Android / Java：檢測設備是否有BACK攝像頭

Question

如何檢測設備背面是否有攝像頭？

這是我檢測設備是否有手電筒的代碼：

if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH) 
    || (_camera.getParameters().getSupportedFlashModes() != null)) hasFlashlight = true;
else hasFlashlight = false;

但即使設備只有沒有手電筒的前置攝像頭，它也是正確的。

Answer 1

對於API> = 9：您可以使用Camera.getCameraInfo ，如下所示：

int backCameraId = -1;
for(int i=0;i<Camera.getNumberOfCameras();i++){
    CameraInfo cameraInfo = new CameraInfo();
    Camera.getCameraInfo(i,cameraInfo);
    if(cameraInfo.facing==CameraInfo.CAMERA_FACING_BACK) {
        backCameraId = i;
        break;
    }
}
Log.d(TAG, "back camera exists ? "+(backCameraId>-1));
Log.d(TAG, "back camera id  :"+backCameraId);

對於API> = 21，建議您使用Camera2 API：

String backCameraId = null;
CameraManager manager = (CameraManager) getSystemService(Context.CAMERA_SERVICE);
for(String cameraId:manager.getCameraIdList()){
    CameraCharacteristics cameraCharacteristics = manager.getCameraCharacteristics(cameraId);
    Integer facing = cameraCharacteristics.get(CameraCharacteristics.LENS_FACING);
    if(facing==CameraMetadata.LENS_FACING_BACK) {
        backCameraId = cameraId;
        break;
    }
}
Log.d(TAG, "back camera exists ? "+(backCameraId!=null));
Log.d(TAG, "back camera id  :"+backCameraId);

Answer 2

嘗試檢查相機的數量：

import android.hardware.Camera;

int numberOfCameras = Camera.getNumberOfCameras();

如果它大於1，相當肯定有后置攝像頭。

Answer 3

public boolean isRearCameraAvailable(Context context) {
    return context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA);
}

檢查設備是否有遠離設備用戶的攝像頭