grid layout manger fix

.idea/codeStyles/Project.xml

@@ -1,29 +0,0 @@
-<component name="ProjectCodeStyleConfiguration">
-  <code_scheme name="Project" version="173">
-    <Objective-C-extensions>
-      <file>
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Import" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Macro" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Typedef" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Enum" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Constant" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Global" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Struct" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="FunctionPredecl" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Function" />
-      </file>
-      <class>
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Property" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="Synthesize" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="InitMethod" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="StaticMethod" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="InstanceMethod" />
-        <option name="com.jetbrains.cidr.lang.util.OCDeclarationKind" value="DeallocMethod" />
-      </class>
-      <extensions>
-        <pair source="cpp" header="h" fileNamingConvention="NONE" />
-        <pair source="c" header="h" fileNamingConvention="NONE" />
-      </extensions>
-    </Objective-C-extensions>
-  </code_scheme>
-</component>

.idea/encodings.xml

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Encoding" addBOMForNewFiles="with NO BOM" />
+</project>

app/src/main/java/ch/pizzamaxx/android/activity/CampaignProductListActivity.java

@@ -85,7 +85,7 @@ public class CampaignProductListActivity extends BaseActivity {
                         startActivityForResult(productPropertiesIntent, REQUEST_CODE_CAMPAIGN_PRODUCT_PROPERTIES);
                     }
                 });
-        campaignProductRecyclerView.addItemDecoration(new GridSpacesItemDecoration(DisplayHelper.dpToPx(12)));
+        campaignProductRecyclerView.addItemDecoration(new GridSpacesItemDecoration(2, 16, true));
         campaignProductRecyclerView.setAdapter(menuProductRecyclerAdapter);
     }
 

app/src/main/java/ch/pizzamaxx/android/fragment/MenuFragment.java

@@ -113,7 +113,7 @@ public class MenuFragment extends BaseFragment {
                         //showBottomsheetDialog(menuProductList.get(position));
                     }
                 });
-        menuProductRecyclerView.addItemDecoration(new GridSpacesItemDecoration(DisplayHelper.dpToPx(12)));
+        menuProductRecyclerView.addItemDecoration(new GridSpacesItemDecoration(2, 16, true));
         menuProductRecyclerView.setAdapter(menuProductRecyclerAdapter);
     }
 

app/src/main/java/ch/pizzamaxx/android/fragment/ProductFragment.java

@@ -113,7 +113,7 @@ public class ProductFragment extends BaseFragment {
                         //showBottomsheetDialog(productList.get(position));
                     }
                 });
-        customProductRecyclerView.addItemDecoration(new GridSpacesItemDecoration(DisplayHelper.dpToPx(12)));
+        customProductRecyclerView.addItemDecoration(new GridSpacesItemDecoration(2, 16, true));
         customProductRecyclerView.setAdapter(menuProductRecyclerAdapter);
     }
 

app/src/main/java/ch/pizzamaxx/android/view/GridSpacesItemDecoration.java

@@ -4,36 +4,43 @@ import android.graphics.Rect;
 import android.support.v7.widget.RecyclerView;
 import android.view.View;
 
+import ch.pizzamaxx.android.helper.DisplayHelper;
+
 /**
  * Created by cimenmus on 20/09/2017.
  */
 
-// This item decoration is for two column grid layout manager
 public class GridSpacesItemDecoration extends RecyclerView.ItemDecoration {
 
-    private int space;
+    private int spanCount;
+    private int spacing;
+    private boolean includeEdge;
 
-    public GridSpacesItemDecoration(int space) {
+    public GridSpacesItemDecoration(int spanCount, int spacingInDp, boolean includeEdge) {
-        this.space = space;
+        this.spanCount = spanCount;
+        this.spacing = DisplayHelper.dpToPx(spacingInDp);
+        this.includeEdge = includeEdge;
     }
 
     @Override
     public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
+        int position = parent.getChildAdapterPosition(view); // item position
+        int column = position % spanCount; // item column
 
-        outRect.left = space;
+        if (includeEdge) {
-        outRect.bottom = space;
+            outRect.left = spacing - column * spacing / spanCount; // spacing - column * ((1f / spanCount) * spacing)
-
+            outRect.right = (column + 1) * spacing / spanCount; // (column + 1) * ((1f / spanCount) * spacing)
-        // Add top margin only for the first item to avoid double space between items
-        if (parent.getChildLayoutPosition(view) == 0 ||  parent.getChildLayoutPosition(view) == 1)
-            outRect.top = space;
-        else
-            outRect.top = 0;
-
-        // Add right margin only for the first item in the line to avoid double space between items
-        if (parent.getChildLayoutPosition(view) % 2 == 1)
-            outRect.right = space;
-        else
-            outRect.right = 0;
 
+            if (position < spanCount) { // top edge
+                outRect.top = spacing;
+            }
+            outRect.bottom = spacing; // item bottom
+        } else {
+            outRect.left = column * spacing / spanCount; // column * ((1f / spanCount) * spacing)
+            outRect.right = spacing - (column + 1) * spacing / spanCount; // spacing - (column + 1) * ((1f /    spanCount) * spacing)
+            if (position >= spanCount) {
+                outRect.top = spacing; // item top
+            }
+        }
     }
 }

app/src/main/res/layout/row_menu_product.xml

@@ -6,7 +6,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     tools:ignore="MissingPrefix"
     android:orientation="vertical"
-    android:layout_width="160dp"
+    android:layout_width="match_parent"
     android:layout_height="wrap_content">
 
     <RelativeLayout
@@ -27,7 +27,7 @@
     </RelativeLayout>
 
     <RelativeLayout
-        android:layout_width="160dp"
+        android:layout_width="match_parent"
         android:layout_height="160dp"
         android:background="@color/white">