使用ContentProvider

转载请注明出处： http://blog.csdn.net/a992036795/article/details/51610936

一、简介：
ContentProvider 在android中的作用是对外共享数据，也就是说可以通过ContentProvider把应用中的数据共享给其他应用访问，其他应用可以通过ContentProvider对应用中的数据进行增、删、该、查。使用ContentProvider的好处是，统一了数据的访问方式。
ContentProvider的体层实现实际是Binder。

二、使用：
一般ContentProvider的实现都是对SqliteOpenHelp的进一步包装，通过Uri映射来判断选择需要操作数据库中的那个表，并且进行增、删、改、查处理。

我们先来看以一下ContentProvider的定义：

** * Content providers are one of the primary building blocks of Android applications, providing * content to applications. They encapsulate data and provide it to applications through the single * {@link ContentResolver} interface. A content provider is only required if you need to share * data between multiple applications. For example, the contacts data is used by multiple * applications and must be stored in a content provider. If you don't need to share data amongst * multiple applications you can use a database directly via * {@link android.database.sqlite.SQLiteDatabase}. * * When a request is made via * a {@link ContentResolver} the system inspects the authority of the given URI and passes the * request to the content provider registered with the authority. The content provider can interpret * the rest of the URI however it wants. The {@link UriMatcher} class is helpful for parsing * URIs.
 * * The primary methods that need to be implemented are: * 
 *   {@link #onCreate} which is called to initialize the provider
 *   {@link #query} which returns data to the caller
 *   {@link #insert} which inserts new data into the content provider
 *   {@link #update} which updates existing data in the content provider
 *   {@link #delete} which deletes data from the content provider
 *   {@link #getType} which returns the MIME type of data in the content provider
 * 
 * * class="caution">Data access methods (such as {@link #insert} and * {@link #update}) may be called from many threads at once, and must be thread-safe. * Other methods (such as {@link #onCreate}) are only called from the application * main thread, and must avoid performing lengthy operations.  See the method * descriptions for their expected thread behavior.
 * * Requests to {@link ContentResolver} are automatically forwarded to the appropriate * ContentProvider instance, so subclasses don't have to worry about the details of * cross-process calls.
 * * <div class="special reference"> * Developer Guides
 * For more information about using content providers, read the * "{@docRoot}guide/topics/providers/content-providers.html">Content Providers * developer guide.
 */public abstract class ContentProvider implements ComponentCallbacks2 {    private static final String TAG = "ContentProvider";

通过注释我们大概可以了解到：
我们自定义一个ContentProvider，需要实现它的onCreate、query、insert、update、delete、getType方法。
因为它底层实现是Binder、其实对源码进行分析的话、可以看到如果是夸进程调用的话，OnCreate将发生在主线程、而其他方法将发生在Binder线程池中。
这一点，我们可以通过在方法打印进程名会得到证实。

06-08 01:46:21.903 3016-3016/com.blueberry.process1 I/SimpleContentProvider: onCreate: current thread: main06-08 01:46:21.920 3016-3032/com.blueberry.process1 I/SimpleContentProvider: insert: current thread: Binder_206-08 01:46:22.968 3016-3032/com.blueberry.process1 I/SimpleContentProvider: query: current thread: Binder_2

这是我写的一个例子的测试结果。下面我们将自己写一个ContentProvider。
首先我们先定义个SQLiteOpenHelp，来创建1个数据库，其中存在2张表。
下面给出类的定义：

