技術標籤：Android開發

ListView的實現步驟

1.單獨一行的佈局可以如下

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ImageView
        android:id="@+id/icon_image_view"
        android:layout_width="60dp"
        android:layout_height="60dp"
        android:src="@mipmap/ic_launcher_round"/>

    <TextView
        android:id="@+id/app_name_text_view"
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:textSize="20sp"
        android:padding="6dp"
        android:gravity="center_vertical"
        android:text="@string/app_name"/>
    
</LinearLayout>
 

2.adapter資料繫結

package com.sina.mythree;

import android.annotation.SuppressLint;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
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 androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.app.AppCompatDelegate;

import java.util.ArrayList;
import java.util.List;

public class AppListActivity extends AppCompatActivity {
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_app_list);

        ListView applistview = (ListView)findViewById(R.id.app_list_view);

        List<String> appNames = new ArrayList<>();

        appNames.add("QQ");
        appNames.add("weixin");
        appNames.add("Sina");

        applistview.setAdapter(new AppListAdapter(appNames));

    }

    //AppListAdapter 設定如下,並需要自己的佈局
    public class AppListAdapter extends BaseAdapter{


        List<String> mAppNames;
        public AppListAdapter(List<String> appNames)
        {
            mAppNames = appNames;
        }

        @Override
        public int getCount() {
            //有多少條資料
            return mAppNames.size();
        }

        @Override
        public Object getItem(int position) {
            //返回獲取當前資料位置
            return mAppNames.get(position);
        }

        @Override
        public long getItemId(int position) {
            //返回獲取當前資料的ID
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            //處理VIEW和DATA的適配填充過程

            //把XML載入JAVA
            LayoutInflater layoutInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            //把layout轉換成VIEW
            convertView = layoutInflater.inflate(R.layout.item_app_list_view,null);



            ImageView appIconImageView = (ImageView) convertView.findViewById(R.id.icon_image_view);
            TextView  appNameTextView = (TextView) convertView.findViewById(R.id.app_name_text_view);

            appNameTextView.setText(mAppNames.get(position));

            return convertView;
        }
    }

}
 

優化方向，在n個數據時候防止滑動卡頓，進行快取。