类微信的门户页面框架设计（2）

ps：这回衔接的是老师给的代码，和之前作业关系不大

一、主要内容
1.在“联系人”栏用recycleview实现滚动列表

2.点击列表进入详情界面

二、核心代码

(1)layout中新增
编写RecyclerView滚动列表中的行样式文件item.xml

<?xml version="1.0" encoding="utf-8"?>
<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:id="@+id/textView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:gravity="center"
        android:text="这是列表项的某一行。"
        android:textSize="25sp" />

    <TextView
        android:id="@+id/textView2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_weight="1"
        android:gravity="center"
        android:text=""
        android:textSize="25sp" />
</LinearLayout>

点击进去后显示activity_item.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".ItemActivity">


    <TextView
        android:id="@+id/itemtextView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:text="查看详情"
        android:textSize="30dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.221" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="点我"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.498"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.368" />

    <TextView
        android:id="@+id/itemtextView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginStart="32dp"
        android:layout_marginEnd="32dp"
        android:gravity="center"
        android:text="这是返回信息"
        android:textSize="30dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.597" />
</androidx.constraintlayout.widget.ConstraintLayout>

（2）java新增

Adapter.class继承自RecyclerView.Adapter:

package com.example.work2;

import android.content.Context;

import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.lifecycle.ViewTreeViewModelStoreOwner;
import androidx.recyclerview.widget.RecyclerView;

import java.util.List;

public class Adapter extends RecyclerView.Adapter<Adapter.myviewholder> {

    private List<String> list;
    private Context context;
    private View inflater;

    public Adapter(Context context, List<String> list) {
        this.context = context;
        this.list = list;
    }

    @Override
    public myviewholder onCreateViewHolder(ViewGroup viewGroup, int i) {
        inflater = LayoutInflater.from(context).inflate(R.layout.item, viewGroup, false);
        myviewholder myviewholder = new myviewholder(inflater);
        return myviewholder;
    }


    @Override
    public void onBindViewHolder(myviewholder myviewholder, int j) {
        myviewholder.textView.setText(list.get(j));
        myviewholder.textView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent=new Intent(context,ItemActivity.class);
                context.startActivity(intent);
            }
        });
    }

    @Override
    public int getItemCount() {
        return list.size();
    }


     class myviewholder extends RecyclerView.ViewHolder{
        TextView textView;
        public myviewholder( View itemView) {
            super(itemView);
            textView = itemView.findViewById(R.id.textView2);
        }
    }

}

itemActivity.java：点击列表进入界面

package com.example.work2;

import androidx.activity.result.ActivityResult;
import androidx.activity.result.ActivityResultCallback;
import androidx.activity.result.ActivityResultLauncher;
import androidx.activity.result.contract.ActivityResultContracts;
import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class ItemActivity extends AppCompatActivity {
    private Button button;
    private TextView textView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_item);

        textView=findViewById(R.id.itemtextView2);

        button = findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(ItemActivity.this,resultActivity.class);
                test.launch(intent);
            }
        });
    }

        public ActivityResultLauncher test = registerForActivityResult(
                new ActivityResultContracts.StartActivityForResult(),
                new ActivityResultCallback<ActivityResult>() {

                    @Override
                    public void onActivityResult(ActivityResult result) {
                        if (result.getResultCode() == 666) {
                            Log.d("xr", "onActivityResult...");
                            textView.setText(result.getData().getStringExtra("data"));
                        }
                    }
                }
        );
    }

 resultActivity.java：返回信息

package com.example.work2;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.util.Log;

import java.util.Calendar;

public class resultActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_result);
        Intent intent=getIntent();
        intent.putExtra("data","哈哈哈哈哈哈哈哈");
        setResult(666,intent);
        finish();
    }
}

三、结果展示

四、仓库地址

类微信作业