/** * Created by blueberry on 2016/6/7. */public class UserInfoDbHelper extends SQLiteOpenHelper {    private static final String TAG = "UserInfoDbHelper";    private static final String DB_NAME = "userinfo.db"; /*数据库名*/    private static final int DB_VERSION = 1;/*版本号*/    public static final String TABLE_USER_INFO = "userinfo";/*用户信息表*/    public static final String TABLE_COMPANY = "company";/*公司表*/    public static final String TEL_COLUMN = "tel_num";/*电话号码*/    public static final String DESC_COLUMN = "desc";/*描述*/    public static final String COMP_ID_COLUMN = "comp_id";/*公司id*/    public static final String ID_COLUMN = "id";/*公司的id*/    public static final String BUSINESS_COLUMN = "business";/*公司的业务*/    public static final String ADDR_COLUMN = "addr";/*公司位置*/    //  表 userinfo    //  | 字段名            | 类型          |意义             |    //  | Tel_num           | TEXT         |电话号码          |    //  | Desc              | TEXT         |描述              |    //  | comp_id           | INTEGER      | 公司id           |    //    //  表 company    //  |字段名              |类型           |意义             |    //  |Id                 |INTEGER        |公司的id          |    //  |Business           | TEXT          |公司的业务        |    //  | Addr              | TEXT          | 公司位置         |    private static final String POSTCODE_TABLE_SQL ="CREATE TABLE IF NOT EXISTS "+TABLE_USER_INFO +" ("            +TEL_COLUMN+" TEXT ,"            +COMP_ID_COLUMN+" INTEGER ,"            +DESC_COLUMN+" TEXT"            +")" ;    private static final String COMPANY_TABLE_SQL ="CREATE TABLE IF NOT EXISTS "+TABLE_COMPANY+" ("            +ID_COLUMN +" INTEGER PRIMEARY KEY ,"            +BUSINESS_COLUMN+" TEXT ,"            +ADDR_COLUMN+" TEXT" +")" ;    public UserInfoDbHelper(Context context) {        super(context, DB_NAME , null, DB_VERSION);    }    @Override    public void onCreate(SQLiteDatabase db) {        db.execSQL(POSTCODE_TABLE_SQL);        db.execSQL(COMPANY_TABLE_SQL);    }    @Override    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {    }}

可以看到创建了2张表，一张为userinfo 一张为 company。字段名已在注释列出。

下面继续给出自定一ContentProvider的定义：

/** * Created by blueberry on 2016/6/7. */public class SimpleContentProvider extends ContentProvider {    private static final String TAG = "SimpleContentProvider";    public static final String AUTHORITY = "com.blueberry.test08.provider";    /*该ContentProvider返回的数据类型定义，数据集合*/    private static final String CONTENT_TYPE ="vnd.android.cursor.dir/vnd."+AUTHORITY;    /*单项数据*/    private static final String CONTNET_TYPE_ITEM ="vnd.android.cursor.item/vnd."+AUTHORITY ;    public static final Uri USERINFO_CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/"            + UserInfoDbHelper.TABLE_USER_INFO);    public static final Uri COMPANY_CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/"            + UserInfoDbHelper.TABLE_COMPANY);    public static final int USERINFO_CODE = 0;    public static final int USERINFO_ITEM_CODE = 1;    public static final int COMPANY_CODE = 2;    public static final int COMPANY_ITEM_CODE = 3;    private static final UriMatcher sUriMatcher = new UriMatcher(UriMatcher.NO_MATCH);    static {        /**         * 这里使用2种通配符 "*"表示匹配任意长度的任意字符，"#"表示匹配任意长度的数字         * 因此，content://com.blueberry.test08.provider/company 表示查询company表中的所有数据         * 而 conent://com.blueberry.test08.provider/company/# 表示根据一个数字id 查询一条信息         */        sUriMatcher.addURI(AUTHORITY, "userinfo", USERINFO_CODE);        sUriMatcher.addURI(AUTHORITY, "userinfo/*", USERINFO_ITEM_CODE);        sUriMatcher.addURI(AUTHORITY, "company", COMPANY_CODE);        sUriMatcher.addURI(AUTHORITY, "company/#", COMPANY_ITEM_CODE);    }    private SQLiteDatabase mDatabase;    /**     * 夸进程时发生在主线程     *     * @return     */    @Override    public boolean onCreate() {        