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僅作為自己在使用recyclerview過程中一點點記錄，
- 使用Recyclerview已經(jīng)有一定時間插勤，項目中也用了很久沽瘦，總覺得該親自整理一下革骨，也算是自己回顧一下Recyclerview的知識，然后嘗試去深層次的了解Recyclerview析恋，只會用良哲，不了解，也不算是會用助隧；
- 如果你想嘗試Recyclerview筑凫，正好又看到這個文章，嗯哼0.0并村，那你就好好看看吧巍实。
- 廢話不多說，直接開整
首先當(dāng)然是添加依賴橘霎，根據(jù)當(dāng)前sdk版本蔫浆，選擇合適的依賴，Recyclerview是V7包提供的姐叁，所以呢瓦盛？
compile 'com.android.support:appcompat-v7:24.0.0'
compile 'com.android.support:recyclerview-v7:24.0.0'
第一個不必說，第二個就是我們需要的導(dǎo)入的包了外潜，rebuild一下原环，看看是否導(dǎo)入成功，只要根據(jù)自己使用的sdk版本处窥，一般是沒有意外的嘱吗，如果有了
很明顯是你導(dǎo)入錯了。
-
導(dǎo)入成功滔驾，接下來就是布局里使用了
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <android.support.v4.widget.SwipeRefreshLayout android:id="@+id/swipeRefresh" android:layout_width="match_parent" android:layout_height="match_parent"> <android.support.v7.widget.RecyclerView android:id="@+id/recyclerview" android:layout_width="match_parent" android:layout_height="match_parent" /> </android.support.v4.widget.SwipeRefreshLayout> </LinearLayout> -
布局很簡單谒麦，SwipeRefreshLayout包裹Recyclerview，實現(xiàn)下拉刷新
回到代碼中
public class MainActivity extends AppCompatActivity {
@InjectView(R.id.recyclerview)
RecyclerView recyclerview;
@InjectView(R.id.swipeRefresh)
SwipeRefreshLayout swipeRefresh;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.inject(this);
initData();
}
}
Recyclerview和SwipeRefreshLayout初始化完成哆致，開始加載數(shù)據(jù)實現(xiàn)Recyclerview的多種實現(xiàn)布局绕德；
有了數(shù)據(jù)之后，和ListView一樣摊阀，需要設(shè)置適配器耻蛇，但是Recyclerview得適配器和ListView適配器，不完全一樣胞此；假設(shè)Recyclerview適配器定義為Adapter
public class Adapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return null;
}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
}
@Override
public int getItemCount() {
return 0;
}
}
我們真正要實現(xiàn)的是重寫一個ViewHolder臣咖，繼承 Recyclerview.ViewHolder；
public class ItemHolder extends RecyclerView.ViewHolder {
public ItemHolder(View itemView) {
super(itemView);
}
}
設(shè)置Adapter的布局
<?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="60dp"
android:paddingLeft="10dp"
android:paddingTop="10dp">
<ImageView
android:id="@+id/imageView"
android:layout_width="40dp"
android:layout_height="40dp" />
<TextView
android:id="@+id/textView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center_vertical"
android:layout_marginLeft="15dp"
android:drawableBottom="@drawable/line"
android:ellipsize="end"
android:gravity="center_vertical"
android:text="123"
android:textColor="@color/colorAccent"
android:textSize="16sp" />
</LinearLayout>
</LinearLayout>
回到Adapter
public class Adapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private Context context;
private ArrayList<String> datas;
public Adapter(Context context, ArrayList<String> datas) {
this.context = context;
this.datas = datas;
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return new ItemHolder(LayoutInflater.from(context).inflate(R.layout.item_adapter, null));
}
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
}
@Override
public int getItemCount() {
return datas.size() == 0 ? 0 : datas.size();
}
public class ItemHolder extends RecyclerView.ViewHolder {
private ImageView imageView;
private TextView textView;
public ItemHolder(View itemView) {
super(itemView);
this.imageView = (ImageView) itemView.findViewById(R.id.imageView);
this.textView = (TextView) itemView.findViewById(R.id.textView);
}
}
}
最后數(shù)據(jù)綁定
/**
- Creation time : 2016/11/22 21:01
- Fix time : 2016/11/22 21:01
*/
public class Adapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
private Context context;
private List<String> datas;
public Adapter(Context context, List<String> datas) {
this.context = context;
this.datas = datas;
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return new ItemHolder(LayoutInflater.from(context).inflate(R.layout.item_adapter, null));
}
//綁定數(shù)據(jù)
@Override
public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
bindViewHolder((ItemHolder) holder);
}
private void bindViewHolder(ItemHolder holder) {
