ANDROID RecyclerView V7 framework implementation method implementation method

In Android development, RecyclerView is a powerful and flexible control to display a large number of data lists.In order to make the list more diversified and beautiful, we often need to use a variety of layout types in RecyclerView.This article will introduce how to use the various layout type implementation methods in the Android Reyclerview V7 framework. First of all, we need to add RecyclerView dependencies to the project's Build.gradle file: implementation 'androidx.recyclerview:recyclerview:1.2.1' Next, we need to create a number of different layout files to represent different list items.For example, we create two layout files: `layout_item_type1.xml` and` layout_item_type2.xml` to represent two different types of list items. Next, we need to create a adapter class that inherits the RecyclerView.adapter to manage data and layout in RecyclerView. public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> { private static final int TYPE_1 = 0; private static final int TYPE_2 = 1; private List<MyItem> itemList; public MyAdapter(List<MyItem> itemList) { this.itemList = itemList; } // Return to the layout type according to the location @Override public int getItemViewType(int position) { if (itemList.get(position) instanceof Type1Item) { return TYPE_1; } else if (itemList.get(position) instanceof Type2Item) { return TYPE_2; } return -1; } // Create a new ViewHolder @Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { LayoutInflater layoutInflater = LayoutInflater.from(parent.getContext()); View view; if (viewType == TYPE_1) { view = layoutInflater.inflate(R.layout.layout_item_type1, parent, false); return new Type1ViewHolder(view); } else if (viewType == TYPE_2) { view = layoutInflater.inflate(R.layout.layout_item_type2, parent, false); return new Type2ViewHolder(view); } return null; } // Bind the data to viewholder @Override public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) { MyItem item = itemList.get(position); if (holder instanceof Type1ViewHolder) { Type1ViewHolder type1ViewHolder = (Type1ViewHolder) holder; // Assign and operate the controls in Type1Viewholder } else if (holder instanceof Type2ViewHolder) { Type2ViewHolder type2ViewHolder = (Type2ViewHolder) holder; // Assign and operate the controls in Type2Viewholder } } // Return to the number of columns @Override public int getItemCount() { return itemList.size(); } // Viewholder class definition private static class Type1ViewHolder extends RecyclerView.ViewHolder { // Definition of control in Type1viewholder // ... public Type1ViewHolder(View itemView) { super(itemView); // Type1Viewholder's control initialization // ... } } private static class Type2ViewHolder extends RecyclerView.ViewHolder { // Definition of control in Type2Viewholder // ... public Type2ViewHolder(View itemView) { super(itemView); // Type2Viewholder's control initialization // ... } } } In the adapter class, we use the GetItemViewType () method to determine the layout type of each list item.Then in the oncreateViewholder () method, we create the corresponding ViewHolder based on the layout type.Finally, in the OnbindViewHolder () method, we bind the data to the controls in each viewholder. Finally, in our Activity or Fragment, we can bind RecyclerView to the adapter class, and set the layout manager and layout type: RecyclerView recyclerView = findViewById(R.id.recyclerView); recyclerView.setLayoutManager(new LinearLayoutManager(this)); recyclerView.setAdapter(new MyAdapter(itemList)); Through the above steps, we can achieve a variety of layout types in the Android Reyclerview V7 framework.The layout type of each list item is determined by the getItemViewType () method in the adapter class, and then creates the corresponding ViewHolder based on the layout type, and the data is bound to the control in the ViewHolder.In this way, we can create a diverse ReyclerView list.