Log.i(TAG, "onCreate: current thread: " + Thread.currentThread().getName());        /*返回一个可读写的数据库*/        mDatabase = new UserInfoDbHelper(getContext()).getWritableDatabase();        return true;    }    /**     * 夸进程时发生在工作线程     *     * @param uri     * @param projection     * @param selection     * @param selectionArgs     * @param sortOrder     * @return     */    @Nullable    @Override    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {        Log.i(TAG, "query: current thread: " + Thread.currentThread().getName());        Cursor cursor = null;        switch (sUriMatcher.match(uri)) {            case USERINFO_CODE:                cursor = mDatabase.query(UserInfoDbHelper.TABLE_USER_INFO, projection, selection, selectionArgs, null, null, sortOrder);                break;            case USERINFO_ITEM_CODE:                String tel = uri.getPathSegments().get(1);                cursor = mDatabase.query(UserInfoDbHelper.TABLE_USER_INFO, projection, "tel_num = ?", new String[]{tel}, null, null, sortOrder);                break;            case COMPANY_CODE:                cursor = mDatabase.query(UserInfoDbHelper.TABLE_COMPANY, projection, selection, selectionArgs, null, null, sortOrder);                break;            case COMPANY_ITEM_CODE:                String cid = uri.getPathSegments().get(1);                cursor = mDatabase.query(UserInfoDbHelper.TABLE_COMPANY, projection, "id = ?", new String[]{cid}, null, null, sortOrder);                break;        }        return cursor;    }    /**     * 夸进程时发生在工作线程     *     * @param uri     * @param values     * @return     */    @Nullable    @Override    public Uri insert(Uri uri, ContentValues values) {        Log.i(TAG, "insert: current thread: " + Thread.currentThread().getName());        long newId = 0;        Uri newUri = null;        switch (sUriMatcher.match(uri)) {            case USERINFO_CODE:                newId = mDatabase.insert(UserInfoDbHelper.TABLE_USER_INFO, null, values);                newUri = Uri.parse("content://" + AUTHORITY + "/" + UserInfoDbHelper.TABLE_USER_INFO + "/" + newId);                break;            case COMPANY_CODE:                newId = mDatabase.insert(UserInfoDbHelper.TABLE_COMPANY, null, values);                newUri = Uri.parse("content://" + AUTHORITY + "/" + UserInfoDbHelper.TABLE_COMPANY + "/" + newId);                break;        }        if (newId > 0) return newUri;        throw new IllegalArgumentException("Failed to insert row info" + uri);    }    /**     * 夸进程时发生在工作线程     *     * @param uri     * @return     */    @Nullable    @Override    public String getType(Uri uri) {        Log.i(TAG, "getType: current thread: " + Thread.currentThread().getName());        switch (sUriMatcher.match(uri)){            case USERINFO_CODE:            case COMPANY_CODE:                return CONTENT_TYPE;            case USERINFO_ITEM_CODE:            case COMPANY_ITEM_CODE:                return CONTNET_TYPE_ITEM;            default:                throw new RuntimeException("错误的 uri");        }    }    @Nullable    @Override    public Bundle call(String method, String arg, Bundle extras) {        return super.call(method, arg, extras);    }    /**     * 夸进程时发生在工作线程     *     * @param uri     * @param selection     * @param selectionArgs     * @return     */    @Override    public int delete(Uri uri, String selection, String[] selectionArgs) {        Log.i(TAG, "delete: current thread: " + Thread.currentThread().getName());        return 0;    }    /**     * 夸进程时发生在工作线程     *     * @param uri     * @param values     * @param selection     * @param selectionArgs     * @return     */    @Override    public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {        Log.i(TAG, "update: current thread: " + Thread.currentThread().getName());        return 0;    }}

