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應(yīng)用場景：
在Android官方指出的Android的數(shù)據(jù)存儲方式總共有五種，分別是：Shared Preferences、網(wǎng)絡(luò)存儲、文件存儲、外儲存儲、SQLite。但是我們知道一般這些存儲都只是在單獨(dú)的一個應(yīng)用程序之中達(dá)到一個數(shù)據(jù)的共享，而且這些知識在前面我都有介紹，有時候我們需要操作其他應(yīng)用程序的一些數(shù)據(jù)，例如我們需要操作系統(tǒng)里的媒體庫、通訊錄等，這時我們就可能通過ContentProvider來滿足我們的需求了
ContentProvider概述：
ContentProvider向我們提供了我們在應(yīng)用程序之前共享數(shù)據(jù)的一種機(jī)制，而我們知道每一個應(yīng)用程序都是運(yùn)行在不同的應(yīng)用程序的，數(shù)據(jù)和文件在不同應(yīng)用程序之間達(dá)到數(shù)據(jù)的共享不是沒有可能，而是顯得比較復(fù)雜，而正好Android中的ContentProvider則達(dá)到了這一需求，比如有時候我們需要操作手機(jī)里的聯(lián)系人，手機(jī)里的多媒體等一些信息，我們都可以用到這個ContentProvider來達(dá)到我們所需。
如何理解ContentProvider
上面說了一大堆ContentProvider的概述，可能大家還是不太特別理解ContentProvider到底是干什么的，那么我們以一個網(wǎng)站來形象的描述這個ContentProvider吧，可以這么理解為ContentProvider就是一個網(wǎng)站，它向我們?nèi)ピL問網(wǎng)站這里的數(shù)據(jù)達(dá)到了一種可能，它就是一個向外提供數(shù)據(jù)的接口。那么既然它是向外提供數(shù)據(jù)，我們有時候也需要去修改數(shù)據(jù)，這時我們就可以用到另外一個類來實(shí)現(xiàn)這個對數(shù)據(jù)的修改ContentResolver類，這個類就可以通過URI來操作數(shù)據(jù)。至于這些類的作用及描述在下面就會一一的介紹到。
如何實(shí)現(xiàn)ContentProvider
理解了ContentProvider類，那么我們怎么去實(shí)現(xiàn)ContentProvider呢？怎么樣讓外部程序去訪問或者修改我們的數(shù)據(jù)呢？這樣的一個操作其實(shí)是非常簡單的，我們只需要下面的兩步就可以實(shí)現(xiàn)ContentProvider
1、? 編寫一個實(shí)現(xiàn)ContentProvider的在，這個子類必須要實(shí)現(xiàn)一些必須實(shí)現(xiàn)的方法，在ContentProvider類里面，有一系列針對于數(shù)據(jù)的增、刪、改、查等方法
2、? ContentProvider也是Android中的四大組件，因此也必須在AndroidMainfest.xml中完成對ContentProvider的注冊。注冊方式為：
?
與ContentProvider相關(guān)操作的類介紹
從Uri談起
什么是Uri?
Uri是指通用資源標(biāo)志符
A：前綴表明數(shù)據(jù)受控于一個內(nèi)容提供者。它從不修改，也就是schema
B：是指在AndroidMainfest.xml中我們注冊的provider中的android:authorities屬性所對應(yīng)的
C：具體操作于哪個條目
D：具體指定到哪個條目下的哪條記錄
再看它的類結(jié)構(gòu)和常用方法：
Uri
在這個里它是沒有構(gòu)造方法的，它通常通過下面的這個方法來返回一個Uri對象
方法名稱 | 描述 |
public static Uri parse (String uriString) | 通過一個傳入的字符串來構(gòu)造一個Uri對象 |
熟悉完Uri類再看與之相關(guān)的另外兩個類
UriMatcher類：
因?yàn)閁ri代表了要操作的數(shù)據(jù)，所以我們經(jīng)常需要解析Uri，并從Uri中獲取數(shù)據(jù)。Android系統(tǒng)提供了兩個用于操作Uri的工具類，分別為UriMatcher 和ContentUris 。掌握它們的使用，會便于我們的開發(fā)工作。
先看下它比較常用的幾個方法：
方法名稱 | 描述 |
public void addURI (String authority, String path, int code) | 往UriMatcher類里添加一個拼湊的Uri，在此我們可以理解為UriMatcher為一個Uri的容器，為個容器里面包含著我們即將可能要操作的Ｕri，它用于我們業(yè)務(wù)邏輯的處理，特別是第三個參數(shù)code，如果通過下面的match()方法匹配成功就返回這個code值 |
public int match (Uri uri) | 與傳入的Uri匹配，它會首先與找我們之前通過addURI方法添加進(jìn)來的Uri匹配，如果匹配成功就返回之前我們設(shè)置的code值，否則返回一個UriMatcher.NO_MATCH常量值為-1 |
