learning target:
1. Use the circulator view
2. Use case demonstration
Learning Content:
1. Circulator view.
setAdapter: Set the adapter of the list item. See the next heading for a detailed description of the adapter. setLayoutManager:
Set the layout manager of the list item. There are currently three types, namely: Linear Layout Manager LinearLayoutManager, Grid Layout Manager GridLayoutManager, Waterfall Grid Layout Manager StaggeredGridLayoutManager. For a detailed description of the layout manager, see the second half of this article.
addItemDecoration: Add the dividing line of the list item. removeItemDecoration: Remove the dividing line of the list item.
setItemAnimator: Set the addition and deletion animation of list items. addOnItemTouchListener:
Add a touch listener for list items. Because RecyclerView does not implement the click interface of list items, developers can monitor user gestures through the touch listener here.
removeOnItemTouchListener: Remove the touch listener for the list item.
2. Case demonstration
1. Create a new project and add a dependency on the recyclerview library. It
takes a while to load.
2. Write in the activity_main.xml file
<?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:background="@drawable/background"
android:padding="15dp"
tools:context=".MainActivity">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/rvStudent"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</LinearLayout>
3. Create a new xml in the layout, used in the main method, the frame
<?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="wrap_content"
android:gravity="center_vertical"
android:orientation="horizontal">
<ImageView
android:id="@+id/ivStudentIcon"
android:layout_width="60dp"
android:layout_height="60dp" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:layout_marginBottom="10dp"
android:gravity="center_vertical"
android:orientation="vertical">
<TextView
android:id="@+id/tvStudentName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:textColor="#0000ff"
android:textSize="25sp" />
<TextView
android:id="@+id/tvStudentPhone"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="30dp"
android:textColor="#555555"
android:textSize="20sp" />
</LinearLayout>
</LinearLayout>
3. Main method write
package com.example.myapplication;;
import android.annotation.SuppressLint;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.DividerItemDecoration;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.OrientationHelper;
import androidx.recyclerview.widget.RecyclerView;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
private RecyclerView rvStudent; // 学生循环器视图（展示）
private RecyclerView.Adapter adapter; // 循环器适配器（桥梁）
private List<Student> students; // 学生列表（数据源）
@SuppressLint("WrongConstant")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// 利用布局资源文件设置用户界面
setContentView(R.layout.activity_main);
// 通过资源标识符获取控件实例
rvStudent = findViewById(R.id.rvStudent);
// 获取学生列表作为数据源
students = getStudents();
// 创建线性布局管理器
LinearLayoutManager layoutManager = new LinearLayoutManager(this);
// 设置线性布局管理器方向属性（默认是VERTICAL）
layoutManager.setOrientation(OrientationHelper.VERTICAL);
// 给循环器视图设置布局管理器
rvStudent.setLayoutManager(layoutManager);
// 初始化循环器适配器
adapter = new RecyclerView.Adapter() {
/**
* 视图容器
*/
class ViewHolder extends RecyclerView.ViewHolder {
private ImageView ivStudentIcon;
private TextView tvStudentName;
private TextView tvStudentPhone;
public ViewHolder(@NonNull View itemView, ImageView ivStudentIcon, TextView tvStudentName, TextView tvStudentPhone) {
super(itemView);
this.ivStudentIcon = ivStudentIcon;
this.tvStudentName = tvStudentName;
this.tvStudentPhone = tvStudentPhone;
}
public ImageView getIvStudentIcon() {
return ivStudentIcon;
}
public TextView getTvStudentName() {
return tvStudentName;
}
public TextView getTvStudentPhone() {
return tvStudentPhone;
}
}
@NonNull
@Override
public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
// 获取视图对象（将列表项模板转换成视图）
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.student_list_item, parent, false);
