diff --git a/app/src/main/java/org/ntlab/radishforandroidstudio/framework/RWT/RWTButton.java b/app/src/main/java/org/ntlab/radishforandroidstudio/framework/RWT/RWTButton.java
index 38d66a6..ba01933 100644
--- a/app/src/main/java/org/ntlab/radishforandroidstudio/framework/RWT/RWTButton.java
+++ b/app/src/main/java/org/ntlab/radishforandroidstudio/framework/RWT/RWTButton.java
@@ -5,7 +5,7 @@
 import org.ntlab.radishforandroidstudio.framework.listener.TouchListener;
 
 public class RWTButton implements TouchListener {
-    private RWTSprite[] sprite = null;
+    private RWTSprite[] sprite = new RWTSprite[2];
 
     public RWTButton(final RWTLayer layer) {
         sprite = new RWTSprite[2];
diff --git a/app/src/main/java/org/ntlab/radishforandroidstudio/framework/RWT/RWTSprite.java b/app/src/main/java/org/ntlab/radishforandroidstudio/framework/RWT/RWTSprite.java
index de02231..ffebc9e 100644
--- a/app/src/main/java/org/ntlab/radishforandroidstudio/framework/RWT/RWTSprite.java
+++ b/app/src/main/java/org/ntlab/radishforandroidstudio/framework/RWT/RWTSprite.java
@@ -23,8 +23,6 @@
  */
 public class RWTSprite implements RWTDrawable {
     private int[] textureId = null;
-    private RWTImageLoader texLoader;
-    private Texture tex;
     private ImageComponent2D image = null;
     private boolean isDraw = true;
 
@@ -98,11 +96,11 @@
      *       Bitmap.createScaledBitmap(robot, 100, 100, false);のやつ
      */
     public void setTexture(Resources res, int id, boolean isEnableAlpha) {
-        texLoader = new RWTImageLoader(res, id,
+        RWTImageLoader texLoader = new RWTImageLoader(res, id,
                                         TextureLoader.BY_REFERENCE | TextureLoader.Y_UP,
                                         isEnableAlpha ? ImageComponent2D.FORMAT_RGBA : ImageComponent2D.FORMAT_RGB);
         image = texLoader.getImage();
-        tex = texLoader.getTexture();
+        Texture tex = texLoader.getTexture();
         Log.v("moji", "faaa");
         Log.v("moji",  ((Double)(texLoader.getSize().getX())).toString() + ", " + ((Double)(texLoader.getSize().getY())).toString());
         Log.v("moji", "faaa");
@@ -127,7 +125,6 @@
             return;
         }
 
-        boolean isNullTextureId = textureId == null;
         if (textureId == null) {
             textureId = new int[1];
             textureId[0] = gc3D.loadImage(image);