所有按钮添加的ImageButtons矩阵变成黑色

Question

这就是它在开始时的样子。在我创建新项目并添加了一些修改后的代码后，视图会变成这样的smth（注意矩阵中只有那些按钮是黑色的）：

以下是我的xml文件包含的内容：

<RelativeLayout  xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent" 
    android:layout_height="match_parent" >

    <LinearLayout 
        android:orientation="vertical"
        android:layout_width="match_parent" 
        android:layout_height="wrap_content" 
        android:id="@+id/main_container" >
    </LinearLayout> 

    <RelativeLayout 
        android:layout_below="@id/main_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >
    <Button 
        android:layout_centerHorizontal="true"
        android:id="@+id/refresh_button"    
        android:layout_gravity="center"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" 
        android:text="@string/refresh"/>

    <TextView
        android:layout_centerHorizontal="true"
        android:layout_below="@id/refresh_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/minesLeft"
        android:text="@string/minesLeft"/>

    <TextView 
        android:layout_centerHorizontal="true"
        android:layout_below="@id/refresh_button"
        android:layout_toRightOf="@+id/minesLeft"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/minesLeftCounter"/>

    </RelativeLayout>   



</RelativeLayout>

这就是我创造这个的方式：

map = new ArrayList<   ArrayList<ImageButton> >();
        LinearLayout mainContainer = (LinearLayout) c.findViewById(R.id.main_container);



                //Params used for cells
                TableRow.LayoutParams params = new TableRow.LayoutParams(
                        0, ViewGroup.LayoutParams.WRAP_CONTENT, 1.0f
                );
                int pixelsToDp = convertToPixelsDp(-4.5f);
                params.setMargins(pixelsToDp, pixelsToDp, pixelsToDp, pixelsToDp);

                //Params used for rows
                TableRow.LayoutParams rowParams = new TableRow.LayoutParams(
                        ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT
                );
                rowParams.setMargins(0, 0, 0, 0);

                //Params used for table
                TableLayout.LayoutParams tableParams = new TableLayout.LayoutParams(
                        ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT
                );
                tableParams.setMargins(0, 0, 0, 0);

                //Table generation
                TableLayout table = new TableLayout(mAppContext);
                table.setLayoutParams(tableParams);
                table.setShowDividers(TableLayout.SHOW_DIVIDER_NONE);
                table.setStretchAllColumns(true);

                for(int i = 0; i < 15; i++){
                    ArrayList<ImageButton> rowOfList = new ArrayList<ImageButton>();
                    TableRow row = new TableRow(mAppContext);

                    row.setShowDividers(TableRow.SHOW_DIVIDER_NONE);
                    row.setLayoutParams(rowParams);

                    for(int j = 0; j < 10; j++){

                        ImageButton btn = new ImageButton(mAppContext);

                        btn.setPadding(0, 0, 0, 0);
                        btn.setLayoutParams(params);
                        btn.setScaleType(ImageView.ScaleType.CENTER_CROP);



                        rowOfList.add(btn);


                        row.addView(btn);
                    }

                    map.add(rowOfList);
                    table.addView(row);
                }

                mainContainer.addView(table);

什么可能导致更改ImageButtons的背景颜色？谢谢你！