// 获取视图里的控件
ImageView ivStudentIcon = view.findViewById(R.id.ivStudentIcon);
TextView tvStudentName = view.findViewById(R.id.tvStudentName);
TextView tvStudentPhone = view.findViewById(R.id.tvStudentPhone);
// 创建视图容器
RecyclerView.ViewHolder viewHolder = new ViewHolder(view, ivStudentIcon, tvStudentName, tvStudentPhone);
// 返回视图容器
return viewHolder;
}
@Override
public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
// 获取学生数据
Student student = students.get(position);
// 获取控件实例
ImageView ivStudentIcon = ((ViewHolder)holder).getIvStudentIcon();
TextView tvStudentName = ((ViewHolder)holder).getTvStudentName();
TextView tvStudentPhone = ((ViewHolder)holder).getTvStudentPhone();
// 设置控件属性
ivStudentIcon.setImageResource(student.getStudentIcon());
tvStudentName.setText(student.getStudentName());
tvStudentPhone.setText(student.getStudentPhone());
// 给控件设置监听器
ivStudentIcon.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(MainActivity.this, student.getStudentName()
+ " : " + student.getStudentPhone(), Toast.LENGTH_SHORT).show();
}
});
tvStudentName.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(MainActivity.this, student.getStudentName()
+ " : " + student.getStudentPhone(), Toast.LENGTH_SHORT).show();
}
});
tvStudentPhone.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Toast.makeText(MainActivity.this, student.getStudentName()
+ " : " + student.getStudentPhone(), Toast.LENGTH_SHORT).show();
}
});
}
@Override
public int getItemCount() {
return students.size();
}
};
// 给循环器视图设置适配器
rvStudent.setAdapter(adapter);
// 给循环器视图添加列表项分隔线
rvStudent.addItemDecoration(new DividerItemDecoration(this, DividerItemDecoration.VERTICAL));
}
/**
* @return 学生列表
*/
private List<Student> getStudents() {
// 创建学生列表
List<Student> students = new ArrayList<>();
// 声明学生
Student student = null;
// 创建第1个学生
student = new Student();
student.setStudentIcon(R.drawable.img1);
student.setStudentName("李晓红");
student.setStudentPhone("15878782345");
// 将学生添加到学生列表
students.add(student);
// 创建第2个学生
student = new Student();
student.setStudentIcon(R.drawable.img2);
student.setStudentName("王晓玲");
student.setStudentPhone("15956567890");
// 将学生添加到学生列表
students.add(student);
// 创建第3个学生
student = new Student();
student.setStudentIcon(R.drawable.img3);
student.setStudentName("董大伟");
student.setStudentPhone("13567891230");
// 将学生添加到学生列表
students.add(student);
// 创建第4个学生
student = new Student();
student.setStudentIcon(R.drawable.img4);
student.setStudentName("尚洪文");
student.setStudentPhone("18856789032");
// 将学生添加到学生列表
students.add(student);
// 创建第5个学生
student = new Student();
student.setStudentIcon(R.drawable.img5);
student.setStudentName("唐语涵");
student.setStudentPhone("15967893450");
// 将学生添加到学生列表
students.add(student);
// 创建第6个学生
student = new Student();
student.setStudentIcon(R.drawable.img6);
student.setStudentName("郑智化");
student.setStudentPhone("15867678904");
// 将学生添加到学生列表
students.add(student);
// 创建第7个学生
student = new Student();
student.setStudentIcon(R.drawable.img7);
student.setStudentName("童安格");
student.setStudentPhone("13845674560");
// 将学生添加到学生列表
students.add(student);
// 返回学生列表
return students;
}
}
4. Create a new class
package com.example.myapplication;
public class Student {
private int studentIcon;
private String studentName;
private String studentPhone;
public int getStudentIcon() {
return studentIcon;
}
public void setStudentIcon(int studentIcon) {
this.studentIcon = studentIcon;
}
public String getStudentName() {
return studentName;
}
public void setStudentName(String studentName) {
this.studentName = studentName;
}
public String getStudentPhone() {
return studentPhone;
}
public void setStudentPhone(String studentPhone) {
this.studentPhone = studentPhone;
}
@Override
public String toString() {
return "Student{" +
"studentIcon=" + studentIcon +
", studentName='" + studentName + '\'' +
", studentPhone='" + studentPhone + '\'' +
'}';
}
}
Operation results
Tomorrow to learn about the network interface, realize the android stuidio connection network interface, use the post, get method request.