LinearLayout未显示创建的网格

Question

ID为“linBoardGame”的LinearLayout未显示创建的网格。 网格中的每个单元格都使用可绘制的“cell_bg.xml”创建。 代码编译时没有任何错误，但LinearLayout“linBoardGame”为空白，不显示任何网格。

MainActivity.java：

public class MainActivity extends AppCompatActivity {

    //board size
    final static int maxN=15;

    private Context context;
    //image view cells array
    private ImageView[][] ivCell = new ImageView[maxN][maxN];

    //0 is empty, 1 is player, 2 is bot, 3 is background
    private Drawable[] drawCell = new Drawable[4];

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        context = this;
        loadResources();
        designBoardGame();
    }

    private void loadResources() {
        drawCell[3]=context.getResources().getDrawable(R.drawable.cell_bg);
        drawCell[0] = null;
        drawCell[1] = context.getResources().getDrawable(R.drawable.circle);
        drawCell[2] = context.getResources().getDrawable(R.drawable.circle);
    }

    @SuppressLint("NewApi")
    private void designBoardGame() {
        //create layoutparams to optimize size of cell

        int sizeofCell = Math.round(ScreenWidth()/maxN);
        LinearLayout.LayoutParams lpRow = new LinearLayout.LayoutParams(sizeofCell*maxN, sizeofCell);
        LinearLayout.LayoutParams lpCell = new LinearLayout.LayoutParams(sizeofCell, sizeofCell);

        LinearLayout linBoardGame = (LinearLayout)findViewById(R.id.linBoardGame);

        //create cells
        for(int i=0;i<maxN;i++){

            LinearLayout linRow = new LinearLayout(context);
            //make a row
            for(int j=0; j<maxN; j++){
                ivCell[i][j] = new ImageView(context);
                //make a cell
                //need to set background default to cell
                //3 states of cell: empty(default), player, bot
                ivCell[i][j].setBackground(drawCell[3]);
                linRow.addView(ivCell[i][j], lpCell);
                Log.e("hello","hello");
            }
        }
    }

    private float ScreenWidth() {
        Resources resources = context.getResources();
        DisplayMetrics dm = resources.getDisplayMetrics();
        return dm.widthPixels;
    }
}

activity_main.xml文件：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <LinearLayout
        android:id="@+id/linMenu"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <Button
            android:id="@+id/btnPlay"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="2dp"
            android:background="@color/colorAccent"
            android:padding="20dp"
            android:text="Button" />

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_marginTop="2dp"
            android:orientation="horizontal">

            <TextView
                android:id="@+id/textView4"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@android:color/holo_blue_bright"
                android:text="Turn of:" />

            <TextView
                android:id="@+id/tvTurn"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:background="@android:color/holo_blue_dark"
                android:text="click new game to play" />
        </LinearLayout>

    </LinearLayout>

    <LinearLayout
        android:id="@+id/linBoardGame"
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:layout_marginTop="8dp"
        android:orientation="vertical"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/linMenu"></LinearLayout>
</android.support.constraint.ConstraintLayout>

cell_bg.xml：

<?xml version="1.0" encoding="utf-8"?>
<shape
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <corners android:radius="7dp"></corners>
    <solid android:color="@android:color/white"/>
</shape>

Answer 1

您正在创建ImageView并正确地将它们添加到每一行！ 但是，您还应该将行添加到linBoardGame权限;）

for (i in 0 until maxN) {
    for (j in 0 until maxN) {}

    // Right here I guess
    linBoardGame.addView(linRow, lpRow);
}

Answer 2

您忘记将动态创建的行布局linRow添加到主线性布局linBoardGame 。

LinearLayout linBoardGame =（LinearLayout）findViewById（R.id.linBoardGame）;

    //create cells
    for(int i=0;i<maxN;i++){

        LinearLayout linRow = new LinearLayout(context);
        //make a row
        for(int j=0; j<maxN; j++){
            ivCell[i][j] = new ImageView(context);
            //make a cell
            //need to set background default to cell
            //3 states of cell: empty(default), player, bot
            ivCell[i][j].setBackground(drawCell[3]);
            linRow.addView(ivCell[i][j], lpCell);
            Log.e("hello","hello");
        }
            //add created row to main board layout.
            linBoardGame.addView(linRow, new_layout_params);
    }