版權聲明:本文為HaiyuKing原創文章,轉載請注明出處!
前言
FlexboxLayout是一個Google 開源的庫項目,它將CSS Flexible Box Layout Module的類似功能 引入Android。
這里只記錄FlexboxLayoutManager搭配RecyclerView實現流式布局的實現方式,至於FlexboxLayout的獨立使用以及相關資料,請閱讀《參考資料》。
效果圖
代碼分析
將FlexboxLayoutManager理解為RecyclerView的一種manager,比如LinearLayoutManager等。
//設置布局管理器 FlexboxLayoutManager flexboxLayoutManager = new FlexboxLayoutManager(MainActivity.this); //flexDirection 屬性決定主軸的方向(即項目的排列方向)。類似 LinearLayout 的 vertical 和 horizontal。 flexboxLayoutManager.setFlexDirection(FlexDirection.ROW);//主軸為水平方向,起點在左端。 //flexWrap 默認情況下 Flex 跟 LinearLayout 一樣,都是不帶換行排列的,但是flexWrap屬性可以支持換行排列。 flexboxLayoutManager.setFlexWrap(FlexWrap.WRAP);//按正常方向換行 //justifyContent 屬性定義了項目在主軸上的對齊方式。 flexboxLayoutManager.setJustifyContent(JustifyContent.FLEX_START);//交叉軸的起點對齊。 mRecyclerView.setLayoutManager(flexboxLayoutManager);
使用步驟
一、項目組織結構圖
注意事項:
1、 導入類文件后需要change包名以及重新import R文件路徑
2、 Values目錄下的文件(strings.xml、dimens.xml、colors.xml等),如果項目中存在,則復制里面的內容,不要整個覆蓋
二、導入步驟
(1)在build.gradle中引用recyclerview【版本號和appcompat保持一致】和Flexboxlayout
apply plugin: 'com.android.application'
android {
compileSdkVersion 27
defaultConfig {
applicationId "com.why.project.recyclerflexboxlayoutmanagerdemo"
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" //FlexboxLayout implementation 'com.google.android:flexbox:1.0.0'
}
(2)在項目中實現Recyclerview基本數據展現
1、創建Bean類

package com.why.project.recyclerflexboxlayoutmanagerdemo.bean; import java.util.Date; /** * Created by HaiyuKing * Used 搜索歷史記錄bean */ public class SearchHistoryBean { private String searchTitle;//搜索的標題 private Date searchDate;//搜索的時間(如果重新搜索了的話,只需要更新搜索時間即可,不需要添加) public String getSearchTitle() { return searchTitle; } public void setSearchTitle(String searchTitle) { this.searchTitle = searchTitle; } public Date getSearchDate() { return searchDate; } public void setSearchDate(Date searchDate) { this.searchDate = searchDate; } }
2、創建Adapter以及item的布局文件

package com.why.project.recyclerflexboxlayoutmanagerdemo.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.recyclerflexboxlayoutmanagerdemo.R; import com.why.project.recyclerflexboxlayoutmanagerdemo.bean.SearchHistoryBean; import java.util.ArrayList; /** * Created by HaiyuKing * Used 搜索記錄列表適配器 */ public class SearchHistoryAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{ /**上下文*/ private Context myContext; /**頻道集合*/ private ArrayList<SearchHistoryBean> listitemList; /** * 構造函數 */ public SearchHistoryAdapter(Context context, ArrayList<SearchHistoryBean> itemlist) { myContext = context; listitemList = itemlist; } /** * 獲取總的條目數 */ @Override public int getItemCount() { return listitemList.size(); } /** * 創建ViewHolder */ @Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { View view = LayoutInflater.from(myContext).inflate(R.layout.searchhistory_list_item, parent, false); ItemViewHolder itemViewHolder = new ItemViewHolder(view); return itemViewHolder; } /** * 聲明grid列表項ViewHolder*/ static class ItemViewHolder extends RecyclerView.ViewHolder { public ItemViewHolder(View view) { super(view); listItemLayout = (LinearLayout) view.findViewById(R.id.listitem_layout); mTitle = (TextView) view.findViewById(R.id.tv_title); } LinearLayout listItemLayout; TextView mTitle; } /** * 將數據綁定至ViewHolder */ @Override public void onBindViewHolder(RecyclerView.ViewHolder viewHolder, int index) { //判斷屬於列表項還是上拉加載區域 if(viewHolder instanceof ItemViewHolder){ SearchHistoryBean searchHistoryBean = listitemList.get(index); final ItemViewHolder itemViewHold = ((ItemViewHolder)viewHolder); itemViewHold.mTitle.setText(searchHistoryBean.getSearchTitle()); //如果設置了回調,則設置點擊事件 if (mOnItemClickLitener != null) { itemViewHold.listItemLayout.