使用RecylerView完成拖动排序高仿qq侧滑删除功能

MyItemTouchHelperCallback callback = new MyItemTouchHelperCallback(adapter); //此类继承ItemTouchHelper.Callback,这是帮助处理RecylerView拖动侧滑操作的辅助类 
ItemTouchHelper helper = new ItemTouchHelper(callback); //用上面实例化的callback实例化一个ItemTouchHelper对象。套路代码，没啥好说的，固定做法 
helper.attachToRecyclerView(recyclerView); //让help帮助处理recylerview的滑动，侧滑操作

public interface OnMoveAndSwipeListener { 
public boolean onItemMove(int fromPosition, int toPosition); //注意返回boolean哦 
public void onItemDismiss(int position); 
}

@Override 
public boolean onItemMove(int fromPosition, int toPosition) { 
if (fromPosition < toPosition) { 
//往下移动时,做数据交换 
for (int i = fromPosition; i < toPosition; i++) { 
Collections.swap(list,i,i+1); 
} 
}else{ 
//往上移动,做数据交换 
for (int i = fromPosition; i >toPosition ; i--) { 
Collections.swap(list,i,i-1); 
} 
} 
notifyItemMoved(fromPosition,toPosition); 
return true; 
} 
@Override 
public void onItemDismiss(int position) { 
//此例没有对侧滑做操作，如果需要就在此模仿onItemMove方法，删除对应位置的数据，并且刷新界面就可以了 
}

public class MyItemTouchHelperCallback extends ItemTouchHelper.Callback { 
MyAdapter adapter; 
public MyItemTouchHelperCallback(MyAdapter adapter) { 
this.adapter = adapter; 
} 
@Override 
public int getMovementFlags(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) { 
//复写此方法用来设置我需要处理哪些操作 
//我要处理上下拖动，就设置up down，如果是gridview类型的recylerview，up,down,left,right都可以处理 
final int moveMode = ItemTouchHelper.UP | ItemTouchHelper.DOWN; 
//本例没有处理侧滑，如果需要处理侧滑，就把注释取消掉 
//final int swipeMode = ItemTouchHelper.START | ItemTouchHelper.END; 
Log.e("getMovementFlags","getMovementFlags"); 
return makeMovementFlags(moveMode, 0);//不处理什么，就传0 
} 
@Override 
public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) { 
//当你拖动时就会触发此回调，然后调用在adapter中复写的onItemMove方法，去交换数据 
return adapter.onItemMove(viewHolder.getAdapterPosition(),target.getAdapterPosition()); 
} 
@Override 
public void onSwiped(RecyclerView.ViewHolder viewHolder, int direction) { 
//如果你要处理侧滑就取消注释，逻辑和上面的onMove一样 
// adapter.onItemDismiss(viewHolder.getAdapterPosition()); 
} 
@Override 
public void onSelectedChanged(RecyclerView.ViewHolder viewHolder, int actionState) { 
//此方法在你选中一个item拖动时触发，所以你可以在这里给选中的item设置一个背景色，用于高亮提示你选中了这个背景色 
super.onSelectedChanged(viewHolder, actionState); 
if (actionState!= ItemTouchHelper.ACTION_STATE_IDLE){ 
viewHolder.itemView.setBackgroundColor(Color.LTGRAY); 
} 
} 
@Override 
public void clearView(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) { 
//因为你设置了背景色，所以在你不选中的时候，要取消掉这个背景色。 
super.clearView(recyclerView, viewHolder); 
viewHolder.itemView.setBackgroundColor(0); 
} 
}

