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package com.changcheng.sqlite.provider;
import com.changcheng.sqlite.MyOpenHelper;
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 ContactContentProvider extends ContentProvider {
// 通过UriMatcher匹配外部请求
private static UriMatcher uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
// 通过openHelper进行数据库读写
private MyOpenHelper openHelper;
// 匹配状态常量
private static final int CONTACT_LIST = 1;
private static final int CONTACT = 2;
// 表名
private static final String tableName = "contacts";
// 添加Uri
static {
uriMatcher.addURI("com.changcheng.sqlite.provider", "contact",
CONTACT_LIST);
uriMatcher.addURI("com.changcheng.sqlite.provider", "contact/#",
CONTACT);
}
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
SQLiteDatabase db = this.openHelper.getWritableDatabase();
int result;
switch (uriMatcher.match(uri)) {
case CONTACT_LIST:
result = db.delete(tableName, selection, selectionArgs);
break;
case CONTACT:
long id = ContentUris.parseId(uri);
String where = "_id=" + id;
if (selection != null && !"".equals(selection)) {
where = where + " and " + selection;
}
result = db.delete(tableName, where, selectionArgs);
break;
default:
throw new IllegalArgumentException("Uri IllegalArgument:" + uri);
}
return result;
}
@Override
public String getType(Uri uri) {
switch (uriMatcher.match(uri)) {
case CONTACT_LIST:// 集合类型必须在前面加上vnd.android.cursor.dir/
return "vnd.android.cursor.dir/contactlist";
case CONTACT:// 非集合类型必须在前面加上vnd.android.cursor.item/
return "vnd.android.cursor.item/contact";
default:
throw new IllegalArgumentException("Uri IllegalArgument:" + uri);
}
}
@Override
public Uri insert(Uri uri, ContentValues values) {
SQLiteDatabase db = this.openHelper.getWritableDatabase();
long id;
switch (uriMatcher.match(uri)) {
case CONTACT_LIST:
// 因为后台需要生成SQL语句，当values为null时，必须提第二个参数。生成的SQL语句才不会出错！
id = db.insert(tableName, "_id", values);
return ContentUris.withAppendedId(uri, id);
case CONTACT:
id = db.insert(tableName, "_id", values);
String uriPath = uri.toString();
String path = uriPath.substring(0, uriPath.lastIndexOf("/")) + id;
return Uri.parse(path);
default:
throw new IllegalArgumentException("Uri IllegalArgument:" + uri);
}
}
@Override
public boolean onCreate() {
this.openHelper = new MyOpenHelper(this.getContext());
return true;
}
@Override
public Cursor query(Uri uri, String[] projection, String selection,
String[] selectionArgs, String sortOrder) {
SQLiteDatabase db = this.openHelper.getWritableDatabase();
switch (uriMatcher.match(uri)) {
case CONTACT_LIST:
return db.query(tableName, projection, selection, selectionArgs,
null, null, sortOrder);
case CONTACT:
long id = ContentUris.parseId(uri);
String where = "_id=" + id;
if (selection != null && !"".equals(selection)) {
where = where + " and " + selection;
}
return db.query(tableName, projection, where, selectionArgs, null,
null, sortOrder);
default:
throw new IllegalArgumentException("Uri IllegalArgument:" + uri);
}
}
@Override
public int update(Uri uri, ContentValues values, String selection,
String[] selectionArgs) {
SQLiteDatabase db = this.openHelper.getWritableDatabase();
int result;
switch (uriMatcher.match(uri)) {
case CONTACT_LIST:
result = db.update(selection, values, selection, selectionArgs);
break;
case CONTACT:
long id = ContentUris.parseId(uri);
String where = "_id=" + id;
if (selection != null && !"".equals(selection)) {
where = where + " and " + selection;
}
result = db.update(tableName, values, where, selectionArgs);
break;
default:
throw new IllegalArgumentException("Uri IllegalArgument:" + uri);
}
return result;
}
}
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