熟悉完上面的方法，那么我們再來看它如何使用：
UriMatcher類用于匹配Uri，它的用法如下：
UriMatcher類的用法
首先第一步把你需要匹配Uri路徑全部給注冊上，如下：
//常量UriMatcher.NO_MATCH表示不匹配任何路徑的返回碼
UriMatcher? sMatcher = new UriMatcher(UriMatcher.NO_MATCH);
//如果match()方法匹配content:// com.jiahui.provider.myprovider/person路徑，返回匹配碼為1
sMatcher.addURI(“com.jiahui.provider.myprovider”, “person”, 1);//添加需要匹配uri，如果匹配就會返回匹配碼
//如果match()方法匹配content:// com.jiahui.provider.myprovider /person/230路徑，返回匹配碼為2
sMatcher.addURI(“com.jiahui.provider.myprovider”, “person/#”, 2);//#號為通配符
switch (sMatcher.match(Uri.parse("content:// com.jiahui.provider.myprovider /person/10"))) {
?? case 1
??? break;
?? case 2
??? break;
?? default://不匹配
??? break;
}
注冊完需要匹配的Uri后，就可以使用sMatcher.match(uri)方法對輸入的Uri進(jìn)行匹配，如果匹配就返回匹配碼，匹配碼是調(diào)用addURI()方法傳入的第三個參數(shù)，假設(shè)匹配content://cn.itcast.provider.personprovider/person路徑，返回的匹配碼為1
再看另外一個工具類
ContentUris：
它用于在Uri后面追加一個ID或者解析出傳入的Uri所帶上的ID值，常用的兩個方法如下：
方法名稱 | 描述 |
public static Uri withAppendedId (Uri contentUri, long id) | 用于為路徑加上ID部分 |
public static long parseId (Uri contentUri) | 從路徑中獲取ID部分 |
熟悉完上面所提及的相關(guān)的類，接下來我們再看這個ContentProvider核心類
ContentProvider
常用方法
方法名稱 | 描述 |
public abstract boolean onCreate () | 在ContentProvider創(chuàng)建后被調(diào)用。 |
public abstract Uri insert (Uri uri, ContentValues values) | 根據(jù)Uri插入values對就的數(shù)據(jù) |
public abstract int delete (Uri uri, String selection, String[] selectionArgs) | 根據(jù)Uri刪除selection指定的條件所匹配的全部記錄 |
public abstract int update (Uri uri, ContentValues values, String selection, String[] selectionArgs) | 根據(jù)Uri修改selection指定的條件所匹配的全部記錄 |
public abstract Cursor query (Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) | 根據(jù)Uri查詢出selection指定的條件所匹配的全部記錄，并且可以指定查詢哪些列（projection），以什么方式（sortOrder）排序 |
public abstract String getType (Uri uri) | 返回當(dāng)前Uri所數(shù)據(jù)的MIME類型，如果該Uri對應(yīng)的數(shù)據(jù)可能包括多條記錄，那么MIME類型字符串就是以vnd.android.cursor.dir/開頭,如果Uri對應(yīng)的數(shù)據(jù)只包含一條記錄，那么MIME類型字符串就是以vnd.android.cursor.item/開頭 |
既然我們知道了ContentProvider類是向外提供數(shù)據(jù)的一種機(jī)制，那么在之前我們也說過要想來操作這個對外提供的數(shù)據(jù)，我們就用到了另外一個類：
ContentResolver
在這個類里面也定義了一系列的增、刪、改、查方法，與其ContentProvider定義的方法基本上相同，在此不再復(fù)核。讀者可以自己查閱相關(guān)文檔。
可能大家在這里還是有點(diǎn)理不清這些類的一些關(guān)系，特別是ContentResolver與ContentProvider與Uri類的關(guān)系，那么我上張圖吧，或許對大家有所幫助：
好了熟悉完上面所述的這么多類那么我們就在實(shí)踐中見證真理吧：
實(shí)例：
實(shí)現(xiàn)效果：
??
