xamarin下用c#開發安卓的listvew翻頁功能
listview的翻頁用到了幾個知識點,1資料的填充,2翻頁圖片的載入,3頁碼的計算,實際效果如下圖:
axml檔案有兩個,一個是主介面Main.axml,另一個是顯示“載入中。。。。”這個layout1.axml
Main.axml程式碼如下:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:minWidth="25px"
android:minHeight="25px">
<ListView
android:minWidth="25px"
android:minHeight="25px"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/listView1" />
</LinearLayout>
layout1.axml程式碼如下:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:minWidth="25px"
android:minHeight="25px">
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/linearLayout1"
android:gravity="center">
<ProgressBar
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:id="@+id/progressBar1" />
<TextView
android:text="載入中......"
android:textAppearance="?android:attr/textAppearanceLarge"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:id="@+id/textView1" />
</LinearLayout>
</LinearLayout>
程式檔案MainActivity.CS 如下:
using Android.App;
using Android.Widget;
using Android.OS;
using System.Collections.Generic;
using Android.Runtime;
using Android.Views;
namespace App12
{
[Activity(Label = "App12", MainLauncher = true)]
public class MainActivity : Activity
{
ListView list_member;
SimpleAdapter content;
int visiablecount;
int totalcount;
int first;
View foot ;
int pageindex =1 ;//當前頁碼
int pagesize =10; //每頁的條數
IList<IDictionary<string, object>> data;
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
SetContentView(Resource.Layout.Main);
list_member = FindViewById<ListView>(Resource.Id.listView1);
//填充資料
FillDate();
//顯示載入更多
// LayoutInflater inflater = LayoutInflater.UnregisterFromRuntime(this);
LayoutInflater inflater = LayoutInflater.FromContext(this);
foot = inflater.Inflate(Resource.Layout.layout1,null);
list_member.AddFooterView(foot);
//隱藏底部的載入圖示
foot.Visibility = ViewStates.Gone;
//listview拉倒底部
list_member.Scroll += List_member_Scroll;
// 滾動條狀態變化
list_member.ScrollStateChanged += List_member_ScrollStateChanged;
}
private void List_member_ScrollStateChanged(object sender, AbsListView.ScrollStateChangedEventArgs e)
{
// throw new System.NotImplementedException();
//判斷是否停止滾動
if (e.ScrollState == ScrollState.Idle && (first+visiablecount)==totalcount )
{
// Toast.MakeText(this, "滾動條停下來了!", ToastLength.Long).Show();
foot.Visibility = ViewStates.Visible; //顯示載入下一頁
pageindex++;
FillDate(); //填充資料到下頁
}
}
private void List_member_Scroll(object sender, AbsListView.ScrollEventArgs e)
{
//throw new System.NotImplementedException();
first = e.FirstVisibleItem; //第一項的編號
totalcount = e.TotalItemCount;//列表總條數
visiablecount = e.VisibleItemCount;//每頁條數
}
public void FillDate()
{
int PageEnd = pageindex * pagesize + 1; //當前頁最後一條資料的編號
int PageStart = (pageindex - 1) * pagesize;//當前頁最後一項的編號
data = new List<IDictionary<string, object>>();
//本程式會跟著 pageindex++無限迴圈翻頁
for (int i = 3; i < PageEnd; i++){
//我這裡面的資料是寫死的,有資料庫的同學可以連資料庫
JavaDictionary<string, object> achievement = new JavaDictionary<string, object>();
achievement.Add("title", "你好,我是張" + i);
achievement.Add("number","座號"+i);
data.Add(achievement);
}
//建立資料介面卡
content = new SimpleAdapter(
this,
data,
Android.Resource.Layout.SimpleListItem2,
new string[] { "title", "number" },
new int[] { Android.Resource.Id.Text1, Android.Resource.Id.Text2 });
//把資料繫結到list_member 這個listview上
list_member.Adapter = content;
list_member.SetSelection(PageStart); //當前頁第一項從哪頁開始
}
}
}
這個程式除錯了一段時間,希望大家玩的開心!
日行一善!
本專案在csdn的下載地址:
https://download.csdn.net/download/u014194297/10328782