我这里只是测试，所以只实现了query和inser方法。这里主要用了一个 UriMatcher类。

这里对上面的程序简要分析一下：
我们先来简要看一下Uri,Uri代表了要操作的数据表的绝对路径，Uri主要包含两部分信息，一是需要操作的ContentProvider，二是对ContentProvider中的哪个表进行操作。一个Uri的组成为：

ContentProvider的Schema已经由Android固定设置为content://, Authority用于唯一标示这个ContentProvider，外部调用者可以根据这个标示来找到它，这里的path就是要查询的数据表，最后的id是可选字段，例如，我们操作特定的数据项时就会指定一个查询条件，如果所有联系人的uri为 content://contacts/people,某个联系人的Uri:content://contacts/people/5,这个5 就是联系人的id，也就对应了查询的关键字。

这里我们的Authority为 com.blueberry.test08.provider。

接下来我们看以UriMatcher
我们来看一下这个类的定义：

/**Utility class to aid in matching URIs in content providers.To use this class, build up a tree of UriMatcher objects.For example:
    private static final int PEOPLE = 1;    private static final int PEOPLE_ID = 2;    private static final int PEOPLE_PHONES = 3;    private static final int PEOPLE_PHONES_ID = 4;    private static final int PEOPLE_CONTACTMETHODS = 7;    private static final int PEOPLE_CONTACTMETHODS_ID = 8;    private static final int DELETED_PEOPLE = 20;    private static final int PHONES = 9;    private static final int PHONES_ID = 10;    private static final int PHONES_FILTER = 14;    private static final int CONTACTMETHODS = 18;    private static final int CONTACTMETHODS_ID = 19;    private static final int CALLS = 11;    private static final int CALLS_ID = 12;    private static final int CALLS_FILTER = 15;    private static final UriMatcher sURIMatcher = new UriMatcher(UriMatcher.NO_MATCH);    static    {        sURIMatcher.addURI("contacts", "people", PEOPLE);        sURIMatcher.addURI("contacts", "people/#", PEOPLE_ID);        sURIMatcher.addURI("contacts", "people/#/phones", PEOPLE_PHONES);        sURIMatcher.addURI("contacts", "people/#/phones/#", PEOPLE_PHONES_ID);        sURIMatcher.addURI("contacts", "people/#/contact_methods", PEOPLE_CONTACTMETHODS);        sURIMatcher.addURI("contacts", "people/#/contact_methods/#", PEOPLE_CONTACTMETHODS_ID);        sURIMatcher.addURI("contacts", "deleted_people", DELETED_PEOPLE);        sURIMatcher.addURI("contacts", "phones", PHONES);        sURIMatcher.addURI("contacts", "phones/filter/*", PHONES_FILTER);        sURIMatcher.addURI("contacts", "phones/#", PHONES_ID);        sURIMatcher.addURI("contacts", "contact_methods", CONTACTMETHODS);        sURIMatcher.addURI("contacts", "contact_methods/#", CONTACTMETHODS_ID);        sURIMatcher.addURI("call_log", "calls", CALLS);        sURIMatcher.addURI("call_log", "calls/filter/*", CALLS_FILTER);        sURIMatcher.addURI("call_log", "calls/#", CALLS_ID);    }
Starting from API level {@link android.os.Build.VERSION_CODES#JELLY_BEAN_MR2}, paths can start with a leading slash.  For example:
        sURIMatcher.addURI("contacts", "/people", PEOPLE);
Then when you need to match against a URI, call {@link #match}, providingthe URL that you have been given.  You can use the result to build a query,return a type, insert or delete a row, or whatever you need, without duplicatingall of the if-else logic that you would otherwise need.  For example:
    public String getType(Uri url)    {        int match = sURIMatcher.match(url);        switch (match)        {            case PEOPLE:                return "vnd.android.cursor.dir/person";            case PEOPLE_ID:                return "vnd.android.cursor.item/person";... snip ...                return "vnd.android.cursor.dir/snail-mail";            case PEOPLE_ADDRESS_ID:                return "vnd.android.cursor.item/snail-mail";            default:                return null;        }    }
instead of:    public String getType(Uri url)    {        List pathSegments = url.getPathSegments();        if (pathSegments.size() >= 2) {            if ("people".equals(pathSegments.get(1))) {                if (pathSegments.size() == 2) {                    return "vnd.android.cursor.dir/person";                } else if (pathSegments.size() == 3) {                    return "vnd.android.cursor.item/person";... snip ...                    return "vnd.android.cursor.dir/snail-mail";                } else if (pathSegments.size() == 3) {                    return "vnd.android.cursor.item/snail-mail";                }            }        }        return null;    }
*/public class UriMatcher{

可以看到，注释中已经把他的用法说的查不到了。
UriMather 会根据uri来匹配出对应的 code来使得我们判断该查询那张表，

这里我们定义了四个 code. 分别对用与用户信息查询、单个用户信息查询、公司查询、单个公司查询。

 public static final int USERINFO_CODE = 0;    public static final int USERINFO_ITEM_CODE = 1;    public static final int COMPANY_CODE = 2;    public static final int COMPANY_ITEM_CODE = 3;

我们通过如下方法将对应信息添加进去:

    static {        /**         * 这里使用2种通配符 "*"表示匹配任意长度的任意字符，"#"表示匹配任意长度的数字         * 因此，content://com.blueberry.test08.provider/company 表示查询company表中的所有数据         * 而 conent://com.blueberry.test08.provider/company/# 表示根据一个数字id 查询一条信息         */        sUriMatcher.addURI(AUTHORITY, "userinfo", USERINFO_CODE);        sUriMatcher.addURI(AUTHORITY, "userinfo/*", USERINFO_ITEM_CODE);        sUriMatcher.addURI(AUTHORITY, "company", COMPANY_CODE);        sUriMatcher.addURI(AUTHORITY, "company/#", COMPANY_ITEM_CODE);    }

我们接着来看一下getType方法，根据UriMather推荐的方法，如果查询的是数据集合，我们返回的类型应该是 vnd.android.cursor.dir/….. 如果是查询单个数据我们返回的类型应该是 vnd.android.cursor.item/….