代碼實(shí)現(xiàn)：
?
先開發(fā)我們自己的ContentProvider:
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package?com.jiahui.provider;????import?com.jiahui.db.DBHelper;????import?android.content.ContentProvider;??import?android.content.ContentUris;??import?android.content.ContentValues;??import?android.content.UriMatcher;??import?android.database.Cursor;??import?android.database.sqlite.SQLiteDatabase;??import?android.net.Uri;????public?class?MyProvider?extends?ContentProvider?{????????private?DBHelper?dbHelper;??????//?定義一個UriMatcher類??????private?static?final?UriMatcher?MATCHER?=?new?UriMatcher(??????????????UriMatcher.NO_MATCH);??????private?static?final?int?PERSONS?=?1;??????private?static?final?int?PERSON?=?2;??????static?{??????????MATCHER.addURI("com.jiahui.provider.myprovider",?"person",?PERSONS);??????????MATCHER.addURI("com.jiahui.provider.myprovider",?"person/#",?PERSON);????????}??????@Override??????public?boolean?onCreate()?{??????????System.out.println("---oncreate----");??????????dbHelper?=?new?DBHelper(this.getContext());??????????return?false;??????}????????//?查詢數(shù)據(jù)??????@Override??????public?Cursor?query(Uri?uri,?String[]?projection,?String?selection,??????????????String[]?selectionArgs,?String?sortOrder)?{????????????SQLiteDatabase?db?=?dbHelper.getWritableDatabase();??????????switch?(MATCHER.match(uri))?{??????????case?PERSONS:??????????????//?查詢所有的數(shù)據(jù)??????????????return?db.query("person",?projection,?selection,?selectionArgs,??????????????????????null,?null,?sortOrder);????????????case?PERSON:??????????????//?查詢某個ID的數(shù)據(jù)??????????????//?通過ContentUris這個工具類解釋出ID??????????????long?id?=?ContentUris.parseId(uri);??????????????String?where?=?"?_id="?+?id;??????????????if?(!"".equals(selection)?&&?selection?!=?null)?{??????????????????where?=?selection?+?"?and?"?+?where;????????????????}????????????????return?db.query("person",?projection,?where,?selectionArgs,?null,??????????????????????null,?sortOrder);??????????default:????????????????throw?new?IllegalArgumentException("unknow?uri"?+?uri.toString());??????????}????????}????????//?返回當(dāng)前操作的數(shù)據(jù)的mimeType??????@Override??????public?String?getType(Uri?uri)?{??????????switch?(MATCHER.match(uri))?{??????????case?PERSONS:??????????????return?"vnd.android.cursor.dir/person";??????????case?PERSON:??????????????return?"vnd.android.cursor.item/person";??????????default:??????????????throw?new?IllegalArgumentException("Unkwon?Uri:"?+?uri.toString());??????????}??????}????????//?插入數(shù)據(jù)??????@Override??????public?Uri?insert(Uri?uri,?ContentValues?values)?{??????????SQLiteDatabase?db?=?dbHelper.getWritableDatabase();??????????Uri?insertUri?=?null;??????????switch?(MATCHER.match(uri))?{??????????case?PERSONS:????????????????long?rowid?=?db.insert("person",?"name",?values);??????????????insertUri?=?ContentUris.withAppendedId(uri,?rowid);????????????????break;????????????default:??????????????throw?new?IllegalArgumentException("Unkwon?Uri:"?+?uri.toString());??????????}??????????return?insertUri;??????}????????//?刪除數(shù)據(jù)??????@Override??????public?int?delete(Uri?uri,?String?selection,?String[]?selectionArgs)?{??????????SQLiteDatabase?db?=?dbHelper.getWritableDatabase();??????????int?count?=?0;??????????switch?(MATCHER.match(uri))?{??????????case?PERSONS:??????????????count?=?db.delete("person",?selection,?selectionArgs);??????????????return?count;????????????case?PERSON:??????????????long?id?=?ContentUris.parseId(uri);??????????????String?where?=?"_id="?+?id;??????????????if?(selection?!=?null?&&?!"".equals(selection))?{??????????????????where?=?selection?+?"?and?"?+?where;??????????????}??????????????count?=?db.delete("person",?where,?selectionArgs);??????????????return?count;????????????default:??????????????throw?new?IllegalArgumentException("Unkwon?Uri:"?+?uri.toString());??????????}??????}????????//?更新數(shù)據(jù)??????@Override??????public?int?update(Uri?uri,?ContentValues?values,?String?selection,??????????????String[]?selectionArgs)?{????????????SQLiteDatabase?db?=?dbHelper.getWritableDatabase();????????????int?count?=?0;??????????switch?(MATCHER.match(uri))?{??????????case?PERSONS:??????????????count?=?db.update("person",?values,?selection,?selectionArgs);??????????????break;??????????case?PERSON:??????????????//?通過ContentUri工具類得到ID??????????????long?id?=?ContentUris.parseId(uri);??????????????String?where?=?"_id="?+?id;??????????????if?(selection?!=?null?&&?!"".equals(selection))?{??????????????????where?=?selection?+?"?and?"?+?where;??????????????}??????????????count?=?db.update("person",?values,?where,?selectionArgs);??????????????break;??????????default:??????????????throw?new?IllegalArgumentException("Unkwon?Uri:"?+?uri.toString());??????????}??????????return?count;??????}????}??
