Java tutorial
// Copyright (C) 2013 City of Copenhagen. // // This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. // If a copy of the MPL was not distributed with this file, You can obtain one at // http://mozilla.org/MPL/2.0/. package com.spoiledmilk.ibikecph.controls; import java.util.ArrayList; import java.util.Iterator; import android.content.Context; import android.support.v4.view.GestureDetectorCompat; import android.util.AttributeSet; import android.view.GestureDetector; import android.view.MotionEvent; import android.view.View; import android.view.animation.Animation; import android.view.animation.Animation.AnimationListener; import android.view.animation.TranslateAnimation; import android.widget.ListView; import com.spoiledmilk.ibikecph.LeftMenu; import com.spoiledmilk.ibikecph.favorites.FavoritesAdapter; import com.spoiledmilk.ibikecph.util.LOG; import com.spoiledmilk.ibikecph.util.Util; public class SortableListView extends ListView { private int firstVisibleItem = 0; private int viewIndex = 0; private int viewHeight; private FavoritesAdapter adapter; private View view = null; LeftMenu parentContainer; private int indexToAnimate = -1; private int indexToReorder = 0; boolean isDragStarted = false; ArrayList<ViewData> views; float lastY; boolean scrolling = false; int fixedPositionOffset = 0; private GestureDetectorCompat mDetector; public int srollPos = 0; private void init() { mDetector = new GestureDetectorCompat(getContext(), new MyGestureListener()); } public SortableListView(Context context) { super(context); init(); } public SortableListView(Context context, AttributeSet attrs) { super(context, attrs); init(); } public void setParentContainer(LeftMenu parentContainer) { this.parentContainer = parentContainer; } public void enableScroll() { getParent().requestDisallowInterceptTouchEvent(false); } public void disableScroll() { getParent().requestDisallowInterceptTouchEvent(true); smoothScrollToPosition(0); firstVisibleItem = 0; } @Override public boolean onTouchEvent(MotionEvent event) { mDetector.onTouchEvent(event); if ((getAdapter() != null && !(((FavoritesAdapter) getAdapter()).isEditMode)) || getAdapter() == null) { LOG.d("sortable list view super.onTouch"); return super.onTouchEvent(event); } this.adapter = (FavoritesAdapter) getAdapter(); if (event.getAction() == MotionEvent.ACTION_DOWN) { lastDistanceY = 0; views = new ArrayList<ViewData>(); for (int i = 0; i < getAdapter().getCount(); i++) { views.add(new ViewData(getChildAt(i), new TranslateAnimation(0, 0, 0, 0))); } posY = 0; movY = 0; touchY = event.getY(); View temp = getChildAt(0); temp.measure(0, 0); viewHeight = temp.getMeasuredHeight(); viewIndex = (int) (event.getY() / temp.getMeasuredHeight()) + fixedPositionOffset; indexToReorder = viewIndex; if (viewIndex < 0 || viewIndex > views.size() - 1) { mDetector.onTouchEvent(event); return true; } view = getChildAt(viewIndex); // - firstVisibleItem if (event.getX() < Util.dp2px(5) || event.getX() > Util.dp2px(85)) { // draging is enabled only when touching the left part of the view isDragStarted = false; } else { isDragStarted = true; } } if (view == null) { view = getChildAt(0); viewIndex = 0; } if (isDragStarted) { switch (event.getAction()) { case MotionEvent.ACTION_CANCEL: case MotionEvent.ACTION_UP: adapter.notifyDataSetChanged(); view.clearAnimation(); translate(view, 0, true); isDragStarted = false; if (adapter.getCount() > 1) adapter.reorder(0, 0, true); Iterator<ViewData> it = views.iterator(); while (it.hasNext()) { it.next().animation.cancel(); } if (animation != null) animation.cancel(); break; case MotionEvent.ACTION_DOWN: moveCount = 0; touchY = event.getY(); break; case MotionEvent.ACTION_MOVE: float newTouchY = event.getY(); float delta = newTouchY - touchY; indexToAnimate = (int) (event.getY() / viewHeight) + fixedPositionOffset; try { if (indexToReorder != indexToAnimate) { if (indexToAnimate >= 0 && indexToAnimate < adapter.getCount()) { int newY = delta > 0 ? views.get(indexToAnimate).lastY - viewHeight : views.get(indexToAnimate).lastY + viewHeight; ViewData animateView = views.get(indexToAnimate); if (animateView.animation != null && animateView.animation.isInitialized()) animateView.animation.cancel(); animateView.animation = new TranslateAnimation(0, 0, animateView.lastY, newY); animateView.lastY = newY; animateView.animation.setFillAfter(true); animateView.animation.setFillBefore(true); animateView.animation.setDuration(500); adapter.reorder(indexToAnimate + firstVisibleItem, indexToReorder + firstVisibleItem, false); animateView.view.clearAnimation(); animateView.view.startAnimation(animateView.animation); ViewData temp = animateView; views.set(indexToAnimate, views.get(indexToReorder)); views.set(indexToReorder, temp); indexToReorder = indexToAnimate; } } } catch (Exception e) { e.getLocalizedMessage(); } translate(view, delta, false); touchY = newTouchY; break; } } else if (event.getAction() == MotionEvent.ACTION_MOVE) { final float newY = event.getY(); if ((movY == 0 && Math.abs(newY - touchY) > viewHeight) || Math.abs(newY - movY) > viewHeight) { movY = newY; } } return true; } TranslateAnimation animation; float posY = 0, movY = 0; float touchY = 0; int maxSlide = 200; boolean slidden = false; int moveCount = 0; void translate(View v, float deltaY, final boolean finalAnim) { float newY = posY + deltaY; if (animation != null && animation.isInitialized()) animation.cancel(); animation = new TranslateAnimation(0, 0, posY, newY); animation.setDuration(finalAnim ? 0 : 100); animation.setAnimationListener(new AnimationListener() { @Override public void onAnimationStart(Animation animation) { } @Override public void onAnimationRepeat(Animation animation) { } @Override public void onAnimationEnd(Animation animation) { if (!finalAnim) { animation.setFillEnabled(true); animation.setFillAfter(true); } else { view.clearAnimation(); posY = 0; } } }); posY = newY; v.startAnimation(animation); } public void clearAnimations() { if (view != null) view.clearAnimation(); for (int i = 0; i < getChildCount(); i++) { getChildAt(i).clearAnimation(); } invalidate(); } private static class ViewData { public View view; public TranslateAnimation animation; public int lastY = 0; public ViewData(View view, TranslateAnimation animation) { this.view = view; this.animation = animation; } } float lastDistanceY = 0; class MyGestureListener extends GestureDetector.SimpleOnGestureListener { @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { if (adapter != null && adapter.getCount() > 1) { if (Math.signum(distanceY) != Math.signum(lastDistanceY)) { lastDistanceY = 0; } lastDistanceY += distanceY; LOG.d("scroll diff = " + distanceY); if (Math.abs(lastDistanceY) > viewHeight) { int itemsToScroll = (int) (viewHeight / Math.abs(lastDistanceY)); if (itemsToScroll == 0) { itemsToScroll = 1; } if (firstVisibleItem != 0 && distanceY < 0) { smoothScrollToPosition(firstVisibleItem - itemsToScroll); firstVisibleItem -= itemsToScroll; } else if (firstVisibleItem != adapter.getCount() - 1 && distanceY > 0) { smoothScrollToPosition(firstVisibleItem + getChildCount() + itemsToScroll - 1); firstVisibleItem += itemsToScroll; } if (firstVisibleItem < 0) { firstVisibleItem = 0; } if (firstVisibleItem > adapter.getCount() - getChildCount()) { firstVisibleItem = adapter.getCount() - getChildCount(); } lastDistanceY = 0; } } return true; }; @Override public boolean onDown(MotionEvent event) { return true; } @Override public boolean onFling(MotionEvent event1, MotionEvent event2, float velocityX, float velocityY) { LOG.d("fling"); if (adapter != null && adapter.getCount() > 1) { int itemsToScroll = (int) (viewHeight / Math.abs(velocityY)); if (firstVisibleItem != 0 && velocityY > 0) { smoothScrollToPosition(firstVisibleItem - itemsToScroll); firstVisibleItem -= itemsToScroll; } else if (firstVisibleItem != adapter.getCount() - 1 && velocityY < 0) { smoothScrollToPosition(firstVisibleItem + getChildCount() + itemsToScroll - 1); firstVisibleItem += itemsToScroll; } if (firstVisibleItem < 0) { firstVisibleItem = 0; } if (firstVisibleItem > adapter.getCount() - getChildCount()) { firstVisibleItem = adapter.getCount() - getChildCount(); } } return true; } } }