Android元件之RecyclerView的基本使用
阿新 • • 發佈:2018-12-30
效果圖
1.匯入依賴包
在build.gradle(Module:app)的dependencies中加入
compile ‘com.android.support:recyclerview-v7:25.1.0’
這裡的版本號與上下保持一致
2.在XML檔案中使用
activity_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.csdn.csdn.MainActivity">
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/recyclerView" />
</RelativeLayout>
item.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:layout_width="match_parent"
android:layout_height ="80dp"
android:id="@+id/textView"/>
</LinearLayout>
3.在Java檔案中載入
recyclerView = (RecyclerView) findViewById(R.id.recyclerview);
//設定豎向佈局
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
/*************************
*佈局有三種選擇:
*LinerlayoutManager(豎向)
*GridLayoutManager(橫向)
*StaggeredGirdLayoutManager(瀑布流式)
***********************/
//載入佈局
recyclerView.setLayoutManager(linearLayoutManager);
//高度固定,不是瀑布流時可以節省資源
recyclerView.setHasFixedSize(true);
//設定Adapter
adapter = new Adapter(dataset);
recyclerView.setAdapter(adapter);
此外dataset一般還要進行初始化
private void initDataset() {
dataset = new String[10];
for (int i = 0; i < 10; i++) {
dataset[i] = ("item" + i);
}
}
RecyclerView的使用
4.編寫Adapter
Adapter需要繼承 RecyclerView,並且複寫3個方法:
onCreateViewHolder
onBindViewHolder
getItemCount
(1)onCreateViewHolder
public Adapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
//獲取父容器parent,向parent中填充item子容器。即關聯item佈局
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item, parent, false);
ViewHolder viewHolder = new ViewHolder(view);
return viewHolder;
}
(2)onBindViewHolder
//繫結ViewHolder,即載入資料
public void onBindViewHolder(Adapter.ViewHolder holder, int position) {
holder.textView.setText(dataset[position]);
}
(3)getItemCount
//獲取item數目
public int getItemCount() {
return mDataset.size();
}
此外一般還有再寫構造器方法與ViewHolder方法
構造器方法用於資料的初始化
//初始化資料
public MyAdapter(List<> mDataSet) {
this.mDataset = mDataSet;
}
ViewHolder方法用於元件的初始化
//載入並初始化元件
public static class ViewHolder extends RecyclerView.ViewHolder {
TextView name, teacher, detail, day, type, credit;
public ViewHolder(View v) {
super (v);
name = (TextView) v.findViewById(R.id.name);
teacher = (TextView) v.findViewById(R.id.teacher);
detail = (TextView) v.findViewById(R.id.detail);
day = (TextView) v.findViewById(R.id.day);
type = (TextView) v.findViewById(R.id.type);
credit = (TextView) v.findViewById(R.id.credit);
}
}