編輯:關於Android編程
通過ContentResolver操作內容提供者的數據,將姓名,電話顯示在listView中,並帶有添加和刪除按鈕進行相應操作





activity_user_update.xml
package com.example.android_provider;
import android.app.Activity;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.content.pm.LabeledIntent;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.widget.CursorAdapter;
import android.support.v4.widget.SimpleCursorAdapter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity {
private ListView lv_user;
// 內容解析器
private ContentResolver contentResolver;
// 操作的標志
private static final String AUTHORITIE = "www.csdn.com.provider.userContentProvider";
// 請求碼
int requestUpdCode = 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// 模型層
// 創建內容解析器對象
contentResolver = getContentResolver();
lv_user = (ListView) findViewById(R.id.listView1);
initData();
}
/**
* 查找數據
*/
private void initData() {
// 控制層(自定義)
Cursor c = contentResolver.query(
Uri.parse("content://" + AUTHORITIE + "/query"), new String[] {
"userid as _id", "username", "userage", "usersalary",
"userphone" }, null, null, null);
MyCursorAapter adapter = new MyCursorAapter(this, c,
CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER);
// 視圖層
lv_user.setAdapter(adapter);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// 請求碼
if (requestCode == requestUpdCode) {
// 結果碼
if (resultCode == 2) {
// 傳過來的數據
if (data.getIntExtra("count", 0) > 0) {
initData();// 重新加載界面
Toast.makeText(this, "更新成功", 0).show();
} else {
Toast.makeText(this, "更新失敗", 0).show();
}
}
}
}
class MyCursorAapter extends CursorAdapter {
// 上下文對象
private Context context;
// 打氣筒,布局服務對象
private LayoutInflater mInflater;
// 構造器
public MyCursorAapter(Context context, Cursor c, int flags) {
super(context, c, flags);
this.context = context;
mInflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
// mInflater服務通過inflate方法返回一個View控件對象
// 通過自己的布局文件轉化的View對象,轉化之後就可以在bindView處理
// 先new出當前的布局。new出每一個條目的布局文件。
// new出當前布局,bindView中就可以用findViewById去拿控件
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
return mInflater.inflate(R.layout.list_item_user, parent, false);
}
@Override
public void bindView(View view, Context context, Cursor cursor) {
// 查找組件
Button btn_del = (Button) view.findViewById(R.id.btn_delete);
Button btn_upd = (Button) view.findViewById(R.id.btn_update);
TextView tv_name = (TextView) view.findViewById(R.id.tv_name);
TextView tv_phone = (TextView) view.findViewById(R.id.tv_phone);
// 設置值
tv_name.setText(cursor.getString(cursor.getColumnIndex("username")));
tv_phone.setText(cursor.getString(cursor
.getColumnIndex("userphone")));
// 根據id刪除
final int _id = cursor.getInt(cursor.getColumnIndex("_id"));
final String name = cursor.getString(cursor
.getColumnIndex("username"));
// 刪除按鈕的注冊事件
btn_del.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// 通過內容解析器刪除
int count = contentResolver.delete(
Uri.parse("content://" + AUTHORITIE + "/delete"),
"userid=?", new String[] { _id + "" });
if (count > 0) {
Toast.makeText(MainActivity.this, "成功刪除掉" + name,
Toast.LENGTH_LONG).show();
// 刪除後重新加載
initData();
}
}
});
// 根據每條更新
final String age = cursor.getString(cursor
.getColumnIndex("userage"));
final String salary = cursor.getString(cursor
.getColumnIndex("usersalary"));
final String phone = cursor.getString(cursor
.getColumnIndex("userphone"));
// 更新按鈕的注冊事件
btn_upd.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent();
intent.putExtra("uid", _id);
intent.putExtra("uname", name);
intent.putExtra("uage", age);
intent.putExtra("usalary", salary);
intent.putExtra("uphone", phone);
intent.setClass(getApplicationContext(),
UserUpdateActivity.class);
startActivityForResult(intent, requestUpdCode);
}
});
}
}
}
package com.example.android_provider;
import android.app.Activity;