for (int i = 0; i < this.datas.size() - 1; i++) {
holder.textView.setText(datas.get(i));
holder.imageView.setBackgroundResource(R.drawable.musiclogo144);
}
}
@Override
public int getItemCount() {
return datas.size() == 0 ? 0 : datas.size();
}
public class ItemHolder extends RecyclerView.ViewHolder {
private ImageView imageView;
private TextView textView;
public ItemHolder(View itemView) {
super(itemView);
this.imageView = (ImageView) itemView.findViewById(R.id.imageView);
this.textView = (TextView) itemView.findViewById(R.id.textView);
}
}
}
回到加載數(shù)據(jù)部分
/**
* 請求數(shù)據(jù)
*/
private void initData() {
//假設(shè)聯(lián)網(wǎng)請求數(shù)據(jù)N條,這里我就用本地數(shù)據(jù)
data = null;
for (int i = 0; i < 40; i++) {
data.add(i, i + ". 成功請求數(shù)據(jù)");
}
adapter = new Adapter(MainActivity.this, data);
recyclerview.setAdapter(adapter);
}
編譯運行
但是什么都沒有漱牵，因為我們沒有設(shè)置LayoutManager夺蛇，Recyclerview需要設(shè)置LayoutManager，才能顯示酣胀；
public class MainActivity extends AppCompatActivity {
@InjectView(R.id.recyclerview)
RecyclerView recyclerview;
@InjectView(R.id.swipeRefresh)
SwipeRefreshLayout swipeRefresh;
private static final int GET = 1;
private LinearLayoutManager linearLayoutManager;
private GridLayoutManager gridLayoutManager;
private StaggeredGridLayoutManager staggeredGridLayoutManager;
private List<String> data;
private RecyclerView.LayoutManager layoutmanager;
private Adapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ButterKnife.inject(this);
linearLayoutManager = new LinearLayoutManager(MainActivity.this); //常見縱向布局
// linearLayoutManager = new LinearLayoutManager(MainActivity.this,LinearLayoutManager.HORIZONTAL,true); //水平方向刁赦，最后一個參數(shù)是否逆向
gridLayoutManager = new GridLayoutManager(MainActivity.this, 2); //類似GridView的格式愿卸，第二個參數(shù)為行的item數(shù)量，同理截型，也有水平方向的GridLayoutManager趴荸；
staggeredGridLayoutManager = new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL); //瀑布流，第一個為每行item數(shù)量
layoutmanager = linearLayoutManager; //默認(rèn)為縱向的Recyclerview宦焦；
initData();
}
@Override
public boolean onCreateOptionsMenu(Menu item) {
getMenuInflater().inflate(R.menu.main_menu, item);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.linearlayout:
layoutmanager = linearLayoutManager;
initData();
break;
case R.id.gridlayout:
layoutmanager = gridLayoutManager;
break;
case R.id.staggeredgridlayout:
layoutmanager = staggeredGridLayoutManager;
initData();
break;
default:
layoutmanager = linearLayoutManager;
initData();
break;
}
return super.onOptionsItemSelected(item);
}
/**
* 請求數(shù)據(jù)
*/
private void initData() {
//假設(shè)聯(lián)網(wǎng)請求數(shù)據(jù)N條,這里我就用本地數(shù)據(jù)
data = new ArrayList<>();
for (int i = 0; i < 40; i++) {
data.add(i + ". 成功請求數(shù)據(jù)");
}
recyclerview.setLayoutManager(layoutmanager);
adapter = new Adapter(MainActivity.this, data);
recyclerview.setHasFixedSize(true);
recyclerview.setAdapter(adapter);
}
}
默認(rèn)的LayoutManager
那么切換LayoutManager為GridLayoutManager发钝，效果會是什么樣呢
最后，切換到瀑布流
什么效果都沒有波闹，這是為什么呢酝豪，因為，設(shè)置瀑布流精堕，我們需要對item的間隙進行設(shè)置孵淘，不然沒有效果
首先自定義ItemDecoration
public class ItemDecoration extends RecyclerView.ItemDecoration {
private int space;
public ItemDecoration(int space) {
this.space = space;
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
outRect.left = space;
outRect.right = space;
outRect.bottom = space;
if (parent.getChildAdapterPosition(view) == 0) {
outRect.top = space;
}
}
}
設(shè)置間隙
* 請求數(shù)據(jù)
*/
private void initData() {
//假設(shè)聯(lián)網(wǎng)請求數(shù)據(jù)N條,這里我就用本地數(shù)據(jù)
data = new ArrayList<>();
for (int i = 0; i < 40; i++) {
data.add(i + ". 成功請求數(shù)據(jù)");
}
recyclerview.setLayoutManager(layoutmanager);
if(layoutmanager.equals(staggeredGridLayoutManager)) { //針對瀑布流，設(shè)置間隙
recyclerview.addItemDecoration(new ItemDecoration(15));
}
adapter = new Adapter(MainActivity.this, data);
recyclerview.setHasFixedSize(true);
recyclerview.setAdapter(adapter);
}
重新編譯運行歹篓，搞定
這算是Recyclerview的簡單使用瘫证，實現(xiàn)三種模式，已經(jīng)搞定庄撮，還有很多細(xì)節(jié)背捌，留到下一篇，仔細(xì)講解洞斯。