?
千萬別忘記了要在AndroidMainfest.xml文件中注冊這個組件哦：
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<provider?????????????android:authorities="com.jiahui.provider.myprovider"?????????????android:name=".MyProvider"?>?????????</provider>??
?
然后在一個主Activity編寫一些實(shí)現(xiàn)代碼：
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package?com.jiahui.provider;????import?java.util.ArrayList;??import?java.util.HashMap;??import?java.util.List;??import?java.util.Map;????import?android.app.Activity;??import?android.content.ContentResolver;??import?android.content.ContentUris;??import?android.content.ContentValues;??import?android.content.Context;??import?android.content.Intent;??import?android.database.Cursor;??import?android.net.Uri;??import?android.os.Bundle;??import?android.os.Handler;??import?android.os.Message;??import?android.view.View;??import?android.widget.AdapterView;??import?android.widget.AdapterView.OnItemClickListener;??import?android.widget.Button;??import?android.widget.EditText;??import?android.widget.ListView;??import?android.widget.SimpleAdapter;??import?android.widget.Toast;????import?com.jiahui.model.Person;????public?class?ContentProviderDemoActivity?extends?Activity?{????????private?Button?btnadd,?btnqueryall;??????private?EditText?edtname,?edtage;????????private?ListView?lvall;????????private?List<Person>?persons;??private?SimpleAdapter?simpleAdapter;??????private?Handler?handler?=?new?Handler()?{????????????@Override??????????public?void?handleMessage(Message?msg)?{????????????????List<Map<String,?Object>>?data?=?(List<Map<String,?Object>>)?msg.obj;????????????????System.out.println(data.size());??????????????????????????????simpleAdapter?=?new?SimpleAdapter(??????????????????????ContentProviderDemoActivity.this,?data,?R.layout.list_item,??????????????????????new?String[]?{?"id",?"name",?"age"?},?new?int[]?{??????????????????????????????R.id.tvId,?R.id.tvname,?R.id.tvage?});????????????????????????lvall.setAdapter(simpleAdapter);????????????????????????}????????};????????public?void?onCreate(Bundle?savedInstanceState)?{??????????super.onCreate(savedInstanceState);??????????setContentView(R.layout.main);????????????persons?=?new?ArrayList<Person>();????????????btnqueryall?=?(Button)?this.findViewById(R.id.btnqueryall);??????????btnadd?=?(Button)?this.findViewById(R.id.btnadd);??????????edtname?=?(EditText)?this.findViewById(R.id.edtname);??????????edtage?=?(EditText)?this.findViewById(R.id.edtage);??????????lvall?=?(ListView)?this.findViewById(R.id.lvall);????????????btnadd.setOnClickListener(new?View.OnClickListener()?{????????????????@Override??????????????public?void?onClick(View?v)?{??????????????????ContentResolver?contentResolver?=?ContentProviderDemoActivity.this??????????????????????????.getContentResolver();????????????????????Uri?url?=?Uri??????????????????????????.parse("content://com.jiahui.provider.myprovider/person");??????????????????ContentValues?values?=?new?ContentValues();??????????????????values.put("name",?edtname.getText().toString());??????????????????values.put("age",?edtage.getText().toString());??????????????????Uri?result?=?contentResolver.insert(url,?values);????????????????????System.out.println(result.toString());????????????????????????????????????if?(ContentUris.parseId(result)>0)?{??????????????????????Toast.makeText(ContentProviderDemoActivity.this,?"添加成功",?Toast.LENGTH_LONG).show();??????????????????????//添加成功后再啟動線程查詢??????????????????????MyThread?thread?=?new?MyThread(ContentProviderDemoActivity.this);??????????????????????thread.start();??????????????????}??????????????}??????????});??????????