* 内置手电筒按钮,当光线太暗时，自动显示手电筒 fix(#58)

*  生成二维码时Logo支持自定义大小 fix(#62)

lib/src/main/java/com/king/zxing/CaptureFragment.java

@@ -38,6 +38,7 @@ public class CaptureFragment extends Fragment implements OnCaptureCallback {
 
     private SurfaceView surfaceView;
     private ViewfinderView viewfinderView;
+    private View ivTorch;
 
     private CaptureHelper mCaptureHelper;
 
@@ -67,7 +68,12 @@ public class CaptureFragment extends Fragment implements OnCaptureCallback {
     public void initUI(){
         surfaceView = mRootView.findViewById(getSurfaceViewId());
         viewfinderView = mRootView.findViewById(getViewfinderViewId());
-        mCaptureHelper = new CaptureHelper(this,surfaceView,viewfinderView);
+        int ivTorchId = getIvTorchId();
+        if(ivTorchId != 0){
+            ivTorch = mRootView.findViewById(ivTorchId);
+            ivTorch.setVisibility(View.INVISIBLE);
+        }
+        mCaptureHelper = new CaptureHelper(this,surfaceView,viewfinderView,ivTorch);
         mCaptureHelper.setOnCaptureCallback(this);
     }
 
@@ -96,7 +102,6 @@ public class CaptureFragment extends Fragment implements OnCaptureCallback {
         return R.id.viewfinderView;
     }
 
-
     /**
      * 预览界面{@link #surfaceView} 的id
      * @return
@@ -105,6 +110,14 @@ public class CaptureFragment extends Fragment implements OnCaptureCallback {
         return R.id.surfaceView;
     }
 
+    /**
+     * 获取 {@link #ivTorch} 的ID
+     * @return  默认返回{@code R.id.ivTorch}, 如果不需要手电筒按钮可以返回0
+     */
+    public int getIvTorchId(){
+        return R.id.ivTorch;
+    }
+
     /**
      * Get {@link CaptureHelper}
      * @return {@link #mCaptureHelper}