我开始制作一个简单的Android游戏（Tetris），但我无法在屏幕的下部进行绘图，而屏幕下部具有我目前在上面绘制基本形状的SurfaceView。当我尝试运行程序时，除非setContentView（在我的主要活动中）仅设置为SurfaceView对象，否则形状不会绘制。当我将内容视图设置为整个主要活动时，它将显示所有初始视图，但不会绘制形状。运行线程以在SurfaceView上绘制形状时，由于Canvas对象为空，它从不执行绘制。我只是想让我的活动在顶部具有几个TextView对象以及可以在上面绘制对象的SurfaceView。感谢您的帮助。
MainActivity onCreate：
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
在线程中运行方法：
public void run()
{
SurfaceHolder sh = bv.getHolder();
while(!Thread.interrupted())
{
Canvas c = sh.lockCanvas();
try
{
synchronized(sh)
{
bv.draw();
}
}
catch(Exception e)
{
}
finally
{
if(c != null)
{
sh.unlockCanvasAndPost(c);
}
}
try
{
Thread.sleep(1);
}
catch(InterruptedException e)
{
return;
}
}
}
自定义SurfaceView对象：
public class BoardView extends SurfaceView implements SurfaceHolder.Callback {
private float x = 0, y = 0;
private Paint paint = null;
private Timer timer = null;
TetrisThread th;
public BoardView(Context context) {
super(context);
paint = new Paint();
paint.setColor(Color.RED);
this.setZOrderOnTop(true);
getHolder().addCallback(this);
setFocusable(true);
}
public BoardView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public BoardView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public void draw() {
Canvas canvas = getHolder().lockCanvas();
canvas.drawColor(Color.WHITE);
canvas.save();
canvas.translate(x, y);
canvas.drawRect(850, 850, 950, 950, paint);
canvas.restore();
getHolder().unlockCanvasAndPost(canvas);
}
public void surfaceCreated(SurfaceHolder holder)
{
TetrisThread t = new TetrisThread(this);
t.start();
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height)
{
}
@Override
public void surfaceDestroyed(SurfaceHolder holder)
{
th.interrupt();
}
@Override
public boolean onTouchEvent(MotionEvent e)
{
return true;
}
}
主要活动XML
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/frame">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="20dp"
android:layout_marginTop="10dp"
android:layout_marginEnd="16dp"
android:layout_marginBottom="9dp"
android:text="Tetris"
android:textAppearance="@style/TextAppearance.AppCompat.Medium"
android:textColor="#03A9F4"
android:textSize="26sp"
android:textStyle="bold"
android:typeface="normal" />
<TextView
android:id="@+id/scoreheader"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="350dp"
android:layout_marginTop="0dp"
android:layout_marginEnd="16dp"
android:layout_marginBottom="9dp"
android:text="Score"
android:textAppearance="@style/TextAppearance.AppCompat.Medium"
android:textColor="#000000"
android:textSize="16sp"
android:textStyle= "bold"
android:typeface="normal" />
<TextView
android:id="@+id/score"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="354dp"
android:layout_marginTop="20dp"
android:layout_marginEnd="16dp"
android:layout_marginBottom="9dp"
android:text="XX"
android:textAppearance="@style/TextAppearance.AppCompat.Medium"
android:textColor="#000000"
android:textSize="25sp"
android:textStyle= "normal"
android:typeface="normal" />
<!--<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="300dp"
android:layout_marginTop="10dp"
android:layout_marginEnd="16dp"
android:layout_marginBottom="9dp"
android:text="New Game"
android:textSize="12sp" /> -->
<com.example.tetris.BoardView
android:id="@+id/board"
android:layout_width="match_parent"
android:layout_height="680dp"
android:layout_marginStart="0dp"
android:layout_marginTop="70dp"
android:background="#000fff" />
</FrameLayout>