//查詢所有??????????btnqueryall.setOnClickListener(new?View.OnClickListener()?{????????????????@Override??????????????public?void?onClick(View?v)?{????????????????????????????????MyThread?thread?=?new?MyThread(ContentProviderDemoActivity.this);??????????????????thread.start();??????????????}??????????});????????????lvall.setOnItemClickListener(new?OnItemClickListener()?{????????????????@Override??????????????public?void?onItemClick(AdapterView<?>?parent,?View?view,??????????????????????int?position,?long?id)?{??????????????????//?Toast.makeText(ContentProviderDemoActivity.this,?position,??????????????????//?Toast.LENGTH_LONG).show();??????????????????System.out.println("position:"?+?position);????????????????????Person?person?=?persons.get(position);??????????????????Bundle?bundle?=?new?Bundle();??????????????????bundle.putInt("id",?person.getId());????????????????????bundle.putString("name",?person.getName());????????????????????bundle.putInt("age",?person.getAge());????????????????????Intent?intent?=?new?Intent(ContentProviderDemoActivity.this,??????????????????????????ItemActivity.class);??????????????????intent.putExtra("item",?bundle);??????????????????startActivityForResult(intent,?1);????????????????}??????????});????????}????????????@Override??????protected?void?onActivityResult(int?requestCode,?int?resultCode,?Intent?data)?{????????????if?(resultCode==2)?{??????????????MyThread?thread?=?new?MyThread(ContentProviderDemoActivity.this);??????????????thread.start();????????????}????????????????????}??????????class?MyThread?extends?Thread?{????????????Context?context;????????????public?MyThread(Context?context)?{??????????????//一定要清空。否則會?有問題，每執(zhí)行一次都會把之前的全部的item加進(jìn)去??????????????persons.clear();??????????????lvall.setAdapter(null);????????????????????????????this.context?=?context;??????????}????????????@Override??????????public?void?run()?{????????????????Uri?url?=?Uri??????????????????????.parse("content://com.jiahui.provider.myprovider/person");????????????????Cursor?cursor?=?context.getContentResolver().query(url,??????????????????????new?String[]?{?"_id",?"name",?"age"?},?null,?null,?"_id");????????????????while?(cursor.moveToNext())?{????????????????????//?System.out.println("_id:"??????????????????//?+?cursor.getInt(cursor.getColumnIndex("_id")));??????????????????//?System.out.println("name:"??????????????????//?+?cursor.getString(cursor.getColumnIndex("name")));??????????????????//?System.out.println("age:"??????????????????//?+?cursor.getInt(cursor.getColumnIndex("age")));??????????????????Person?person?=?new?Person();??????????????????person.setId(cursor.getInt(cursor.getColumnIndex("_id")));??????????????????person.setName(cursor.getString(cursor.getColumnIndex("name")));??????????????????person.setAge(cursor.getInt(cursor.getColumnIndex("age")));??????????????????persons.add(person);????????????????????????????}????????????????cursor.close();????????????????????????????List<Map<String,?Object>>?data?=?new?ArrayList<Map<String,?Object>>();????????????????Map<String,?Object>?map=null;??????????????for?(int?i?=?0;?i?<?persons.size();?i++)?{????????????????????map?=?new?HashMap<String,?Object>();????????????????????map.put("id",?persons.get(i).getId());??????????????????map.put("name",?persons.get(i).getName());????????????????????map.put("age",?persons.get(i).getAge());??????????????????data.add(map);????????????????}??????????????if?(data.size()>=persons.size())?{????????????????????????????????}??????????????Message?msg?=?handler.obtainMessage();??????????????msg.obj?=?data;??????????????handler.sendMessage(msg);??????????}????????}????}??
?
