1. 创建实体类
@Entity(tableName = "user")
public class User extends OrmObject {
@PrimaryKey(autoGenerate = true)
private Integer id;
private String name;
private String introduction;
getter...
setter...
/**
* convert values bucket to user
*
* @param valuesBucket values bucket
* @return user
*/
public User fromValues(ValuesBucket valuesBucket) {
name = valuesBucket.getString("name");
introduction = valuesBucket.getString("introduction");
return this;
}
}
2. 创建UserOrmDatabase
@Database(entities = {
User.class, Note.class}, version = 1)
public abstract class UserOrmDatabase extends OrmDatabase {
/**
* Configuring this Database's name.
*/
public static final String DATABASE_NAME = "User.db";
/**
* Configuring this Database's alias.
*/
public static final String DATABASE_NAME_ALIAS = "User";
}
3. 创建UserDataAbility并重写其中插入和查询的方法
public class UserDataAbility extends Ability {
private static final HiLogLabel LABEL_LOG = new HiLogLabel(3, 0xD001100, "TAG");
public final static String URI = "dataability:///work.wxmx.metadatabindingstudy.UserDataAbility";
private static final int ERR_CODE = -1;
private static final String ROW_ID = "id";
private OrmContext ormContext = null;
@Override
public void onStart(Intent intent) {
super.onStart(intent);
HiLog.info(LABEL_LOG, "UserDataAbility onStart");
DatabaseHelper manager = new DatabaseHelper(this);
ormContext = manager.getOrmContext(
UserOrmDatabase.DATABASE_NAME_ALIAS,
UserOrmDatabase.DATABASE_NAME,
UserOrmDatabase.class);
}
@Override
public ResultSet query(Uri uri, String[] columns, DataAbilityPredicates predicates) {
//查询数据库
OrmPredicates ormPredicates = DataAbilityUtils.createOrmPredicates(predicates, User.class);
ResultSet resultSet = ormContext.query(ormPredicates, columns);
if (resultSet == null) {
HiLog.info(LABEL_LOG, "resultSet is null");
}
return resultSet;
}
@Override
public int insert(Uri uri, ValuesBucket value) {
HiLog.info(LABEL_LOG, "insert...", "");
User user = new User();
if (ormContext.insert(user.fromValues(value))) {
ormContext.flush();
DataAbilityHelper.creator(this, uri).notifyChange(uri);
return (int) user.getRowId();
}
return ERR_CODE;
}
// ... 其他方法略
}
4. 创建布局
<?xml version="1.0" encoding="utf-8"?>
<DirectionalLayout
xmlns:ohos="http://schemas.huawei.com/res/ohos"
ohos:height="match_parent"
ohos:width="match_parent"
ohos:orientation="vertical">
<DirectionalLayout
ohos:height="match_content"
ohos:width="match_parent"
ohos:orientation="horizontal">
<Text
ohos:height="match_content"
ohos:width="match_content"
ohos:text="name: "
ohos:text_size="40fp"
ohos:visibility="visible"/>
<TextField
ohos:id="$+id:name_text_field"
ohos:height="match_content"
ohos:width="match_content"
ohos:align_parent_right="true"
ohos:hint="name"
ohos:multiple_lines="false"
ohos:right_margin="15vp"
ohos:text_size="40fp"/>
</DirectionalLayout>
<DirectionalLayout
ohos:height="match_content"
ohos:width="match_parent"
ohos:orientation="horizontal">
<Text
ohos:height="match_content"
ohos:width="match_content"
ohos:text="intro: "
ohos:text_size="40fp"
ohos:visibility="visible"/>
<TextField
ohos:id="$+id:introduction_text_field"
ohos:height="match_content"
ohos:width="match_content"
ohos:align_parent_right="true"
ohos:hint="introduction"
ohos:max_text_lines="10"
ohos:multiple_lines="false"
ohos:right_margin="15vp"
ohos:text_size="40fp"/>
</DirectionalLayout>
<DirectionalLayout
ohos:height="match_content"
ohos:width="match_parent"
ohos:orientation="horizontal">
<Button
ohos:id="$+id:insert_btn"
ohos:height="match_content"
ohos:width="match_content"
ohos:background_element="gray"
ohos:text="insert"
ohos:text_size="40fp"/>
<Button
ohos:left_margin="20vp"
ohos:id="$+id:query_btn"
ohos:height="match_content"
ohos:width="match_content"
ohos:background_element="gray"
ohos:text="query"
ohos:text_size="40fp"/>
</DirectionalLayout>
<Text
ohos:text="AAA"
ohos:text_size="20fp"
ohos:id="$+id:result_text"
ohos:multiple_lines="true"
ohos:height="match_content"
ohos:width="match_content"/>
</DirectionalLayout>
效果图如下:
5. 在MainAbilitySlice中添加处理事件的逻辑
public class MainAbilitySlice extends AbilitySlice {
DataAbilityHelper mHelper;
private static final HiLogLabel LABEL_LOG = new HiLogLabel(3, 0xD001100, "TAG");
@Override
public void onStart(Intent intent) {
super.onStart(intent);
super.setUIContent(ResourceTable.Layout_ability_main);
mHelper = DataAbilityHelper.creator(this);
Button insertBtn = (Button) findComponentById(ResourceTable.Id_insert_btn);
Button queryBtn = (Button) findComponentById(ResourceTable.Id_query_btn);
Text nameText = (Text) findComponentById(ResourceTable.Id_name_text_field);
Text resultText = (Text) findComponentById(ResourceTable.Id_result_text);
Text introductionText = (Text) findComponentById(ResourceTable.Id_introduction_text_field);
insertBtn.setClickedListener(new Component.ClickedListener() {
@Override
public void onClick(Component component) {
ValuesBucket bucket = new ValuesBucket();
bucket.putString("name", nameText.getText());
bucket.putString("introduction", introductionText.getText());
try {
mHelper.insert(Uri.parse(UserDataAbility.URI), bucket);
} catch (DataAbilityRemoteException e) {
e.printStackTrace();
}
}
});
queryBtn.setClickedListener(new Component.ClickedListener() {
@Override
public void onClick(Component component) {
HiLog.info(LABEL_LOG, "queryData Ability start");
// 构造查询条件
DataAbilityPredicates predicates = new DataAbilityPredicates();
predicates.like("name", "%" + nameText.getText() + "%");
// 进行查询
String[] columns = new String[]{
"id", "name", "introduction"};
Uri uri = Uri.parse(UserDataAbility.URI);
ResultSet resultSet = null;
try {
resultSet = mHelper.query(uri, columns, predicates);
} catch (DataAbilityRemoteException e) {
e.printStackTrace();
}
// 处理结果
resultSet.goToFirstRow();
StringBuilder builder = new StringBuilder();
while (resultSet.goToNextRow()) {
// 在此处理ResultSet中的记录;
String name = resultSet.getString(1);
String introduction = resultSet.getString(2);
HiLog.info(LABEL_LOG, "name=" + name);
HiLog.info(LABEL_LOG, "introduction=" + introduction);
builder.append(name + ": " + introduction + "\n");
}
resultText.setText(builder.toString());
}
});
}
@Override
public void onActive() {
super.onActive();
}
@Override
public void onForeground(Intent intent) {
super.onForeground(intent);
}
}
效果图