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { int position = itemViewHold.getLayoutPosition();//在增加數據或者減少數據時候,position和index就不一樣了 mOnItemClickLitener.onItemClick(itemViewHold.listItemLayout, position); } }); } } } /** * 添加Item--用於動畫的展現*/ public void addItem(int position,SearchHistoryBean listitemBean) { listitemList.add(position,listitemBean); notifyItemInserted(position); } /** * 刪除Item--用於動畫的展現*/ public void removeItem(int position) { listitemList.remove(position); notifyItemRemoved(position); } /*=====================添加OnItemClickListener回調================================*/ public interface OnItemClickLitener { void onItemClick(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="wrap_content" android:layout_height="wrap_content" android:orientation="vertical" android:padding="5dp" android:layout_marginTop="8dp" android:layout_marginLeft="8dp" android:layout_marginRight="8dp" android:background="@drawable/searchhistory_item_bg"> <TextView android:id="@+id/tv_title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="標題" android:textSize="14sp" android:textColor="#333333" android:layout_gravity="center"/> </LinearLayout>
列表項布局文件中用到了背景drawable文件

<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle"> <!-- 填充--> <solid android:color="#00000000"/> <!-- 描邊 --> <stroke android:width="1dp" android:color="#7F7F7F" /> <!-- 圓角 --> <corners android:radius="2dp" /> </shape>
3、在Activity布局文件中引用Recyclerview控件
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" android:background="#ffffff"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="歷史記錄"/> <!-- RecyclerView列表 --> <android.support.v7.widget.RecyclerView android:id="@+id/recycler_view" android:layout_width="match_parent" android:layout_height="wrap_content" android:cacheColorHint="#00000000" android:divider="@null" android:listSelector="#00000000" android:scrollbars="none" /> </LinearLayout>
三、使用方法
(1)Activity中使用如下
package com.why.project.recyclerflexboxlayoutmanagerdemo; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.RecyclerView; import android.view.View; import android.widget.Toast; import com.google.android.flexbox.FlexDirection; import com.google.android.flexbox.FlexWrap; import com.google.android.flexbox.FlexboxLayoutManager; import com.google.android.flexbox.JustifyContent; import com.why.project.recyclerflexboxlayoutmanagerdemo.adapter.SearchHistoryAdapter; import com.why.project.recyclerflexboxlayoutmanagerdemo.bean.SearchHistoryBean; import java.util.ArrayList; import java.util.Calendar; public class MainActivity extends AppCompatActivity { private RecyclerView mRecyclerView; private ArrayList<SearchHistoryBean> mSearchHistoryBeanArrayList; private SearchHistoryAdapter mSearchHistoryAdapter; @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 mSearchHistoryBeanArrayList = new ArrayList<SearchHistoryBean>(); String[] testDatas = new String[]{"牙刷","滅蚊器","移動空調","吸塵器","布衣櫃","收納箱 書箱","暑期美食滿99減15","掛燙機","吸水拖把","反季特惠"}; for(int i=0; i<testDatas.length;i++){ SearchHistoryBean channelBean = new SearchHistoryBean(); channelBean.setSearchTitle(testDatas[i]); //獲取當前日期 Calendar calendar = Calendar.getInstance(); channelBean.setSearchDate(calendar.getTime()); mSearchHistoryBeanArrayList.add(channelBean); } //設置布局管理器 FlexboxLayoutManager flexboxLayoutManager = new FlexboxLayoutManager(MainActivity.this); //flexDirection 屬性決定主軸的方向(即項目的排列方向)。類似 LinearLayout 的 vertical 和 horizontal。 flexboxLayoutManager.setFlexDirection(FlexDirection.ROW);//主軸為水平方向,起點在左端。 //flexWrap 默認情況下 Flex 跟 LinearLayout 一樣,都是不帶換行排列的,但是flexWrap屬性可以支持換行排列。 flexboxLayoutManager.setFlexWrap(FlexWrap.WRAP);//按正常方向換行 //justifyContent 屬性定義了項目在主軸上的對齊方式。 flexboxLayoutManager.setJustifyContent(JustifyContent.FLEX_START);//交叉軸的起點對齊。 mRecyclerView.setLayoutManager(flexboxLayoutManager); //設置適配器 if(mSearchHistoryAdapter == null){ //設置適配器 mSearchHistoryAdapter = new SearchHistoryAdapter(this, mSearchHistoryBeanArrayList); mRecyclerView.setAdapter(mSearchHistoryAdapter); //添加分割線 //設置添加刪除動畫 //調用ListView的setSelected(!ListView.isSelected())方法,這樣就能及時刷新布局 mRecyclerView.setSelected(true); }else{ mSearchHistoryAdapter.notifyDataSetChanged(); } }private void initEvents() { //列表適配器的點擊監聽事件 mSearchHistoryAdapter.setOnItemClickLitener(new SearchHistoryAdapter.OnItemClickLitener() { @Override public void onItemClick(View view, int position) { Toast.makeText(MainActivity.this, mSearchHistoryBeanArrayList.get(position).getSearchTitle(), Toast.LENGTH_SHORT).show(); } }); } }