import android.content.ContentResolver;
import android.content.ContentValues;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
public class UserUpdateActivity extends Activity {
// 內容解析器
private ContentResolver contentResolver;
// 操作的標志
private static final String AUTHORITIE = "www.csdn.com.provider.userContentProvider";
private EditText etName, etAge, etSalary, etId, etPhone;
// 結果碼
private int resultCode = 2;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_user_update);
findView();
// 獲取意圖對象
Intent intent = getIntent();
// 給控件設置intent傳過來的值 是數字都必須加“”轉為字符串
etId.setText(intent.getIntExtra("uid", 0) + "");
etName.setText(intent.getStringExtra("uname"));
etAge.setText(intent.getIntExtra("uage", 18) + "");
etSalary.setText(intent.getDoubleExtra("usalary", 0) + "");
etPhone.setText(intent.getStringExtra("uphone"));
// 創建解析器對象
contentResolver = getContentResolver();
}
// 查找控件
public void findView() {
etId = (EditText) findViewById(R.id.ed_upd_id);
etName = (EditText) findViewById(R.id.ed_upd_name);
etAge = (EditText) findViewById(R.id.ed_upd_age);
etSalary = (EditText) findViewById(R.id.ed_upd_salary);
etPhone = (EditText) findViewById(R.id.ed_upd_phone);
}
public void update(View v) {
String uid = etId.getText().toString().trim();
String uname = etName.getText().toString().trim();
String uage = etAge.getText().toString().trim();
String usalart = etSalary.getText().toString().trim();
String uphone = etPhone.getText().toString().trim();
// values.put(key, value)put的key值必須是數據庫裡的值
ContentValues values = new ContentValues();
values.put("userid", uid);
values.put("username", uname);
values.put("userage", uage);
values.put("usersalary", usalart);
values.put("userphone", uphone);
int count = contentResolver.update(
Uri.parse("content://" + AUTHORITIE + "/update"), values,
"userid=?", new String[] { uid });
Intent intent = new Intent();
intent.putExtra("count", count);
UserUpdateActivity.this.setResult(resultCode, intent);
// 關閉資源
this.finish();
}
}
// 構造器
public MyCursorAapter(Context context, Cursor c, int flags) {
super(context, c, flags);
this.context = context;
mInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
mInflater充當打氣筒的角色,布局服務對象
mInflater服務通過inflate方法返回一個View控件對象
通過自己的布局文件轉化的View對象,轉化之後就可以在bindView處理
先new出當前的布局,new出每一個條目的布局文件。
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
return mInflater.inflate(R.layout.list_item_user, parent, false);
}
//設置值
tv_name.setText(cursor.getString(cursor.getColumnIndex("username")));
tv_phone.setText(cursor.getString(cursor
.getColumnIndex("userphone")));cursor.getString():cursor對應列的值
當你關閉activity時有返回值的情況下用startActivityForResult方法,並通過重新onActivityResult方法處理
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// 請求碼
if (requestCode == requestUpdCode) {
// 結果碼
if (resultCode == 2) {
// 傳過來的數據
if (data.getIntExtra("count", 0) > 0) {
initData();// 重新加載界面
Toast.makeText(this, "更新成功", 0).show();
} else {
Toast.makeText(this, "更新失敗", 0).show();
}
}
}
}給控件設置intent傳過來的值 是數字都必須加“”轉為字符串
// 獲取意圖對象
Intent intent = getIntent();
// 給控件設置intent傳過來的值 是數字都必須加“”轉為字符串
etId.setText(intent.getIntExtra("uid", 0) + "");
etName.setText(intent.getStringExtra("uname"));
etAge.setText(intent.getIntExtra("uage", 18) + "");
etSalary.setText(intent.getDoubleExtra("usalary", 0) + "");
etPhone.setText(intent.getStringExtra("uphone"));
<喎?/kf/ware/vc/" target="_blank" class="keylink">vcD4KPHByZSBjbGFzcz0="brush:java;"> ContentValues values = new ContentValues(); values.put("userid", uid); values.put("username", uname); values.put("userage", uage); values.put("usersalary", usalart); values.put("userphone", uphone);
put的key值必須是數據庫裡的值
轉載請標明轉載地址:http://blog.csdn.net/zhaoyazhi2129/article/details/29875555
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