RecyclerViewItemTouchHelperDemo【使用ItemTouchHelper进行拖拽排序功能】
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前言
记录使用ItemTouchHelper对Recyclerview进行拖拽排序功能的实现。
效果图
代码分析
ItemTouchHelper是一个工具类，可实现侧滑删除和拖拽移动，使用这个工具类需要RecyclerView和Callback。同时根据需要重写onMove和onSwiped方法。
使用步骤
一、项目组织结构图
注意事项：
1、 导入类文件后需要change包名以及重新import R文件路径
2、 Values目录下的文件（strings.xml、dimens.xml、colors.xml等），如果项目中存在，则复制里面的内容，不要整个覆盖
二、导入步骤
（1）在build.gradle中引用recyclerview【版本号和appcompat保持一致】
apply plugin: 'com.android.application'
android {
compileSdkVersion 27
defaultConfig {
applicationId "com.why.project.recyclerviewitemtouchhelperdemo"
minSdkVersion 16
targetSdkVersion 27
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation 'com.android.support:appcompat-v7:27.1.1'
implementation 'com.android.support.constraint:constraint-layout:1.1.2'
testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'
//RecyclerView
compile "com.android.support:recyclerview-v7:27.1.1"
}
（2）在AndroidManifest.xml中声明震动权限
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.why.project.recyclerviewitemtouchhelperdemo"> <!-- ======================RecyclerView拖拽震动效果====================== --> <uses-permission android:name="android.permission.VIBRATE" /> <application android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round" android:supportsRtl="true" android:theme="@style/AppTheme"> <activity android:name=".MainActivity"> <intent-filter> <action android:name="android.intent.action.MAIN"/> <category android:name="android.intent.category.LAUNCHER"/> </intent-filter> </activity> </application> </manifest>
（3）在项目中实现Recyclerview基本数据展现
1、创建Bean类
package com.why.project.recyclerviewitemtouchhelperdemo.bean; /** * Created by HaiyuKing * Used 列表项的bean类 */ public class ChannelBean { private String channelId;//频道id值 private String channelName;//频道名称 public String getChannelId() { return channelId; } public void setChannelId(String channelId) { this.channelId = channelId; } public String getChannelName() { return channelName; } public void setChannelName(String channelName) { this.channelName = channelName; } }
2、创建Adapter以及item的布局文件
package com.why.project.recyclerviewitemtouchhelperdemo.adapter; import android.content.Context; import android.support.v7.widget.RecyclerView; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.LinearLayout; import android.widget.TextView; import com.why.project.recyclerviewitemtouchhelperdemo.R; import com.why.project.recyclerviewitemtouchhelperdemo.bean.ChannelBean; import java.util.ArrayList; /** * Created by HaiyuKing * Used 频道列表适配器 */ public class ChannelAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{ /**上下文*/ private Context myContext; /**频道集合*/ private ArrayList<ChannelBean> listitemList; /** * 构造函数 */ public ChannelAdapter(Context context, ArrayList<ChannelBean> itemlist) { myContext = context; listitemList = itemlist; } /** * 获取总的条目数 */ @Override public int getItemCount() { return listitemList.size(); } /** * 创建ViewHolder */ @Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { View view = LayoutInflater.from(myContext).inflate(R.layout.channel_list_item, parent, false); ItemViewHolder itemViewHolder = new ItemViewHolder(view); return itemViewHolder; } /** * 声明grid列表项ViewHolder*/ static class ItemViewHolder extends RecyclerView.ViewHolder { public ItemViewHolder(View view) { super(view); listItemLayout = (LinearLayout) view.findViewById(R.id.listitem_layout); mChannelName = (TextView) view.findViewById(R.id.tv_channelName); } LinearLayout listItemLayout; TextView mChannelName; } /** * 将数据绑定至ViewHolder */ @Override public void onBindViewHolder(RecyclerView.ViewHolder viewHolder, int index) { //判断属于列表项还是上拉加载区域 if(viewHolder instanceof ItemViewHolder){ ChannelBean channelBean = listitemList.get(index); final ItemViewHolder itemViewHold = ((ItemViewHolder)viewHolder); itemViewHold.mChannelName.setText(channelBean.getChannelName()); //如果设置了回调，则设置点击事件 if (mOnItemClickLitener != null) { itemViewHold.listItemLayout.