<?xml version="1.0" encoding="utf-8"?> 
<!--背景view，用于提示用户操作结果--> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:tools="http://schemas.android.com/tools" 
android:id="@+id/rl_background" 
android:layout_width="match_parent" 
android:layout_height="wrap_content"> 
<ImageView 
android:id="@+id/iv_done" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content" 
android:layout_centerVertical="true" 
android:layout_marginLeft="16dp" 
android:layout_marginStart="16dp" 
android:src="@mipmap/bt_ic_done_white_24" /> 
<ImageView 
android:id="@+id/iv_schedule" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content" 
android:layout_alignParentRight="true" 
android:layout_centerVertical="true" 
android:layout_marginEnd="16dp" 
android:layout_marginRight="16dp" 
android:src="@mipmap/bt_ic_schedule_white_24" /> 
<!--滑动操作的view--> 
<LinearLayout 
android:id="@+id/ll_item" 
android:layout_width="match_parent" 
android:layout_height="64dp" 
android:background="@android:color/white" 
android:gravity="center_vertical" 
android:orientation="vertical" 
android:paddingLeft="16dp" 
android:paddingRight="16dp"> 
<TextView 
android:id="@+id/tv_item" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content" 
android:textAppearance="?android:attr/textAppearanceMedium" 
tools:text="Item" /> 
</LinearLayout> 
<View 
android:layout_width="match_parent" 
android:layout_height="1dp" 
android:layout_below="@id/ll_item" 
android:background="#B2B2b2" /> 
</RelativeLayout>

<span style="white-space:pre"> </span> @Override 
public void clearView(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) { 
// 释放View时回调，清除背景颜色，隐藏图标 
// 默认是操作ViewHolder的itemView，这里调用ItemTouchUIUtil的clearView方法传入指定的view 
getDefaultUIUtil().clearView(((SampleAdapter.ItemViewHolder) viewHolder).vItem); 
((SampleAdapter.ItemViewHolder) viewHolder).vBackground.setBackgroundColor(Color.TRANSPARENT); 
((SampleAdapter.ItemViewHolder) viewHolder).ivSchedule.setVisibility(View.GONE); 
((SampleAdapter.ItemViewHolder) viewHolder).ivDone.setVisibility(View.GONE); 
} 
@Override 
public void onSelectedChanged(RecyclerView.ViewHolder viewHolder, int actionState) { 
// 当viewHolder的滑动或拖拽状态改变时回调 
if (viewHolder != null) { 
// 默认是操作ViewHolder的itemView，这里调用ItemTouchUIUtil的clearView方法传入指定的view 
getDefaultUIUtil().onSelected(((SampleAdapter.ItemViewHolder) viewHolder).vItem); 
} 
} 
@Override 
public void onChildDraw(Canvas c, RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState, boolean isCurrentlyActive) { 
// ItemTouchHelper的onDraw方法会调用该方法，可以使用Canvas对象进行绘制，绘制的图案会在RecyclerView的下方 
// 默认是操作ViewHolder的itemView，这里调用ItemTouchUIUtil的clearView方法传入指定的view 
getDefaultUIUtil().onDraw(c, recyclerView, ((SampleAdapter.ItemViewHolder) viewHolder).vItem, dX, dY, actionState, isCurrentlyActive); 
if (dX > 0) { // 向左滑动是的提示 
((SampleAdapter.ItemViewHolder) viewHolder).vBackground.setBackgroundResource(R.color.colorDone); 
((SampleAdapter.ItemViewHolder) viewHolder).ivDone.setVisibility(View.VISIBLE); 
((SampleAdapter.ItemViewHolder) viewHolder).ivSchedule.setVisibility(View.GONE); 
} 
if (dX < 0) { // 向右滑动时的提示 
((SampleAdapter.ItemViewHolder) viewHolder).vBackground.setBackgroundResource(R.color.colorSchedule); 
((SampleAdapter.ItemViewHolder) viewHolder).ivSchedule.setVisibility(View.VISIBLE); 
((SampleAdapter.ItemViewHolder) viewHolder).ivDone.setVisibility(View.GONE); 
} 
} 
@Override 
public void onChildDrawOver(Canvas c, RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, float dX, float dY, int actionState, boolean isCurrentlyActive) { 
// ItemTouchHelper的onDrawOver方法会调用该方法，可以使用Canvas对象进行绘制，绘制的图案会在RecyclerView的上方 
// 默认是操作ViewHolder的itemView，这里调用ItemTouchUIUtil的clearView方法传入指定的view 
getDefaultUIUtil().onDrawOver(c, recyclerView, ((SampleAdapter.ItemViewHolder) viewHolder).vItem, dX, dY, actionState, isCurrentlyActive); 
} 
});