Android support RecyclerView V7 framework: Introduction and use guide
Android support RecyclerView V7 framework: Introduction and use guide
Overview:
RecyclerView is a control in the Android support library to display a list or grid view of a large number of data sets in the application.Compared to the traditional ListView or GridView control, RecyclerView provides more flexible and efficient ways to manage and display data sets.RecyclerView supports custom layout and animation, and can achieve higher performance rolling and refresh.
user's guidance:
1. Import the recyclerView support library:
To use RecyclerView in the Android project, the RecyclerView V7 is needed to guide libraries into the project dependence.It can be implemented by adding subordinates to the project's Build.gradle file:
implementation 'androidx.recyclerview:recyclerview:1.0.0'
2. Add RecyclerView to the layout file:
In the layout file, add the RecyclerView control to the position that wants to display a list or grid.For example:
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/recyclerView"
android:layout_width="match_parent"
android:layout_height="match_parent" />
3. Create RecyclerView.adapter:
Create a adapter class that inherits RecyclerView.adapter, which will tell RecyclerView how to show and manage the data collection.In the adapter, the following methods need to be implemented:
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
// Create viewholder and initialize layout
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_layout, parent, false);
return new MyViewHolder(view);
}
@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
// Bind the data to the viewholder
holder.textView.setText(data.get(position));
}
@Override
public int getItemCount() {
// Back to the size of the data set
return data.size();
}
4. Create viewholder:
ViewHolder is used to cache the view of each list item to quickly access when rolling and refreshing.Create a ViewHolder class that inherits from the RecyclerView.ViewHolder, and initialize the control in it, such as::
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView textView;
public MyViewHolder(View itemView) {
super(itemView);
textView = itemView.findViewById(R.id.textView);
}
}
5. Set the layout manager and adapter of RecyclerView:
In activity or fragment, get reyclerView reference, and set the layout manager and adapter, such as:
RecyclerView recyclerView = findViewById(R.id.recyclerView);
recyclerView.setLayoutManager(new LinearLayoutManager(this));
recyclerView.setAdapter(adapter);
Through the above steps, you can successfully use the RecyclerView V7 framework to display and manage the list or grid view of the data set.
Summarize:
The RecyclerView V7 framework can help developers more flexible and efficiently display and manage a large number of data sets.This article introduces how to import the RecyclerView support library, how to add RecyclerView to the layout file, how to create a suitable for accessories and ViewHolder, and finally how to set the layout manager and adapter of the RecyclerView.I hope the content of this article will help developers using the RecyclerView V7 framework.
