java - 在Android中将方法从Void更改为Return？

Question

我正在创建一个游戏，在其中绘制一条从 RelativeLayout 的中心 x,y 坐标开始的路径。我正在获取 x,y 坐标，但我不知道如何使用 getNumbers() 方法将坐标传递到路径绘图类中。我在 onCreate 中得到了这一点:

getNumbers();
path_em = new PathEM(this, xTint, yTint);
gBoard_RL.addView(path_em);
root_RL.addView(gBoard_RL);

这里是getNumbers():

    public void getNumbers() {
    gBoard_RL.getViewTreeObserver().addOnGlobalLayoutListener(NumbersoGLL);
}
OnGlobalLayoutListener NumbersoGLL = new OnGlobalLayoutListener() {
    @Override
    public void onGlobalLayout() {

        xRLWInt = gBoard_RL.getWidth() / 2;
        yRLHInt = gBoard_RL.getHeight() / 2;
        xTint = gBoard_RL.getLeft() + xRLWInt;
        yTint = gBoard_RL.getTop() + yRLHInt;   
    }
};

我想我必须重写 getNumbers() ，这样它就不是空的，而是返回 xTint 和 yTint，对吧？我不知道该怎么做，因为 public void onGlobalLayout() 无法更改为传递 int，当我尝试时，我收到一条错误，指出它必须为 void。

所以基本上，我想做的是在 Game3 类的 onCreate 中，我需要获取中心坐标整数，然后将它们传递到我的路径绘图中类(class)。这是整个 Game 3 类:

public class Game3 extends Activity {
PathEM path_em;
RelativeLayout root_RL, gBoard_RL, startTimer_RL;
LayoutParams root_LP, startTimer_LP, gBoardInfo_LP, gBoard_LP, rootStartTimer_LP;
LayoutInflater LayInf = null;
View root_VUE, gBoardInfo_VUE;
TextView gameScore_TV, gameTime_TV, readyCD_TV;
FrameLayout root_FrameL;
int xScrInt, yScrInt, xRLWInt, yRLHInt, xTint, yTint;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    overridePendingTransition(R.anim.cutin, R.anim.cutout);


    // -- Create Root Layout
    root_RL = new RelativeLayout(this);
    root_LP = new RelativeLayout.LayoutParams(
            RelativeLayout.LayoutParams.MATCH_PARENT,
            RelativeLayout.LayoutParams.MATCH_PARENT);
    root_RL.setId(1);
    root_RL.setBackgroundColor(Color.WHITE);
    root_RL.setLayoutParams(root_LP);
    // --- END Create Root Layout

    // --- Create GameBoard
    LayInf = (LayoutInflater) getApplicationContext().getSystemService(
            Context.LAYOUT_INFLATER_SERVICE);
    gBoardInfo_VUE = LayInf.inflate(R.layout.game1_info, null);
    gBoardInfo_LP = new LayoutParams(LayoutParams.MATCH_PARENT,
            LayoutParams.WRAP_CONTENT);
    gBoardInfo_LP.addRule(RelativeLayout.ALIGN_PARENT_TOP,
            RelativeLayout.TRUE);
    gBoardInfo_VUE.setId(2);
    gBoardInfo_VUE.setLayoutParams(gBoardInfo_LP);
    gameTime_TV = (TextView) gBoardInfo_VUE
            .findViewById(R.id.game1_timeValue2_TV);
    gameScore_TV = (TextView) gBoardInfo_VUE
            .findViewById(R.id.game1_scoreValue2_TV);
    root_RL.addView(gBoardInfo_VUE);

    gBoard_RL = new RelativeLayout(this);
    gBoard_LP = new RelativeLayout.LayoutParams(
            RelativeLayout.LayoutParams.MATCH_PARENT,
            RelativeLayout.LayoutParams.MATCH_PARENT);
    gBoard_LP.addRule(RelativeLayout.BELOW, gBoardInfo_VUE.getId());
    gBoard_LP.setMargins(10, 10, 10, 10);
    gBoard_RL.setLayoutParams(gBoard_LP);
    gBoard_RL.setBackgroundColor(Color.BLUE);

    //--- add stuff here
    getNumbers();
    path_em = new PathEM(this, xTint, yTint);
    gBoard_RL.addView(path_em);
    root_RL.addView(gBoard_RL);

    root_FrameL = new FrameLayout(this);
    root_FrameL.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT,
            LayoutParams.MATCH_PARENT));
    root_FrameL.addView(root_RL);
    setContentView(root_FrameL);
    // --- END Create GameBoard

}//--- END onCreate


public void getNumbers() {
    gBoard_RL.getViewTreeObserver().addOnGlobalLayoutListener(NumbersoGLL);
}
OnGlobalLayoutListener NumbersoGLL = new OnGlobalLayoutListener() {
    @Override
    public void onGlobalLayout() {

        xRLWInt = gBoard_RL.getWidth() / 2;
        yRLHInt = gBoard_RL.getHeight() / 2;
        xTint = gBoard_RL.getLeft() + xRLWInt;
        yTint = gBoard_RL.getTop() + yRLHInt;   
    }
};


//--- PathEM Class
public class PathEM extends View {

    Paint paint = new Paint();
    Path path = new Path();

    public PathEM(Context context, int xTint, int yTint){
        super(context);
    }

    Pt[] thePath = { new Pt(xTint, yTint),
            new Pt(200, 200),
            new Pt(200, 500),
            new Pt(400, 500)
    };

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        paint.setColor(Color.GREEN);
        paint.setStrokeWidth(7);
        paint.setStyle(Paint.Style.STROKE);
        path.moveTo(thePath[0].x, thePath[0].y);
        for (int i = 1; i < thePath.length; i++) {
            path.lineTo(thePath[i].x, thePath[i].y);
        }
        canvas.drawPath(path, paint);
    }// --- END onDraw

    class Pt {
        float x, y;

        Pt(float _x, float _y) {
            x = _x;
            y = _y;
        }
    }
}
}

Answer 1

您应该将代码放在 onGlobalLayout() 方法中初始化 PathEM 对象的位置。 像这样:

OnGlobalLayoutListener NumbersoGLL = new OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {

    xRLWInt = gBoard_RL.getWidth() / 2;
    yRLHInt = gBoard_RL.getHeight() / 2;
    xTint = gBoard_RL.getLeft() + xRLWInt;
    yTint = gBoard_RL.getTop() + yRLHInt;   

    path_em = new PathEM(this, xTint, yTint);
    gBoard_RL.addView(path_em);
    root_RL.addView(gBoard_RL);
  }
};