集成页面结构#

---
title: "Light brightness changed"
trigger: light.brightness_changed
domain: light
description: "Triggers after the brightness of one or more lights changes."
related_triggers:
  - light.brightness_crossed_threshold
  - light.turned_on
---

The **Light brightness changed** trigger fires after...
Use it to...

{% include triggers/ui_header.md %}

To use this trigger in an automation:

1. Go to {% my automations title="**Settings** > **Automations & scenes**" %}.
2. Open an existing automation, or select **Create automation** > **Create new automation**.
3. In the **When** section, select **Add trigger**.
4. From the search box, search for and select **Light brightness changed**.
5. Select what you want to monitor. Under **By target** (see [Targets](#targets)), pick... You can also select a floor, a device, a specific entity, or a label.
6. From the triggers shown for that target, select...
7. Under **Trigger when** (see [Behavior](#behavior-with-multiple-targets)), pick **Any**, **First**, or **Last** to control how multiple targets interact.
8. Under **Threshold type**, set how much the level has to change before the trigger fires.
9. Under **Another field**, set...
10. Select **Save**.

### UI 中的选项

<!-- Note that there are no "type" or "default" fields for UI options, as you have in YAML. They are not rendered for the UI options. -->

{% options_ui %}
Threshold type:
  description: How much the brightness has to change before the trigger fires, as a percentage of full brightness. Can be a fixed number, or reference a helper entity that provides the value.
  required: false
{% endoptions_ui %}

{% include triggers/yaml_header.md %}

In YAML, refer to this trigger as `light.brightness_changed`. A basic example looks like this:

{% example %}
trigger: |
  trigger: light.brightness_changed
  target:
    entity_id: light.living_room
  options:
    threshold: 10
behavior:
  description: >
    当针对多个传感器时，控制触发何时触发。接受 `any`、`first` 或 `last`。
  required: false
  type: string
  default: any
{% endexample %}

这会在客厅灯光亮度变化至少百分之十时触发。

### YAML 中的选项

YAML 有时提供一些通过 UI 无法获得的、用于更复杂用例的额外选项。

<!-- If the option has a default value, set the required field to false. -->

{% options_yaml %}
threshold:
  description: >
    亮度在触发前必须变化的最小量（以百分比为单位）。接受一个数字，或对带百分比单位的 `input_number`、`number` 或 `sensor` entity 的引用。
  required: true
  type: any
{% endoptions_yaml %}

<!-- Keep the "include" below if your integration supports targets -->
{% include triggers/targets.md %}

{% include triggers/behavior.md %}

## 需要了解的信息

- 在此添加额外信息。

{% include triggers/try_it.md %}

{% include triggers/more_examples.md %}

### 自动化：将吊扇速度与顶灯同步

When you dim the ceiling light down, slow the fan down too. 当你调低天花板灯光时，也降低风扇转速。这是一个经典的 "场景氛围" 自动化，保持房间协调一致。

- **Trigger**: Light brightness changed
  - **Target**: Living room ceiling light
  - **Threshold type**: 10
- **Action**: Set fan speed

{% details "YAML example for a ceiling-light-linked fan" %}

{% example %}
automation: |
  alias: "Match fan to ceiling light"
  triggers:
    - trigger: light.brightness_changed
      target:
        entity_id: light.living_room_ceiling
      options:
        threshold: 10
  actions:
    - action: fan.set_percentage
      target:
        entity_id: fan.living_room
      data:
        percentage: "{{ state_attr('light.living_room_ceiling', 'brightness_pct') | int }}"
{% endexample %}

{% enddetails %}

{% include triggers/stuck.md %}

{% include triggers/related.md %}

---
title: "Light is on"
condition: light.is_on
domain: light
description: "Tests if one or more lights are on."
related_conditions:
  - light.is_off
  - light.is_brightness
---

The **Light is on** condition passes when...
Use it to...

{% include conditions/ui_header.md %}

To use this condition in an automation:

1. Go to {% my automations title="**Settings** > **Automations & scenes**" %}.
2. Open an existing automation, or select **Create automation** > **Create new automation**.
3. In the **And if** section, select **Add condition**.
4. From the search box, search for and select **Light is on**.
5. Select what you want to check. Under **By target** (see [Targets](#targets)), pick the area your ... is in (like your living room or bedroom).
   You can also select a floor, a device, a specific entity, or a label.
6. Under **Condition passes if** (see [Behavior](#behavior-with-multiple-targets)), pick **Any** or **All**.
7. Select **Save**.