效果圖:
(2)如果在Adapter中添加以下代碼,效果圖則會發生變化(原理請閱讀《參考資料》)【這段代碼更適合用於圖片展示,這里是搜索記錄文本展現,不太合適】
package com.why.project.recyclerflexboxlayoutmanagerdemo.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.google.android.flexbox.AlignSelf; import com.google.android.flexbox.FlexboxLayoutManager; import com.why.project.recyclerflexboxlayoutmanagerdemo.R; import com.why.project.recyclerflexboxlayoutmanagerdemo.bean.SearchHistoryBean; import java.util.ArrayList; /** * Created by HaiyuKing * Used 搜索記錄列表適配器 */ public class SearchHistoryAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{ /**上下文*/ private Context myContext; /**頻道集合*/ private ArrayList<SearchHistoryBean> listitemList; /** * 構造函數 */ public SearchHistoryAdapter(Context context, ArrayList<SearchHistoryBean> itemlist) { myContext = context; listitemList = itemlist; } /** * 獲取總的條目數 */ @Override public int getItemCount() { return listitemList.size(); } /** * 創建ViewHolder */ @Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { View view = LayoutInflater.from(myContext).inflate(R.layout.searchhistory_list_item, parent, false); ItemViewHolder itemViewHolder = new ItemViewHolder(view); return itemViewHolder; } /** * 聲明grid列表項ViewHolder*/ static class ItemViewHolder extends RecyclerView.ViewHolder { public ItemViewHolder(View view) { super(view); listItemLayout = (LinearLayout) view.findViewById(R.id.listitem_layout); mTitle = (TextView) view.findViewById(R.id.tv_title); } LinearLayout listItemLayout; TextView mTitle; } /** * 將數據綁定至ViewHolder */ @Override public void onBindViewHolder(RecyclerView.ViewHolder viewHolder, int index) { //判斷屬於列表項還是上拉加載區域 if(viewHolder instanceof ItemViewHolder){ SearchHistoryBean searchHistoryBean = listitemList.get(index); final ItemViewHolder itemViewHold = ((ItemViewHolder)viewHolder); itemViewHold.mTitle.setText(searchHistoryBean.getSearchTitle()); ViewGroup.LayoutParams lp = itemViewHold.listItemLayout.getLayoutParams(); if (lp instanceof FlexboxLayoutManager.LayoutParams) { FlexboxLayoutManager.LayoutParams flexboxLp = (FlexboxLayoutManager.LayoutParams) itemViewHold.listItemLayout.getLayoutParams(); flexboxLp.setFlexGrow(1.0f); flexboxLp.setAlignSelf(AlignSelf.FLEX_END); } //如果設置了回調,則設置點擊事件 if (mOnItemClickLitener != null) { itemViewHold.listItemLayout.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { int position = itemViewHold.getLayoutPosition();//在增加數據或者減少數據時候,position和index就不一樣了 mOnItemClickLitener.onItemClick(itemViewHold.listItemLayout, position); } }); } } } /** * 添加Item--用於動畫的展現*/ public void addItem(int position,SearchHistoryBean listitemBean) { listitemList.add(position,listitemBean); notifyItemInserted(position); } /** * 刪除Item--用於動畫的展現*/ public void removeItem(int position) { listitemList.remove(position); notifyItemRemoved(position); } /*=====================添加OnItemClickListener回調================================*/ public interface OnItemClickLitener { void onItemClick(View view, int position); } private OnItemClickLitener mOnItemClickLitener; public void setOnItemClickLitener(OnItemClickLitener mOnItemClickLitener) { this.mOnItemClickLitener = mOnItemClickLitener; } }
效果圖
混淆配置
無
參考資料
Android可伸縮布局-FlexboxLayout(支持RecyclerView集成)
Google 開源的 Android 排版庫:FlexboxLayout
項目demo下載地址
https://github.com/haiyuKing/RecyclerFlexboxLayoutManagerDemo