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { int position = itemViewHold.getLayoutPosition();//在增加数据或者减少数据时候，position和index就不一样了 mOnItemClickLitener.onItemClick(itemViewHold.listItemLayout, position); } }); //长按事件 itemViewHold.listItemLayout.setOnLongClickListener(new View.OnLongClickListener() { @Override public boolean onLongClick(View view) { int position = itemViewHold.getLayoutPosition();//在增加数据或者减少数据时候，position和index就不一样了 mOnItemClickLitener.onItemLongClick(itemViewHold.listItemLayout, position); return false; } }); } } } /** * 添加Item--用于动画的展现*/ public void addItem(int position,ChannelBean listitemBean) { listitemList.add(position,listitemBean); notifyItemInserted(position); } /** * 删除Item--用于动画的展现*/ public void removeItem(int position) { listitemList.remove(position); notifyItemRemoved(position); } /*=====================添加OnItemClickListener回调================================*/ public interface OnItemClickLitener { void onItemClick(View view, int position); void onItemLongClick(View view, int position); } private OnItemClickLitener mOnItemClickLitener; public void setOnItemClickLitener(OnItemClickLitener mOnItemClickLitener) { this.mOnItemClickLitener = mOnItemClickLitener; } }
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/listitem_layout" android:layout_width="match_parent" android:layout_height="wrap_content" android:orientation="vertical" android:padding="10dp" android:layout_margin="10dp" android:background="#c5c5c5"> <TextView android:id="@+id/tv_channelName" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="频道名称" android:textSize="18sp" android:layout_gravity="center"/> </LinearLayout>
3、在Activity布局文件中引用Recyclerview控件
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <android.support.v7.widget.RecyclerView android:id="@+id/recycler_view" android:layout_width="match_parent" android:layout_height="match_parent" android:cacheColorHint="#00000000" android:divider="@null" android:listSelector="#00000000" android:scrollbars="none" /> </RelativeLayout>
4、在Activity类中初始化recyclerview数据
package com.why.project.recyclerviewitemtouchhelperdemo; import android.app.Service; import android.graphics.Color; import android.os.Bundle; import android.os.Vibrator; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.GridLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.helper.ItemTouchHelper; import android.util.Log; import android.view.View; import android.widget.Toast; import com.why.project.recyclerviewitemtouchhelperdemo.adapter.ChannelAdapter; import com.why.project.recyclerviewitemtouchhelperdemo.bean.ChannelBean; import java.util.ArrayList; import java.util.Collections; public class MainActivity extends AppCompatActivity { private RecyclerView mRecyclerView; private ArrayList<ChannelBean> mChannelBeanArrayList; private ChannelAdapter mChannelAdapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initViews(); initDatas(); initEvents(); } private void initViews() { mRecyclerView = findViewById(R.id.recycler_view); } private void initDatas() { //初始化集合 mChannelBeanArrayList = new ArrayList<ChannelBean>(); for(int i=0; i<10;i++){ ChannelBean channelBean = new ChannelBean(); channelBean.setChannelId("123"+i); channelBean.setChannelName("频道"+i); mChannelBeanArrayList.add(channelBean); } //设置布局管理器 GridLayoutManager gridLayoutManager = new GridLayoutManager(this,3); mRecyclerView.setLayoutManager(gridLayoutManager); //设置适配器 if(mChannelAdapter == null){ //设置适配器 mChannelAdapter = new ChannelAdapter(this, mChannelBeanArrayList); mRecyclerView.setAdapter(mChannelAdapter); //添加分割线 //设置添加删除动画 //调用ListView的setSelected(!ListView.isSelected())方法，这样就能及时刷新布局 mRecyclerView.setSelected(true); }else{ mChannelAdapter.notifyDataSetChanged(); } }
