2月5日学习总结

Posted 2021-03-12 1234yyf

今天观看视频学习了ListView,学习了属性跟点击事件；

需要自己新建一个java继承BaseAdapter

package com.example.yangy.myapplication1111111.ListView;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.yangy.myapplication1111111.R;

public class MyAdapter extends BaseAdapter {

    private Context mcontext;
    private LayoutInflater mLayoutInflater;
    MyAdapter(Context context){
    this.mcontext=context;
        mLayoutInflater=LayoutInflater.from(context);
    }

    @Override
    public int getCount() {
        return 10;
    }

    @Override
    public Object getItem(int position) {

        return null;
    }

    @Override
    public long getItemId(int position) {
        return 0;

    }

    static  class ViewHolder{
        public ImageView imageView;
        public TextView tv1;
        public TextView tv2;
    }
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
//列表每一行长什么样子
        ViewHolder holder=null;
        if(convertView==null){

            convertView=mLayoutInflater.inflate(R.layout.layout_list_item,null);
            holder=new ViewHolder();
            holder.imageView= (ImageView) convertView.findViewById(R.id.iv);
            holder.tv1= (TextView) convertView.findViewById(R.id.tv_title);
            holder.tv2= (TextView) convertView.findViewById(R.id.tv_time);
            convertView.setTag(holder);
        }else
        {
            holder= (ViewHolder) convertView.getTag();
        }
        //给控件赋值
        holder.tv1.setText("这是标题");
        holder.tv2.setText("这是时间2020-2-5");
        //Glide.with().load().into(holder.imageView);
        return convertView;
    }
}

View Code

然后在自己新建的ListView中的.xml中写布局

<ListView
    android:id="@+id/lv_1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:listSelector="@drawable/but4"//点击时候的样式>
然后在自己新建的Activity中的.xml中写上所需要的内容

<?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:orientation="horizontal"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.yangy.myapplication1111111.ListView.MyAdapter">
    <ImageView
        android:id="@+id/iv"
        android:layout_width="100dp"
        android:layout_height="100dp"
        android:background="#000"
        android:scaleType="centerCrop"/>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:layout_marginTop="20dp">
        <TextView
            android:id="@+id/tv_title"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="标题"
            android:layout_marginLeft="20dp"
            android:textColor="#000"
            android:textSize="20sp"/>
        <TextView
            android:id="@+id/tv_time"
            android:layout_marginTop="10dp"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="时间2020-02-05"
            android:layout_marginLeft="20dp"
            android:textColor="#000"
            android:textSize="20sp"/>
    </LinearLayout>

</LinearLayout>