  /*该ContentProvider返回的数据类型定义，数据集合*/    private static final String CONTENT_TYPE ="vnd.android.cursor.dir/vnd."+AUTHORITY;    /*单项数据*/    private static final String CONTNET_TYPE_ITEM ="vnd.android.cursor.item/vnd."+AUTHORITY ; /**     * 夸进程时发生在工作线程     *     * @param uri     * @return     */    @Nullable    @Override    public String getType(Uri uri) {        Log.i(TAG, "getType: current thread: " + Thread.currentThread().getName());        switch (sUriMatcher.match(uri)){            case USERINFO_CODE:            case COMPANY_CODE:                return CONTENT_TYPE;            case USERINFO_ITEM_CODE:            case COMPANY_ITEM_CODE:                return CONTNET_TYPE_ITEM;            default:                throw new RuntimeException("错误的 uri");        }    }

接着来看他的query 和 insert方法：

 /**     * 夸进程时发生在工作线程     *     * @param uri     * @param projection     * @param selection     * @param selectionArgs     * @param sortOrder     * @return     */    @Nullable    @Override    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {        Log.i(TAG, "query: current thread: " + Thread.currentThread().getName());        Cursor cursor = null;        switch (sUriMatcher.match(uri)) {            case USERINFO_CODE:                cursor = mDatabase.query(UserInfoDbHelper.TABLE_USER_INFO, projection, selection, selectionArgs, null, null, sortOrder);                break;            case USERINFO_ITEM_CODE:                String tel = uri.getPathSegments().get(1);                cursor = mDatabase.query(UserInfoDbHelper.TABLE_USER_INFO, projection, "tel_num = ?", new String[]{tel}, null, null, sortOrder);                break;            case COMPANY_CODE:                cursor = mDatabase.query(UserInfoDbHelper.TABLE_COMPANY, projection, selection, selectionArgs, null, null, sortOrder);                break;            case COMPANY_ITEM_CODE:                String cid = uri.getPathSegments().get(1);                cursor = mDatabase.query(UserInfoDbHelper.TABLE_COMPANY, projection, "id = ?", new String[]{cid}, null, null, sortOrder);                break;        }        return cursor;    }    /**     * 夸进程时发生在工作线程     *     * @param uri     * @param values     * @return     */    @Nullable    @Override    public Uri insert(Uri uri, ContentValues values) {        Log.i(TAG, "insert: current thread: " + Thread.currentThread().getName());        long newId = 0;        Uri newUri = null;        switch (sUriMatcher.match(uri)) {            case USERINFO_CODE:                newId = mDatabase.insert(UserInfoDbHelper.TABLE_USER_INFO, null, values);                newUri = Uri.parse("content://" + AUTHORITY + "/" + UserInfoDbHelper.TABLE_USER_INFO + "/" + newId);                break;            case COMPANY_CODE:                newId = mDatabase.insert(UserInfoDbHelper.TABLE_COMPANY, null, values);                newUri = Uri.parse("content://" + AUTHORITY + "/" + UserInfoDbHelper.TABLE_COMPANY + "/" + newId);                break;        }        if (newId > 0) return newUri;        throw new IllegalArgumentException("Failed to insert row info" + uri);    }

可以看到，利用UriMatcher得到要怎样查询，然后代用了 database的方法。

最后说一个方法：

 @Nullable    @Override    public Bundle call(String method, String arg, Bundle extras) {        return super.call(method, arg, extras);    }

可以利用这个方法，扩展出一些查询方式。

最后我们来看以下在清单文件中的注册：

  <provider            android:authorities="com.blueberry.test08.provider"            android:name=".SimpleContentProvider"            android:permission="com.blueberry.permission.provider"            android:process="com.blueberry.process1"            android:multiprocess="false"            >        provider>

这里主要的字段为 authorities ，他是ContentProvider的唯一标识。
permission，它分为读权限，和写权限对应为 android:readpermission 和
android:writepermission 。 multiprocess如果设置为true标识每个调用进程都拥有一个示例，负责只有所有进程只有一个示例。process字段使得它运行在一个名为com.blueberry.process1的进程中。

