Question

如何获得活动的当前屏幕亮度？

通过调用setBrightness(100)：

，以下方法可以将亮度设置为最大值

private void setBrightness(int brightness) {
    WindowManager.LayoutParams layoutParams = getWindow().getAttributes();
    layoutParams.screenBrightness = brightness/100.0f;
    getWindow().setAttributes(layoutParams);
}

我试图实现以下目标：

开始活动并保存当前亮度值
将亮度设置为最大
将亮度重置为某些事件的初始值

非常感谢！

Answer 1

尝试

int curBrightnessValue = android.provider.Settings.System.getInt(getContentResolver(), android.provider.Settings.System.SCREEN_BRIGHTNESS);

然后

   WindowManager.LayoutParams layoutParams = getWindow().getAttributes();
    layoutParams.screenBrightness = curBrightnessValue/100.0f;
    getWindow().setAttributes(layoutParams);

Answer 2

将亮度重置为默认值

WindowManager.LayoutParams layoutParams = getWindow().getAttributes();
layoutParams.screenBrightness = -1f;
getWindow().setAttributes(layoutParams);

默认值小于0表示使用首选屏幕亮度。

参考http://developer.android.com/reference/android/view/WindowManager.LayoutParams.html#screenBrightness

Answer 3

我在Android 17+上使用它（可能适用于较低的API）

    private void setScreenBrightnessTo(float brightness) {
        WindowManager.LayoutParams lp = getActivity().getWindow().getAttributes();
        if (lp.screenBrightness == brightness) {
            return;
        }

        lp.screenBrightness = brightness;
        getActivity().getWindow().setAttributes(lp);
    }

用途：

要将屏幕设置为MAX亮度（例如，当您显示条形码或其他内容时）：

setScreenBrightnessTo(BRIGHTNESS_OVERRIDE_FULL);

要重新回到用户之前的任何内容：

setScreenBrightnessTo(BRIGHTNESS_OVERRIDE_NONE);

Answer 4

有不同的亮度值： 1）如果您已经为活动亮度设置了一些值，则可以获取此值。如果未设置，则为-1F 2）亮度系统值获取示例：

    val activityBrightness = requireActivity().window.attributes.screenBrightness
    val systemBrightness = Settings.System.getInt(requireActivity().contentResolver, Settings.System.SCREEN_BRIGHTNESS) / 255
    currentBrightness = if (activityBrightness == -1F) systemBrightness.toFloat() * 100 else activityBrightness * 100

为活动窗口设置亮度的示例代码（请记住，该值可以在0.0到1.0之间）：

    currentBrightness = if (currentBrightness < 0) 0.0F else if (currentBrightness > 100) 100.0F else currentBrightness
    val layoutParams = activity?.window?.attributes
    if (layoutParams != null) {
        layoutParams.screenBrightness = currentBrightness / 100
        requireActivity().window.attributes = layoutParams
    }

Android中的屏幕亮度值

4 个答案: