当我在字段上创建一个带有"primaryKey"注释的"实体"以使用room创建任何SQLite表时,Android Studio项目已成功构建。但是当我尝试使用复合主键创建一个"实体"时,无法构建项目。不幸的是,因为我在我的项目中使用"dagger 2",因此无法看到实际的构建错误。
注意:项目符合 Kotlin 编译器。
代码:
@Entity(tableName = "thread_users", primaryKeys = {"thread_id", "user_id"})
public class DMThreadUsers {
@ColumnInfo(name = "thread_id")
private String threadId;
@ColumnInfo(name = "user_id")
private String userId;
@ColumnInfo(name = "is_left")
private boolean isLeft;
public DMThreadUsers() {
}
public String getThreadId() {
return threadId;
}
public void setThreadId(String threadId) {
this.threadId = threadId;
}
public String getUserId() {
return userId;
}
public void setUserId(String userId) {
this.userId = userId;
}
public boolean isLeft() {
return isLeft;
}
public void setLeft(boolean left) {
isLeft = left;
}
}
主键字段应用@NonNull注释。您必须在 JAVA 中为主键字段注释@NonNull,在 KOTLIN 中需要初始化主键字段。
@Entity(tableName = "thread_users", primaryKeys = {"thread_id", "user_id"})
public class DMThreadUsers {
@NonNull
@ColumnInfo(name = "thread_id")
private String threadId;
@NonNull
@ColumnInfo(name = "user_id")
private String userId;
@ColumnInfo(name = "is_left")
private boolean isLeft;
public DMThreadUsers() {
}
public String getThreadId() {
return threadId;
}
public void setThreadId(String threadId) {
this.threadId = threadId;
}
public String getUserId() {
return userId;
}
public void setUserId(String userId) {
this.userId = userId;
}
public boolean isLeft() {
return isLeft;
}
public void setLeft(boolean left) {
isLeft = left;
}
}