private void initEvents() { //列表适配器的点击监听事件 mChannelAdapter.setOnItemClickLitener(new ChannelAdapter.OnItemClickLitener() { @Override public void onItemClick(View view, int position) { Toast.makeText(MainActivity.this, mChannelBeanArrayList.get(position).getChannelName(), Toast.LENGTH_SHORT).show(); } @Override public void onItemLongClick(View view, int position) { Toast.makeText(MainActivity.this, "长按", Toast.LENGTH_SHORT).show(); } }); } }
三、使用方法
在基本的Recyclerview基础上添加ItemTouchHelper【注意，紫色标记的是用来演示用的，可以去掉】
package com.why.project.recyclerviewitemtouchhelperdemo; import android.app.Service; import android.graphics.Color; import android.os.Bundle; import android.os.Vibrator; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.GridLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.helper.ItemTouchHelper; import android.util.Log; import android.view.View; import android.widget.Toast; import com.why.project.recyclerviewitemtouchhelperdemo.adapter.ChannelAdapter; import com.why.project.recyclerviewitemtouchhelperdemo.bean.ChannelBean; import java.util.ArrayList; import java.util.Collections; public class MainActivity extends AppCompatActivity { private RecyclerView mRecyclerView; private ArrayList<ChannelBean> mChannelBeanArrayList; private ChannelAdapter mChannelAdapter; /**拖拽功能*/ private ItemTouchHelper itemTouchHelper; private int currentPagePosition = -1;//当前拖拽的item的原始位置，从0开始【长按时赋值】，用来和currentPageNewPosition对比进行判断是否执行排序接口 private int currentPageNewPosition = -1;//当前item拖拽后的位置，从0开始 private boolean newOrder = false;//标记是否拖拽排序过，默认是false @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initViews(); initDatas(); initEvents(); } private void initViews() { mRecyclerView = findViewById(R.id.recycler_view); } private void initDatas() { //初始化集合 mChannelBeanArrayList = new ArrayList<ChannelBean>(); for(int i=0; i<10;i++){ ChannelBean channelBean = new ChannelBean(); channelBean.setChannelId("123"+i); channelBean.setChannelName("频道"+i); mChannelBeanArrayList.add(channelBean); } //设置布局管理器 GridLayoutManager gridLayoutManager = new GridLayoutManager(this,3); mRecyclerView.setLayoutManager(gridLayoutManager); //设置适配器 if(mChannelAdapter == null){ //设置适配器 mChannelAdapter = new ChannelAdapter(this, mChannelBeanArrayList); mRecyclerView.setAdapter(mChannelAdapter); //添加分割线 //设置添加删除动画 //调用ListView的setSelected(!ListView.isSelected())方法，这样就能及时刷新布局 mRecyclerView.setSelected(true); }else{ mChannelAdapter.notifyDataSetChanged(); } initItemTouchHelper(); } private void initItemTouchHelper() { //拖拽 itemTouchHelper = new ItemTouchHelper(new ItemTouchHelper.Callback(){ //开启长按拖拽功能，默认为true【暂时用不到】 //如果需要我们自定义拖拽和滑动，可以设置为false，然后调用itemTouchHelper.startDrag(ViewHolder)方法来开启！ @Override public boolean isLongPressDragEnabled() { return true; } //开始滑动功能，默认为true【暂时用不到】 //如果需要我们自定义拖拽和滑动，可以设置为false，然后调用itemTouchHelper.startSwipe(ViewHolder)方法来开启！ @Override public boolean isItemViewSwipeEnabled() { return true; } /*用于设置是否处理拖拽事件和滑动事件，以及拖拽和滑动操作的方向 比如如果是列表类型的RecyclerView，拖拽只有UP、DOWN两个方向 而如果是网格类型的则有UP、DOWN、LEFT、RIGHT四个方向 */ @Override public int getMovementFlags(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) { int dragFlags = 0;//dragFlags 是拖拽标志 int swipeFlags = 0;//swipeFlags是侧滑标志，我们把swipeFlags 都设置为0，表示不处理滑动操作 if (recyclerView.getLayoutManager() instanceof GridLayoutManager) { dragFlags = ItemTouchHelper.UP | ItemTouchHelper.DOWN | ItemTouchHelper.LEFT | ItemTouchHelper.RIGHT; swipeFlags = 0; } else { dragFlags = ItemTouchHelper.UP | ItemTouchHelper.DOWN; swipeFlags = 0; } Log.w("ItemTouchHelper","{getMovementFlags}dragFlags="+dragFlags+";swipeFlags="+swipeFlags); return makeMovementFlags(dragFlags, swipeFlags); } /*如果我们设置了非0的dragFlags ，那么当我们长按item的时候就会进入拖拽并在拖拽过程中不断回调onMove()方法 我们就在这个方法里获取当前拖拽的item和已经被拖拽到所处位置的item的ViewHolder， 有了这2个ViewHolder，我们就可以交换他们的数据集并调用Adapter的notifyItemMoved方法来刷新item*/ @Override public boolean onMove(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder, RecyclerView.ViewHolder target) { int fromPosition = viewHolder.getAdapterPosition();//得到拖动ViewHolder的position int toPosition = target.getAdapterPosition();//得到目标ViewHolder的position Log.w("ItemTouchHelper","{onMove}fromPosition="+fromPosition+";toPosition="+toPosition); //这里可以添加判断，实现某一项不可交换 if (fromPosition < toPosition) { for (int i = fromPosition; i < toPosition; i++) { Collections.swap(mChannelBeanArrayList, i, i + 1); } } else { for (int i = fromPosition; i > toPosition; i--) { Collections.swap(mChannelBeanArrayList, i, i - 1); } } mChannelAdapter.notifyItemMoved(fromPosition, toPosition); return true; } /*同理如果我们设置了非0的swipeFlags，我们在侧滑item的时候就会回调onSwiped的方法，我们不处理这个事件，空着就行了。*/ @Override public void onSwiped(RecyclerView.ViewHolder viewHolder, int direction) { } //我们希望拖拽的Item在拖拽的过程中发生震动或者颜色变深，这样就需要继续重写下面两个方法 //当长按选中item的时候（拖拽开始的时候）调用 //ACTION_STATE_IDLE：闲置状态 //ACTION_STATE_SWIPE：滑动状态 //ACTION_STATE_DRAG：拖拽状态 @Override public void onSelectedChanged(RecyclerView.ViewHolder viewHolder, int actionState) { Log.w("ItemTouchHelper","{onSelectedChanged}actionState="+actionState); if (actionState == ItemTouchHelper.ACTION_STATE_DRAG) { //获取系统震动服务 Vibrator vib = (Vibrator) MainActivity.this.getSystemService(Service.VIBRATOR_SERVICE); //震动70毫秒 vib.vibrate(70); viewHolder.itemView.setPressed(true); viewHolder.itemView.setBackgroundColor(Color.parseColor("#ff0000"));//演示拖拽的时候item背景颜色加深（实际情况中去掉） } super.onSelectedChanged(viewHolder, actionState); } //当手指松开的时候（拖拽或滑动完成的时候）调用，这时候我们可以将item恢复为原来的状态（相对于背景颜色加深来说的） @Override public void clearView(RecyclerView recyclerView, RecyclerView.ViewHolder viewHolder) { super.clearView(recyclerView, viewHolder); Log.w("ItemTouchHelper","{clearView}viewHolder.getAdapterPosition="+viewHolder.getAdapterPosition()); viewHolder.itemView.setPressed(false); currentPageNewPosition = viewHolder.getAdapterPosition(); Log.w("ItemTouchHelper","{clearView}currentPagePosition="+currentPagePosition); Log.w("ItemTouchHelper","{clearView}currentPageNewPosition="+currentPageNewPosition); if(!(currentPagePosition == currentPageNewPosition)){ newOrder = true; //执行其他方法，比如设置拖拽后的item为选中状态 } viewHolder.itemView.setBackgroundColor(Color.parseColor("#c5c5c5"));//演示拖拽的完毕后item背景颜色恢复原样（实际情况中去掉） mChannelAdapter.notifyDataSetChanged();//解决重叠问题 } }); //设置是否可以排序 itemTouchHelper.attachToRecyclerView(mRecyclerView); } private void initEvents() { //列表适配器的点击监听事件 mChannelAdapter.setOnItemClickLitener(new ChannelAdapter.OnItemClickLitener() { @Override public void onItemClick(View view, int position) { Toast.makeText(MainActivity.this, mChannelBeanArrayList.get(position).getChannelName(), Toast.LENGTH_SHORT).show(); } @Override public void onItemLongClick(View view, int position) { currentPagePosition = position;//拖拽用到的 Toast.makeText(MainActivity.this, "长按", Toast.LENGTH_SHORT).show(); } }); } }
混淆配置
无
参考资料
Android使用ItemTouchHelper打造可拖拽的RecyclerView
RecyclerView进阶：使用ItemTouchHelper实现拖拽和侧滑删除
RecyclerView爱恨情仇之ItemTouchHelper
项目demo下载地址
https://github.com/haiyuKing/RecyclerViewItemTouchHelperDemo
