Fix for issue Cleveroad#45 to allow tables with no data.

Author: Rubén Viguera Marañón

library/src/main/java/com/cleveroad/adaptivetablelayout/AdaptiveTableLayout.java

@@ -10,15 +10,16 @@
 import android.os.Bundle;
 import android.os.Parcel;
 import android.os.Parcelable;
+import android.util.AttributeSet;
+import android.view.MotionEvent;
+import android.view.View;
+import android.view.ViewGroup;
+
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.RequiresApi;
 import androidx.collection.SparseArrayCompat;
 import androidx.core.view.ViewCompat;
-import android.util.AttributeSet;
-import android.view.MotionEvent;
-import android.view.View;
-import android.view.ViewGroup;
 
 import java.util.ArrayList;
 import java.util.Collection;
@@ -867,31 +868,36 @@ private void addViewHolders(Rect filledArea) {
         int topRow = mManager.getRowByYWithShift(filledArea.top, mSettings.getCellMargin());
         int bottomRow = mManager.getRowByYWithShift(filledArea.bottom, mSettings.getCellMargin());
 
-        for (int i = topRow; i <= bottomRow; i++) {
-            for (int j = leftColumn; j <= rightColumn; j++) {
-                // item view holders
-                ViewHolder viewHolder = mViewHolders.get(i, j);
-                if (viewHolder == null && mAdapter != null) {
-                    addViewHolder(i, j, ViewHolderType.ITEM);
-                }
-            }
+        int columnCount = mManager.getColumnCount();
+        if (columnCount > 0) {
+            if (mManager.getRowCount() > 0) {
+                for (int i = topRow; i <= bottomRow; i++) {
+                    for (int j = leftColumn; j <= rightColumn; j++) {
+                        // item view holders
+                        ViewHolder viewHolder = mViewHolders.get(i, j);
+                        if (viewHolder == null && mAdapter != null) {
+                            addViewHolder(i, j, ViewHolderType.ITEM);
+                        }
+                    }
 
-            // row view headers holders
-            ViewHolder viewHolder = mHeaderRowViewHolders.get(i);
-            if (viewHolder == null && mAdapter != null) {
-                addViewHolder(i, isRTL() ? mManager.getColumnCount() : 0, ViewHolderType.ROW_HEADER);
-            } else if (viewHolder != null && mAdapter != null) {
-                refreshHeaderRowViewHolder(viewHolder);
+                    // row view headers holders
+                    ViewHolder viewHolder = mHeaderRowViewHolders.get(i);
+                    if (viewHolder == null && mAdapter != null) {
+                        addViewHolder(i, isRTL() ? columnCount : 0, ViewHolderType.ROW_HEADER);
+                    } else if (viewHolder != null && mAdapter != null) {
+                        refreshHeaderRowViewHolder(viewHolder);
+                    }
+                }
             }
-        }
 
-        for (int i = leftColumn; i <= rightColumn; i++) {
-            // column view header holders
-            ViewHolder viewHolder = mHeaderColumnViewHolders.get(i);
-            if (viewHolder == null && mAdapter != null) {
-                addViewHolder(0, i, ViewHolderType.COLUMN_HEADER);
-            } else if (viewHolder != null && mAdapter != null) {
-                refreshHeaderColumnViewHolder(viewHolder);
+            for (int i = leftColumn; i <= rightColumn; i++) {
+                // column view header holders
+                ViewHolder viewHolder = mHeaderColumnViewHolders.get(i);
+                if (viewHolder == null && mAdapter != null) {
+                    addViewHolder(0, i, ViewHolderType.COLUMN_HEADER);
+                } else if (viewHolder != null && mAdapter != null) {
+                    refreshHeaderColumnViewHolder(viewHolder);
+                }
             }
         }
 

library/src/main/java/com/cleveroad/adaptivetablelayout/AdaptiveTableManager.java

@@ -54,6 +54,12 @@ void clear() {
     }
 
     void init(int rowCount, int columnCount) {
+        if (rowCount < 0) {
+            rowCount = 0;
+        }
+        if (columnCount < 0) {
+            columnCount = 0;
+        }
         // create objects
         mRowHeights = new int[rowCount];
         mColumnWidths = new int[columnCount];