最后我们来看一下调用程序：

public class MainActivity extends AppCompatActivity {    private EditText etUserDesc,etUserPhoneNumber,etUserCompanyId;    private EditText etCompanyId,etCompanyBussiness,etCompanyAddress ;    private Button btnSubmitUserInfo,btnSubmitCompany;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        etUserDesc = (EditText) findViewById(R.id.et_user_desc);        etUserPhoneNumber = (EditText) findViewById(R.id.et_user_phone_number);        etUserCompanyId = (EditText) findViewById(R.id.et_user_company_id);        etCompanyId = (EditText) findViewById(R.id.et_company_id);        etCompanyBussiness  = (EditText) findViewById(R.id.et_company_bussiness);        etCompanyAddress = (EditText) findViewById(R.id.et_company_address);        btnSubmitUserInfo = (Button) findViewById(R.id.btn_save_userinfo);        btnSubmitCompany = (Button) findViewById(R.id.btn_save_company);        btnSubmitUserInfo.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                //存数用户信息数据                saveUserInfoRecord();                btnSubmitUserInfo.postDelayed(new Runnable() {                    @Override                    public void run() {                        queryUserInfo();                    }                },1000);            }        });        btnSubmitCompany.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                saveCompanyInfo();                btnSubmitCompany.postDelayed(new Runnable() {                    @Override                    public void run() {                      queryCompanyInfo();                    }                },1000) ;            }        });    }    /**     * 通过电话号码查询相关信息     */    private void queryUserInfo() {        Uri queryUri = Uri.parse("content://com.blueberry.test08.provider/userinfo/123456") ;        Cursor cursor = getContentResolver().query(queryUri,                new String[]{UserInfoDbHelper.DESC_COLUMN,UserInfoDbHelper.COMP_ID_COLUMN,UserInfoDbHelper.TEL_COLUMN}                ,null,null,null);        if(cursor.moveToFirst()){            Toast.makeText(this,                    " 描述信息"+cursor.getString(0)                    +" 公司id"+cursor.getString(1)                    +" 电话来自"+cursor.getString(2),Toast.LENGTH_SHORT).show();        }        cursor.close();    }    /**     * 存储用户信息到ContentProvider     */    private void saveUserInfoRecord() {        ContentValues newRecord = new ContentValues();        newRecord.put(UserInfoDbHelper.DESC_COLUMN,etUserDesc.getText().toString());        newRecord.put(UserInfoDbHelper.COMP_ID_COLUMN,etUserCompanyId.getText().toString());        newRecord.put(UserInfoDbHelper.TEL_COLUMN,etUserPhoneNumber.getText().toString());        getContentResolver().insert(SimpleContentProvider.USERINFO_CONTENT_URI,newRecord) ;    }    private void saveCompanyInfo() {        ContentValues newRecord = new ContentValues();        newRecord.put(UserInfoDbHelper.ID_COLUMN,etCompanyId.getText().toString());        newRecord.put(UserInfoDbHelper.BUSINESS_COLUMN,etCompanyBussiness.getText().toString());        newRecord.put(UserInfoDbHelper.ADDR_COLUMN,etCompanyAddress.getText().toString());        getContentResolver().insert(SimpleContentProvider.COMPANY_CONTENT_URI,newRecord);    }    private void queryCompanyInfo(){        Cursor cursor = getContentResolver().query(SimpleContentProvider.COMPANY_CONTENT_URI,                new String[]{UserInfoDbHelper.ID_COLUMN,UserInfoDbHelper.BUSINESS_COLUMN,UserInfoDbHelper.ADDR_COLUMN}                ,null,null,null);        StringBuffer sb = new StringBuffer();        while (cursor.moveToNext()){            sb.append("id: "+cursor.getString(0)+" business: "+cursor.getString(1)+" address: "+cursor.getString(2));            sb.append("\n");        }        Toast.makeText(this,sb.toString(),Toast.LENGTH_LONG).show();    }}

布局:

<?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.blueberry.test08.MainActivity">    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/et_user_desc"        android:hint="请输入用户描述信息"        android:contentDescription="用户描述信息"        />    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/et_user_phone_number"        android:hint="输入用户电话号码"        android:contentDescription="用户电话号码"        />    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/et_user_company_id"        android:hint="用户公司id"        android:contentDescription="用户公司id"        />    <Button        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/btn_save_userinfo"        android:text="存储用户信息"        />    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/et_company_id"        android:hint="公司id"        />    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/et_company_bussiness"        android:hint="请输入公司业务"        android:contentDescription="公司业务"        />    <EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/et_company_address"        android:hint="请输入公司地址"        android:contentDescription="请输入公司地址"        />    <Button        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:id="@+id/btn_save_company"        android:text="保存公司信息"        />LinearLayout>

Developer Guides

更多相关文章

随机推荐