How to turn on the Android Flashlight

Question

Update

Check out my answer

Original

I\'m trying to turn on the camera flashlight on the LG Revolution within my pro

Answer 1

I thought I would update this with some bullet prof code that works on almost all 4.0+ devices.

public void turnOn() {
    camera = Camera.open();
    try {
        Parameters parameters = camera.getParameters();
        parameters.setFlashMode(getFlashOnParameter());
        camera.setParameters(parameters);

        camera.setPreviewTexture(new SurfaceTexture(0));

        camera.startPreview();
        camera.autoFocus(this);
    } catch (Exception e) {
        // We are expecting this to happen on devices that don't support autofocus.
    }
}

private String getFlashOnParameter() {
    List flashModes = camera.getParameters().getSupportedFlashModes();

    if (flashModes.contains(FLASH_MODE_TORCH)) {
        return FLASH_MODE_TORCH;
    } else if (flashModes.contains(FLASH_MODE_ON)) {
        return FLASH_MODE_ON;
    } else if (flashModes.contains(FLASH_MODE_AUTO)) {
        return FLASH_MODE_AUTO;
    }
    throw new RuntimeException();
}

The real key is setting that fake SurfaceTexture so that the preview will actually start. Turning it off is very easy as well

public void turnOff() {
        try {
            camera.stopPreview();
            camera.release();
            camera = null;
        } catch (Exception e) {
            // This will happen if the camera fails to turn on.
        }
}