ItemActivity代碼：
[java] view plain copy print ? <EMBED id=ZeroClipboardMovie_4 name=ZeroClipboardMovie_4 type=application/x-shockwave-flash align=middle pluginspage=http://www.macromedia.com/go/getflashplayer height=16 width=32 src=http://static.blog.csdn.net/scripts/ZeroClipboard/ZeroClipboard.swf wmode="transparent" flashvars="id=4&width=32&height=16" allowfullscreen="false" allowscriptaccess="always" bgcolor="#ffffff" quality="best" menu="false" loop="false">
package?com.jiahui.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.Button;??import?android.widget.EditText;??import?android.widget.TextView;??import?android.widget.Toast;????public?class?ItemActivity?extends?Activity?{????????private?EditText?edt_item_name;??????private?EditText?edt_item_age;??????private?EditText?edt_item_id;??????private?Button?btndel,?btnupdate;????????private?Intent?intent;????????@Override??????protected?void?onCreate(Bundle?savedInstanceState)?{??????????//?TODO?Auto-generated?method?stub??????????super.onCreate(savedInstanceState);????????????setContentView(R.layout.item);????????????edt_item_id?=?(EditText)?this.findViewById(R.id.edt_item_id);??????????edt_item_id.setEnabled(false);//?控制不可用??????????edt_item_name?=?(EditText)?this.findViewById(R.id.edt_item_name);??????????edt_item_age?=?(EditText)?this.findViewById(R.id.edt_item_age);??????????//?得到傳過來的數(shù)據(jù)??????????btndel?=?(Button)?this.findViewById(R.id.btndel);??????????btnupdate?=?(Button)?this.findViewById(R.id.btnupdate);????????????intent?=?getIntent();????????????Bundle?bundle?=?intent.getBundleExtra("item");????????????int?id?=?bundle.getInt("id");??????????System.out.println("id----"?+?id);??????????String?name?=?bundle.getString("name");??????????int?age?=?bundle.getInt("age");????????????edt_item_id.setText(String.valueOf(id));??????????edt_item_name.setText(name);??????????edt_item_age.setText(String.valueOf(age));????????????btndel.setOnClickListener(new?View.OnClickListener()?{????????????????@Override??????????????public?void?onClick(View?v)?{??????????????????ContentResolver?contentResolver?=?ItemActivity.this??????????????????????????.getContentResolver();??????????????????//?構(gòu)建Uri??????????????????String?url?=?"content://com.jiahui.provider.myprovider/person/"??????????????????????????+?edt_item_id.getText();??????????????????Uri?uri?=?Uri.parse(url);????????????????????int?result?=?contentResolver.delete(uri,?null,?null);??????????????????System.out.println("delete?result:"?+?result);????????????????????if?(result?>=?1)?{??????????????????????Toast.makeText(ItemActivity.this,?"刪除成功",?Toast.LENGTH_LONG)??????????????????????????????.show();??????????????????????ItemActivity.this.setResult(2);??????????????????????ItemActivity.this.finish();??????????????????}????????????????}??????????});????????????btnupdate.setOnClickListener(new?View.OnClickListener()?{????????????????@Override??????????????public?void?onClick(View?v)?{????????????????????ContentResolver?contentResolver?=?ItemActivity.this??????????????????????????.getContentResolver();??????????????????//?構(gòu)建Uri??????????????????String?url?=?"content://com.jiahui.provider.myprovider/person/"??????????????????????????+?edt_item_id.getText();??????????????????Uri?uri?=?Uri.parse(url);??????????????????ContentValues?values?=?new?ContentValues();??????????????????values.put("name",?edt_item_name.getText().toString());??????????????????values.put("age",??????????????????????????Integer.parseInt(edt_item_age.getText().toString()));??????????????????int?result?=?contentResolver.update(uri,?values,?null,?null);??????????????????System.out.println("update?result:"?+?result);??????????????????if?(result?>=?1)?{??????????????????????Toast.makeText(ItemActivity.this,?"更新成功",?Toast.LENGTH_LONG)??????????????????????????????.show();??????????????????????ItemActivity.this.setResult(2);??????????????????????ItemActivity.this.finish();??????????????????}????????????????}??????????});????????}????}??
特別說明：這個例子也是與之前講過的一講與SQLite知識相關(guān)的代碼中一個類，讀者需要用到之前的DBHelper類，請自行拷貝。
轉(zhuǎn)載于:https://my.oschina.net/u/1463230/blog/269212
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