Fix camera face swith bug

Signed-off-by: Leo Ma <begeekmyfriend@gmail.com>

app/src/main/java/net/ossrs/yasea/SrsCameraView.java

@@ -47,7 +47,7 @@ public class SrsCameraView extends GLSurfaceView implements GLSurfaceView.Render
 
     private Camera mCamera;
     private ByteBuffer mGlPreviewBuffer;
-    private int mCamId = Camera.CameraInfo.CAMERA_FACING_FRONT;
+    private int mCamId = -1;
     private int mPreviewRotation = 90;
 
     private Thread worker;
@@ -193,7 +193,7 @@ public class SrsCameraView extends GLSurfaceView implements GLSurfaceView.Render
         if (mCamera != null) {
             return false;
         }
-        if (mCamId > (Camera.getNumberOfCameras() - 1) || mCamId < 0) {
+        if (mCamId > (Camera.getNumberOfCameras() - 1)) {
             return false;
         }
 
@@ -220,6 +220,7 @@ public class SrsCameraView extends GLSurfaceView implements GLSurfaceView.Render
         });
         worker.start();
 
+        if (mCamId < 0) {
             Camera.CameraInfo info = new Camera.CameraInfo();
             int numCameras = Camera.getNumberOfCameras();
             for (int i = 0; i < numCameras; i++) {
@@ -230,6 +231,9 @@ public class SrsCameraView extends GLSurfaceView implements GLSurfaceView.Render
                     break;
                 }
             }
+        } else {
+            mCamera = Camera.open(mCamId);
+        }
         if (mCamera == null) {
             mCamera = Camera.open();
             mCamId = 0;