[移动开发]android实现新闻框

MainActivity,java

package com.liuli.liebiao;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;

import java.text.SimpleDateFormat;
import java.util.Date;

public class MainActivity extends AppCompatActivity {
    String[] title = null;
    int[] image = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        title = new String[]{
                "考试测试题1",
                "考试测试题2",
                "考试测试题3",
                "考试测试题4"
        };

        image = new int[]{
                R.drawable.a,
                R.drawable.b,
                R.drawable.c,
                R.drawable.d,
        };

        ListView lv = findViewById(R.id.lv);



        //加分块
        View id1 = findViewById(R.id.b1);
        View id2 = findViewById(R.id.b2);
        id1.setOnClickListener(view ->{
            lv.setAdapter(new shxian());
        });
        id2.setOnClickListener(view ->{
            lv.setAdapter(null);
        });


    }
    class shxian extends BaseAdapter{

        @Override
        public int getCount() {
            return title.length;
        }

        @Override
        public Object getItem(int i) {
            return title[i];
        }

        @Override
        public long getItemId(int i) {
            return i;
        }

        @Override
        public View getView(int i, View view, ViewGroup viewgroup) {
            /*
            普通加分
            if (view == null) {
                view  = View.inflate(MainActivity.this,R.layout.lst_view_tem,null);
            }
            TextView titles = view.findViewById(R.id.title);
            TextView time = view.findViewById(R.id.time);
            ImageView img = view.findViewById(R.id.img);
            titles.setText(title[i]);
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-mm-dd");
            time.setText(sdf.format(new Date()));
            img.setImageResource(image[i]);

            return view;*/


            //多加分
            Hold hold = null;
            if (view == null) {
                view  = View.inflate(MainActivity.this,R.layout.lst_view_tem,null);

                hold = new Hold();
                hold.titles = view.findViewById(R.id.title);
                hold.time = view.findViewById(R.id.time);
                hold.img = view.findViewById(R.id.img);
                view.setTag(hold);
            }
            hold = (Hold)view.getTag();
            hold.titles.setText(title[i]);
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-mm-dd");
            hold.time.setText(sdf.format(new Date()));
            hold.img.setImageResource(image[i]);

            return view;
        }
    }
    class  Hold{
        TextView titles;
        TextView time;
        ImageView img;

    }
}

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activity_main.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:id="@+id/constraintLayout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <ListView
        android:id="@+id/lv"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_weight="1"/>
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:layout_constraintLeft_toLeftOf="parent"
            app:layout_constraintRight_toRightOf="parent"
            app:layout_constraintTop_toBottomOf="@+id/lv">

            <Button
                android:id="@+id/b1"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="按钮1" />

            <Button
                android:id="@+id/b2"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="按钮2" />

            <Button
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="按钮3" />

            <Button
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:text="按钮4" />
        </LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>

lst_view_tem

<?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="match_parent"
    android:padding="5dp"
    >
    <RelativeLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="1">

        <TextView
            android:id="@+id/title"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="考试测试题1"

            />

        <TextView
            android:id="@+id/time"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="2021-12-06"
            android:layout_alignBottom="@id/img"
            />

        <ImageView
            android:id="@+id/img"
            android:layout_width="160dp"
            android:layout_height="120dp"
            android:src="@drawable/a"
            android:layout_alignParentRight="true"/>
    </RelativeLayout>

</LinearLayout>