Android 如何在SQL查询中反转布尔值？

我正在制作一个报警应用程序，我想写一个查询来切换一些报警属性，这是我的报警类

@Entity
data class Alarm(
    val label: String?,
    var isEnabled: Boolean,
    val ringTime: LocalTime,
    val occursOn: MutableSet<Day>,
    var isVibrationEnabled: Boolean,
    @PrimaryKey(autoGenerate = true) var id: Int? = null
)

---

这个应用程序编译得很好，所以看起来查询是有效的，但是在我执行它之后，值没有反转，并且保持不变。我相信你的问题不是切换，这是有效的

相反，问题在于WHERE子句没有选择行（或预期行），因此调用切换振动函数时作为参数传递的值不是报警或预期报警的id

例子 考虑以下示例（为了方便起见，使用Java而不是Kotlin）：-

AlarmEntityAlarm.java

public class Alarm {

    @PrimaryKey(autoGenerate = true)
    private long id;
    private String label;
    private boolean isEnabled;
    private boolean isVibrationEnabled;

    public Alarm() {

    }

    public Alarm(String label, boolean isEnabled, boolean isVibrationEnabled) {
        this.label = label;
        this.isEnabled = isEnabled;
        this.isVibrationEnabled = isVibrationEnabled;
    }

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getLabel() {
        return label;
    }

    public void setLabel(String label) {
        this.label = label;
    }

    public boolean isEnabled() {
        return isEnabled;
    }

    public void setEnabled(boolean enabled) {
        isEnabled = enabled;
    }

    public boolean isVibrationEnabled() {
        return isVibrationEnabled;
    }

    public void setVibrationEnabled(boolean vibrationEnabled) {
        isVibrationEnabled = vibrationEnabled;
    }
}

@Dao
public interface AlarmDao {

    @Insert
    long[] insertAlarm(Alarm... alarms);
    @Insert
    long insertAlarm(Alarm alarm);
    @Query("SELECT * FROM Alarm")
    List<Alarm> getAllAlarms();
    @Query("UPDATE Alarm SET isVibrationEnabled = NOT isVibrationEnabled WHERE id = :id")
    int toggleVibration(long id);
}

• 为方便起见，减少了列集

AlarmDao.java

public class Alarm {

    @PrimaryKey(autoGenerate = true)
    private long id;
    private String label;
    private boolean isEnabled;
    private boolean isVibrationEnabled;

    public Alarm() {

    }

    public Alarm(String label, boolean isEnabled, boolean isVibrationEnabled) {
        this.label = label;
        this.isEnabled = isEnabled;
        this.isVibrationEnabled = isVibrationEnabled;
    }

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getLabel() {
        return label;
    }

    public void setLabel(String label) {
        this.label = label;
    }

    public boolean isEnabled() {
        return isEnabled;
    }

    public void setEnabled(boolean enabled) {
        isEnabled = enabled;
    }

    public boolean isVibrationEnabled() {
        return isVibrationEnabled;
    }

    public void setVibrationEnabled(boolean vibrationEnabled) {
        isVibrationEnabled = vibrationEnabled;
    }
}

@Dao
public interface AlarmDao {

    @Insert
    long[] insertAlarm(Alarm... alarms);
    @Insert
    long insertAlarm(Alarm alarm);
    @Query("SELECT * FROM Alarm")
    List<Alarm> getAllAlarms();
    @Query("UPDATE Alarm SET isVibrationEnabled = NOT isVibrationEnabled WHERE id = :id")
    int toggleVibration(long id);
}

---

i、 e.对于Alarm001，IsVibrationEnabled值已从true切换为false

@forpas布尔类型如果没有布尔类型，我会假设false为0，true为1。表中是否存在id等于您绑定为

：alarmId

的值的行？显然这就是问题所在，正如米凯特指出的那样

05-30 10:34:33.853 D/ALARMBEFORE: Label = Alarm001 Enabaled = true Vibration =  true
05-30 10:34:33.853 D/ALARMBEFORE: Label = Alarm002 Enabaled = false Vibration =  false
05-30 10:34:33.856 D/ALARMAFTER: Label = Alarm001 Enabaled = true Vibration =  false
05-30 10:34:33.856 D/ALARMAFTER: Label = Alarm002 Enabaled = false Vibration =  false