### UI 中的选项

{% options_ui %}
Condition passes if:
  description: When multiple lights are targeted, controls how results combine. Pick **Any** to pass if at least one targeted light is on, or **All** to pass only when every targeted light is on.
{% endoptions_ui %}

{% include conditions/yaml_header.md %}

In YAML, refer to this condition as `light.is_on`. A basic example looks like this:

{% example %}
condition: |
  condition: light.is_on
  target:
    entity_id: light.living_room
{% endexample %}

当客厅灯光当前为开启状态时通过。

### YAML 中的选项

YAML 有时提供一些通过 UI 无法获得的、用于更复杂用例的额外选项。

{% options_yaml %}
behavior:
  description: >
    当针对多个灯时，控制结果如何合并。接受 `all` 或 `any`。
  required: false
  type: string
  default: any
{% endoptions_yaml %}

<!-- Keep the two "includes" below if your integration supports targets -->
{% include conditions/targets.md %}

{% include conditions/behavior.md %}

## 需要了解的信息

- 在此添加额外信息。

{% include conditions/try_it.md %}

{% include conditions/more_examples.md %}

### 自动化：仅在客厅有灯光时播报门铃

当门铃响起时，仅当客厅灯已开启时才通过客厅音箱播报。当房间无人时保持房子安静。

- **Trigger**: State: Doorbell button pressed
- **Condition**: Light is on
  - **Target**: Living room light
  - **Condition passes if**: Any
- **Action**: Play media

{% details "YAML example for a doorbell announcement gated on lights" %}

{% example %}
automation: |
  alias: "Doorbell announce when living room lit"
  triggers:
    - trigger: state
      entity_id: binary_sensor.doorbell
      to: "on"
  conditions:
    - condition: light.is_on
      target:
        entity_id: light.living_room
      options:
        behavior: any
  actions:
    - action: media_player.play_media
      target:
        entity_id: media_player.living_room
      data:
        media_content_id: "media-source://tts/cloud?message=Someone+is+at+the+door"
        media_content_type: music
        announce: true
{% endexample %}

{% enddetails %}

{% include conditions/stuck.md %}

{% include conditions/related.md %}

---
title: "Turn on a light"
action: light.turn_on
domain: light
description: "Turn a light on. Optionally set brightness, color, color temperature, an effect, or a transition."
since: "0.7"
related_actions:
  - light.turn_off
  - light.toggle
---

The **Turn on a light** action turns a light on...
This action works with any light {% term entity %} in Home Assistant...
If the light is already on, calling the action...

{% include actions/ui_header.md %}

To turn a light on from an automation or a script:

1. Go to {% my automations title="**Settings** > **Automations & scenes**" %}.
2. Open an existing automation or script, or select **Create automation** > **Create new automation**.
3. If you're setting up a new automation, add a trigger in the **When** section. Scripts don't need a trigger. They run when something else calls them.
4. In the **Then do** section, select **Add action**.
5. From the search box, search for and select **Turn on light**.
6. Select what you want to control. Under **By target** (see [Targets](#targets)), pick the area your ... is in (like your hallway or entryway). You can also select a floor, a device, a specific entity, or a label.
7. Select **Save**.

### UI 中的选项

{% options_ui %}
Transition:
  description: How long, in seconds, it takes to get to the next state. Use this for a smooth fade instead of switching instantly.
{% endoptions_ui %}

{% include actions/yaml_header.md %}

In YAML, refer to this action as `light.turn_on`. A basic example looks like this:

{% example %}
action: |
  action: light.turn_on
  target:
    entity_id: light.kitchen
{% endexample %}

以之前的亮度和颜色开启 `light.kitchen`。

### YAML 中的选项

YAML 有时提供一些通过 UI 无法获得的、用于更复杂用例的额外选项。

{% options_yaml %}
transition:
  description: >
    到达下一个状态所需的时间，以秒为单位。使用此选项可以平滑淡入淡出，而不是瞬间切换。
  required: false
  type: integer
{% endoptions_yaml %}

{% include actions/targets.md %}

## 需要了解的信息

- 在此添加额外信息。

{% include actions/try_it.md %}

{% include actions/more_examples.md %}

### 自动化：设置舒适的暖白光

When you start winding down in the evening, dim the kitchen light to a warm white tone. 当你在傍晚开始放松时，将厨房灯光调至温暖的白光。

- **Action**: Turn on light
  - **Target**: Kitchen light
  - **Brightness percentage**: 80
- **Color**: warm_white

{% details "YAML example for a cozy warm white scene" %}

{% example %}
action: |
  action: light.turn_on
  target:
    entity_id: light.kitchen
  data:
    brightness_pct: 80
    color_name: warm_white
{% endexample %}

{% enddetails %}

{% include actions/stuck.md %}

{% include actions/related.md %}