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/* * Copyright (c) 2016. by Hoang Hiep (hoanghiep8899@gmail.com) * This file FastScroller.java is part of File Manager * Create at 3/6/16 2:19 PM * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package com.filemanager.free.ui.views; import android.content.Context; import android.content.res.TypedArray; import android.graphics.drawable.ColorDrawable; import android.graphics.drawable.Drawable; import android.graphics.drawable.InsetDrawable; import android.graphics.drawable.StateListDrawable; import android.support.annotation.AttrRes; import android.support.annotation.NonNull; import android.support.v4.content.ContextCompat; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.RecyclerView.OnScrollListener; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.View; import android.widget.FrameLayout; import android.widget.ImageView; import com.filemanager.free.R; import com.filemanager.free.utils.Futils; public class FastScroller extends FrameLayout { private View bar; private ImageView handle; private RecyclerView recyclerView; private final ScrollListener scrollListener; boolean manuallyChangingPosition = false; int columns = 1; class ScrollListener extends OnScrollListener { private ScrollListener() { } public void onScrolled(RecyclerView recyclerView, int i, int i2) { if (handle != null && !manuallyChangingPosition) { updateHandlePosition(); } } } public FastScroller(@NonNull Context context, AttributeSet attributeSet) { super(context, attributeSet); this.scrollListener = new ScrollListener(); initialise(context); } public FastScroller(@NonNull Context context, AttributeSet attributeSet, int i) { super(context, attributeSet, i); this.scrollListener = new ScrollListener(); initialise(context); } private float computeHandlePosition() { View firstVisibleView = recyclerView.getChildAt(0); handle.setVisibility(VISIBLE); float recyclerViewOversize; //how much is recyclerView bigger than fastScroller int recyclerViewAbsoluteScroll; if (firstVisibleView == null || recyclerView == null) return -1; recyclerViewOversize = firstVisibleView.getHeight() / columns * recyclerView.getAdapter().getItemCount() - getHeightMinusPadding(); recyclerViewAbsoluteScroll = recyclerView.getChildLayoutPosition(firstVisibleView) / columns * firstVisibleView.getHeight() - firstVisibleView.getTop(); return recyclerViewAbsoluteScroll / recyclerViewOversize; } private int getHeightMinusPadding() { return (getHeight() - getPaddingBottom()) - getPaddingTop(); } private void initialise(@NonNull Context context) { setClipChildren(false); inflate(context, R.layout.fastscroller, this); this.handle = (ImageView) findViewById(R.id.scroll_handle); this.bar = findViewById(R.id.scroll_bar); this.handle.setEnabled(true); setPressedHandleColor(getResources().getColor(R.color.accent_blue)); setUpBarBackground(); setVisibility(VISIBLE); } private void setHandlePosition1(float relativePos) { handle.setY(Futils.getValueInRange(0, getHeightMinusPadding() - handle.getHeight(), relativePos * (getHeightMinusPadding() - handle.getHeight()))); } private void setUpBarBackground() { InsetDrawable insetDrawable; int resolveColor = resolveColor(getContext(), R.attr.colorControlNormal); insetDrawable = new InsetDrawable(new ColorDrawable(resolveColor), getResources().getDimensionPixelSize(R.dimen.fastscroller_track_padding), 0, 0, 0); this.bar.setBackgroundDrawable(insetDrawable); } int resolveColor(@NonNull Context context, @AttrRes int i) { TypedArray obtainStyledAttributes = context.obtainStyledAttributes(new int[] { i }); int color = obtainStyledAttributes.getColor(0, 0); obtainStyledAttributes.recycle(); return color; } onTouchListener a; public boolean onTouchEvent(@NonNull MotionEvent motionEvent) { if (motionEvent.getAction() == 0 || motionEvent.getAction() == 2) { this.handle.setPressed(true); bar.setVisibility(VISIBLE); float relativePos = getRelativeTouchPosition(motionEvent); setHandlePosition1(relativePos); manuallyChangingPosition = true; setRecyclerViewPosition(relativePos); // showIfHidden(); if (a != null) a.onTouch(); return true; } else if (motionEvent.getAction() != 1) { return super.onTouchEvent(motionEvent); } else { bar.setVisibility(INVISIBLE); manuallyChangingPosition = false; this.handle.setPressed(false); // scheduleHide(); return true; } } private void invalidateVisibility() { if (recyclerView.getAdapter() == null || recyclerView.getAdapter().getItemCount() == 0 || recyclerView.getChildAt(0) == null || isRecyclerViewScrollable()) { setVisibility(INVISIBLE); } else { setVisibility(VISIBLE); } } private boolean isRecyclerViewScrollable() { return recyclerView.getChildAt(0).getHeight() * recyclerView.getAdapter().getItemCount() / columns <= getHeightMinusPadding() || recyclerView.getAdapter().getItemCount() / columns < 25; } private void setRecyclerViewPosition(float relativePos) { if (recyclerView != null) { int itemCount = recyclerView.getAdapter().getItemCount(); int targetPos = (int) Futils.getValueInRange(0, itemCount - 1, (int) (relativePos * (float) itemCount)); recyclerView.scrollToPosition(targetPos); } } private float getRelativeTouchPosition(MotionEvent event) { float yInParent = event.getRawY() - Futils.getViewRawY(handle); return yInParent / (getHeightMinusPadding() - handle.getHeight()); } public interface onTouchListener { void onTouch(); } public void registerOnTouchListener(onTouchListener onTouchListener) { a = onTouchListener; } public void setPressedHandleColor(int i) { handle.setColorFilter(i); StateListDrawable stateListDrawable = new StateListDrawable(); Drawable drawable = ContextCompat.getDrawable(getContext(), R.drawable.fastscroller_handle_normal); Drawable drawable1 = ContextCompat.getDrawable(getContext(), R.drawable.fastscroller_handle_pressed); stateListDrawable.addState(View.PRESSED_ENABLED_STATE_SET, new InsetDrawable(drawable1, getResources().getDimensionPixelSize(R.dimen.fastscroller_track_padding), 0, 0, 0)); stateListDrawable.addState(View.EMPTY_STATE_SET, new InsetDrawable(drawable, getResources().getDimensionPixelSize(R.dimen.fastscroller_track_padding), 0, 0, 0)); this.handle.setImageDrawable(stateListDrawable); } public void setRecyclerView(@NonNull RecyclerView recyclerView, int columns) { this.recyclerView = recyclerView; this.columns = columns; bar.setVisibility(INVISIBLE); recyclerView.addOnScrollListener(this.scrollListener); invalidateVisibility(); recyclerView.setOnHierarchyChangeListener(new OnHierarchyChangeListener() { @Override public void onChildViewAdded(View parent, View child) { invalidateVisibility(); } @Override public void onChildViewRemoved(View parent, View child) { invalidateVisibility(); } }); } void updateHandlePosition() { setHandlePosition1(computeHandlePosition()); } int vx1 = -1; public void updateHandlePosition(int vx, int l) { if (vx != vx1) { setPadding(getPaddingLeft(), getPaddingTop(), getPaddingRight(), l + vx); setHandlePosition1(computeHandlePosition()); vx1 = vx; } } }