在Android的无限滚动的ListView [英] Infinite listview scroll in android

问题描述

我有个任务做，我必须从本地数据库自定义列表视图，其布局包括2位和第2文本数据显示的数据。

I have a task to do in which I have to show data from a local database to custom listview whose layout includes 2 bitmap and 2 text data.

我曾尝试引用是：
  https://github.com/weixiao1984/Android-Infinite-Scroll-Listview。

但它有这么多，是让我困惑。

But it has so much that is making me confused.

推荐答案

试试这个

MainActivity.java

package com.example.endlesslistview;

import java.util.ArrayList;
import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.widget.AbsListView;
import android.widget.ProgressBar;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ListView;


public class MainActivity extends Activity {

    ListView lvTest;
    int index=0;
    ArrayList<ModelClass> model = new ArrayList<ModelClass>();
    AdapterClass adapter;
    ProgressBar progressbar;

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

        progressbar = (ProgressBar) findViewById(R.id.progressbar);
        lvTest = (ListView) findViewById(R.id.lvTest);
        insertData();
        adapter = new AdapterClass(MainActivity.this, model);
        lvTest.setAdapter(adapter);

        lvTest.setOnScrollListener(new EndlessScrollListener());
    }

    public void insertData(){
        for(int i=0;i<20;i++){
        model.add(new ModelClass("Data "+index, R.drawable.ic_launcher));
        index = index+1;
        }
    }

    public void insertNewData(){
        for(int i=0;i<20;i++){
        model.add(new ModelClass("Data "+index, R.drawable.ic_launcher));
        index = index+1;
        }

        adapter.notifyDataSetChanged();
    }


    public class EndlessScrollListener implements OnScrollListener {

        private int visibleThreshold = 20;
        private int currentPage = 0;
        private int previousTotal = 0;
        private boolean loading = true;

        public EndlessScrollListener() {
        }
        public EndlessScrollListener(int visibleThreshold) {
            this.visibleThreshold = visibleThreshold;
        }

        @Override
        public void onScroll(AbsListView view, int firstVisibleItem,
                int visibleItemCount, int totalItemCount) {
            if (loading) {
                if (totalItemCount > previousTotal) {
                    loading = false;
                    previousTotal = totalItemCount;
                    currentPage++;
                }
            }
            if (!loading && (totalItemCount - visibleItemCount) <= (firstVisibleItem + visibleThreshold)) {
                // I load the next page of gigs using a background task,
                // but you can call any function here.
                new ShowProgress().execute();
                loading = true;
            }
        }

        @Override
        public void onScrollStateChanged(AbsListView view, int scrollState) {
        }
    }

    class ShowProgress extends AsyncTask<Void, Void, Void>{


        @Override
        protected void onPreExecute() {
            progressbar.setVisibility(View.VISIBLE);
        }

        @Override
        protected Void doInBackground(Void... params) {
            // TODO Auto-generated method stub

            try {
                Thread.sleep(3000);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            progressbar.setVisibility(View.GONE);
            insertNewData();
        }
    }
}

activity_main.xml中

<FrameLayout 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"
    tools:context="com.example.endlesslistview.MainActivity" >

    <ListView
        android:id="@+id/lvTest"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
         >
    </ListView>

    <ProgressBar
        android:id="@+id/progressbar"
        style="?android:attr/progressBarStyle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:visibility="visible" />

</FrameLayout>

AdapterClass.java

package com.example.endlesslistview;
import java.util.ArrayList;

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

public class AdapterClass extends BaseAdapter{   
    Context context;
      private static LayoutInflater inflater=null;
      ArrayList<ModelClass> model;

    public AdapterClass(MainActivity mainActivity, ArrayList<ModelClass> model) {
        // TODO Auto-generated constructor stub
        this.model = model;
        context=mainActivity;
         inflater = ( LayoutInflater )context.
                 getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    }
    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return model.size();
    }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    public class Holder
    {
        TextView tv;
        ImageView img;
    }
    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        Holder holder=new Holder();
        View rowView;       
             rowView = inflater.inflate(R.layout.row_layout, null);
             holder.tv=(TextView) rowView.findViewById(R.id.textView1);
             holder.img=(ImageView) rowView.findViewById(R.id.imageView1);       
         holder.tv.setText(model.get(position).getData());
         holder.img.setImageResource(model.get(position).getImage());         
         rowView.setOnClickListener(new OnClickListener() {            
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Toast.makeText(context, "You Clicked "+model.get(position).getData(), Toast.LENGTH_LONG).show();
            }
        });   
        return rowView;
    }

} 

row_layout.xml

<?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:orientation="horizontal"
    android:layout_gravity="center_vertical"
    android:gravity="center_vertical" >

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher" />

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="TextView"
        android:layout_marginRight="10dp" />

</LinearLayout>

ModelClass.java

package com.example.endlesslistview;

public class ModelClass {

    String data;
    int image;

    public ModelClass(String data, int image) {
        this.data = data;
        this.image = image;
    }
    public String getData() {
        return data;
    }
    public void setData(String data) {
        this.data = data;
    }
    public int getImage() {
        return image;
    }
    public void setImage(int image) {
        this.image = image;
    }



}

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