor(@ColorInt int color) { mPopup.setTextColor(color); } public void setPopupTypeface(Typeface typeface) { mPopup.setTypeface(typeface); } public void setPopupTextSize(int size) { mPopup.setTextSize(size); } public void setAutoHideDelay(int hideDelay) { mAutoHideDelay = hideDelay; if (mAutoHideEnabled) { postAutoHideDelayed(); } } public void setAutoHideEnabled(boolean autoHideEnabled) { mAutoHideEnabled = autoHideEnabled; if (autoHideEnabled) { postAutoHideDelayed(); } else { cancelAutoHide(); } } }