Android实战简易教程-第二十四枪(基于Baas的用户表查询功能实现!)
接着上一篇,我们注冊了几个用户,用户表例如以下:
以下我们用ListView将表中数据显示出来吧。
首先看一下main.xml:
<RelativeLayout 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" >
<Button
android:id="@+id/btn_query"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="查询全部用户" />
<ListView
android:id="@+id/lv_users"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/btn_query" >
</ListView>
</RelativeLayout>然后MainActivity.java:
package com.example.listviewdemo;
import java.util.List;
import cn.bmob.v3.Bmob;
import cn.bmob.v3.BmobQuery;
import cn.bmob.v3.listener.FindListener;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Toast;
public class MainActivity extends Activity {
private Button mButtonQuery;
private ListView mListViewUsers;
private ListViewAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Bmob.initialize(this, "8f3ffb2658d8a3366a70a0b0ca0b71b2");// 初始化Bmob
mButtonQuery = (Button) findViewById(R.id.btn_query);
mListViewUsers = (ListView) findViewById(R.id.lv_users);
mButtonQuery.setOnClickListener(new OnClickListenerImpl());
}
private class OnClickListenerImpl implements OnClickListener {
@Override
public void onClick(View v) {
BmobQuery<User> query = new BmobQuery<User>();// 查询类
query.findObjects(MainActivity.this, new FindListener<User>() {
@Override
public void onSuccess(List<User> list) {
adapter = new ListViewAdapter(MainActivity.this, list);// 实例化
mListViewUsers.setAdapter(adapter);
}
@Override
public void onError(int arg0, String arg1) {
Toast.makeText(MainActivity.this, "查询失败!", 3).show();
}
});
}
}
}
ListViewAdapter.java:package com.example.listviewdemo;
import java.util.List;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;
public class ListViewAdapter extends BaseAdapter {
private Context context;
private List<User> list;
private LayoutInflater inflater;
public ListViewAdapter(Context context, List<User> list) {
this.context = context;
this.list = list;
inflater = LayoutInflater.from(context);
}
@Override
public int getCount() {
return list.size();
}
@Override
public Object getItem(int position) {
return list.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder viewHolder = null;
if (convertView == null) {
viewHolder = new ViewHolder();
convertView = inflater.inflate(R.layout.listview_item, null);
viewHolder.tv_idTextView = (TextView) convertView
.findViewById(R.id.tv_id);
viewHolder.tv_usernameTextView = (TextView) convertView
.findViewById(R.id.tv_username);
viewHolder.tv_userPasswordTextView = (TextView) convertView
.findViewById(R.id.tv_userpassword);
viewHolder.tv_timeTextView = (TextView) convertView
.findViewById(R.id.tv_time);
convertView.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) convertView.getTag();
}
viewHolder.tv_idTextView
.setText(list.get(position).getObjectId() + "|");
viewHolder.tv_usernameTextView.setText(list.get(position).getUserName()
+ "|");
viewHolder.tv_userPasswordTextView.setText(list.get(position)
.getUserPassword() + "|");
viewHolder.tv_timeTextView.setText(list.get(position).getCreatedAt());
return convertView;
}
class ViewHolder {
private TextView tv_idTextView;
private TextView tv_usernameTextView;
private TextView tv_userPasswordTextView;
private TextView tv_timeTextView;
}
}
list_item.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" >
<TextView
android:id="@+id/tv_id"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="@+id/tv_username"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="@+id/tv_userpassword"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="@+id/tv_time"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>User.java:
package com.example.logintest;
import cn.bmob.v3.BmobObject;
public class User extends BmobObject {
private String userPassword;
public String getUserPassword() {
return userPassword;
}
public void setUserPassword(String userPassword) {
this.userPassword = userPassword;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
private String userName;
}
最后配置文件:
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.listviewdemo" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" /> <uses-permission android:name="android.permission.INTERNET" /> <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /> <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> <uses-permission android:name="android.permission.READ_PHONE_STATE" /> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.READ_LOGS" /> <application android:allowBackup="true" android:icon="@drawable/ic_launcher" android:label="@string/app_name" android:theme="@style/AppTheme" > <activity android:name="com.example.listviewdemo.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest>
看一下文件:
执行实例:
喜欢的朋友关注我,谢谢!
浙公网安备 33010602011771号