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Android開發實現上一頁,下一頁顯示內容

最近寫了個上一頁下一頁顯示Demo,感覺還是比較好實現!通過設定listview的每頁item顯示的個數,然後控制返回item的count實現點選按鈕上一頁下一頁效果.

一,佈局檔案(若是想實現滑動的上一頁和下一頁切換直接使用ViewPager巢狀listview)

<?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="vertical" tools:context="com.tstest.www.pagershow.MainActivity">
<TextView android:id="@+id/result" android:layout_width="wrap_content" android:layout_height
="wrap_content" android:text="為你搜索到如下結果:" android:textSize="18sp" />
<TextView android:id="@+id/num" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center" android:text="2/4" android:textSize
="18sp" />
<LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal"> <Button android:id="@+id/pre_pager" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="上一頁" /> <Button android:id="@+id/nex_pager" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="10dp" android:text="下一頁" /> </LinearLayout> <ListView android:id="@+id/lv" android:layout_width="wrap_content" android:layout_height="wrap_content" /> </LinearLayout>

二,實現程式碼,這個demo做的是當在第一頁時隱藏上一頁按鈕,最後一頁時隱藏下一頁按鈕.中間上一頁按鈕和下一頁按鈕皆顯示.

package com.tstest.www.pagershow;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;

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

public class MainActivity extends AppCompatActivity implements View.OnClickListener{
    private List<NearlySearchBean> list=new ArrayList<>();
    private String name[]={"gaga","嘎嘎","他們嗎","發密碼","摩爾瑪","陪我"};
    private ListViewAdapter adapter;
    private Button prePager, nexPager;
    private TextView num;
    private NearlySearchBean nearlySearchBean;
    int index=0;
    int pagerCount=4;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        prePager = (Button) findViewById(R.id.pre_pager);
        nexPager = (Button) findViewById(R.id.nex_pager);
        num = (TextView) findViewById(R.id.num);
        ListView listView = (ListView) findViewById(R.id.lv);
        for (int i = 0; i < name.length; i++) {
            nearlySearchBean = new NearlySearchBean();
            nearlySearchBean.setName(name[i]);
            list.add(nearlySearchBean);
        }
        prePager.setOnClickListener(this);
        nexPager.setOnClickListener(this);
        adapter = new ListViewAdapter();
        listView.setAdapter(adapter);
        prePager.setVisibility(View.INVISIBLE);
        num.setText(index+1+"/"+(int) Math.ceil((double)list.size()/pagerCount));
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()){
            case R.id.pre_pager:
                prePager();
                break;
            case R.id.nex_pager:
                nexPager();
                break;
        }
    }

    private void nexPager() {
        index++;
        System.out.println(index+"nexPager");
        num.setText(index+1+"/"+(int) Math.ceil((double)list.size()/pagerCount));
        adapter .notifyDataSetChanged();
        //隱藏上一個或下一個按鈕
        checkButton();
    }

    private void checkButton() {
        if (index<=0){
            prePager.setVisibility(View.INVISIBLE);
            nexPager.setVisibility(View.VISIBLE);
        }else if (list.size()-index*pagerCount<=pagerCount){    //資料總數減每頁數當小於每頁可顯示的數字時既是最後一頁
            nexPager.setVisibility(View.INVISIBLE);
            prePager.setVisibility(View.VISIBLE);
        }
    }

    private void prePager() {
        index--;
        System.out.println(index+"prePager");
        adapter.notifyDataSetChanged();
        num.setText(index+1+"/"+(int) Math.ceil((double)list.size()/pagerCount));
        //隱藏上一個或下一個按鈕
        checkButton();
    }
    class ListViewAdapter extends BaseAdapter{

        @Override
        public int getCount() {
            //資料大於頁數*每頁個數,顯示預設數字,小於時顯示剩餘的
            int current = index * pagerCount;
            return list.size()-current<pagerCount?list.size()-current:pagerCount;
        }

        @Override
        public Object getItem(int i) {
            return null;
        }

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

        @Override
        public View getView(int position, View convertView, ViewGroup viewGroup) {
            convertView= LayoutInflater.from(getApplicationContext()).inflate(R.layout.pager_item,viewGroup,false);
            TextView name = (TextView) convertView.findViewById(R.id.name);
            int pos = position + index * pagerCount;
            NearlySearchBean nearlySearchBean = list.get(pos);
            name.setText(nearlySearchBean.getName());
            return convertView;
        }
    }
}

三,item佈局和Javabean,Javabean可以根據自己顯示的內容增減


public class NearlySearchBean {
    private String name;
    private String instance;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getInstance() {
        return instance;
    }

    public void setInstance(String instance) {
        this.instance = instance;
    }
}


<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:id="@+id/name"
        android:layout_width="wrap_content"
        android:text="肯德基"
        android:textSize="24sp"
        android:textColor="@color/colorAccent"
        android:layout_height="wrap_content" />
</RelativeLayout>