试图显示到另一个类的视图

Question

所以当我尝试在屏幕上显示一些文本时，我会收到一个错误，我将在下面发布。将显示的此文本假定实际显示一个变量。它将显示玩家获得了多少点。很久以前，我从互联网上走了一条路。它可以编译，但我收到很多 LogCat 错误。这是我试图显示文本的主要类。

    public class Main extends Activity {
    DrawingView v;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);


        LinearLayout layout1 = new LinearLayout (this);
        FrameLayout game = new FrameLayout(this);
        DrawingView v = new DrawingView (this);

        TextView myText = new TextView(this);

        Button redCircle = new Button(this);



        redCircle.setWidth(300);
        redCircle.setText(DrawingView.addPoints);


        layout1.addView(myText);
        layout1.addView(redCircle); 
        redCircle.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));

        game.addView(myText);
        game.addView(v);
        game.addView(layout1);
        setContentView(v);
        //redCircle.setOnClickListener((OnClickListener) this);
    }
    public void onClick(View v) {
        Intent intent = new Intent(this, Main.class);
            startActivity(intent);

        // re-starts this activity from game-view. add this.finish(); to remove from stack
   }

    @Override
    public boolean onCreateOptionsMenu(Menu menu){
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }



}

这是我得到的 LogCat 错误。请不要投反对票，这个问题的描述非常详细，几乎没有语法错误。我知道你们所有的网络巨魔，纳粹会尽你最大的努力去做你最擅长的事情。

    04-20 01:51:42.998: E/AndroidRuntime(3154): FATAL EXCEPTION: main
04-20 01:51:42.998: E/AndroidRuntime(3154): Process: com.Tripps.thesimplegame, PID: 3154
04-20 01:51:42.998: E/AndroidRuntime(3154): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.Tripps.thesimplegame/com.Tripps.thesimplegame.Main}: android.content.res.Resources$NotFoundException: String resource ID #0x0
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.app.ActivityThread.access$800(ActivityThread.java:144)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.os.Handler.dispatchMessage(Handler.java:102)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.os.Looper.loop(Looper.java:135)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.app.ActivityThread.main(ActivityThread.java:5221)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at java.lang.reflect.Method.invoke(Native Method)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at java.lang.reflect.Method.invoke(Method.java:372)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
04-20 01:51:42.998: E/AndroidRuntime(3154): Caused by: android.content.res.Resources$NotFoundException: String resource ID #0x0
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.content.res.Resources.getText(Resources.java:274)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.widget.TextView.setText(TextView.java:4122)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at com.Tripps.thesimplegame.Main.onCreate(Main.java:38)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.app.Activity.performCreate(Activity.java:5933)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
04-20 01:51:42.998: E/AndroidRuntime(3154):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
04-20 01:51:42.998: E/AndroidRuntime(3154):     ... 10 more

这里有另外一门课可能会很有帮助，也可能会让人很困惑

public DrawingView(Context context) {
        super(context);
        // TODO Auto-generated constructor stub

    }
    RectF rectf = new RectF(0, 0, 200, 0);

    private static final int w = 100;
    public static int lastColor = Color.BLACK;
    private final Random random = new Random();
    private final Paint paint = new Paint();
    private final int radius = 230;
    private final Handler handler = new Handler();
    public static int redColor = Color.RED;
    public static int greenColor = Color.GREEN;
    int randomWidth = 0;
    int randomHeight = 0;
    public static int addPoints = 0;

     //TextView myTextView = new TextView(this);



     //redCircle.setWidth(300);
     //redCircle.setText("Start Game");


    private final Runnable updateCircle = new Runnable() {
        @Override 
        public void run() {
            lastColor = random.nextInt(2) == 1 ? redColor : greenColor;
            paint.setColor(lastColor);
            invalidate();
            handler.postDelayed(this, 1000);

        }
    };

    @Override 
    protected void onAttachedToWindow() {
        super.onAttachedToWindow();
        handler.post(updateCircle);
    }

    @Override 
    protected void onDetachedFromWindow() {
        super.onDetachedFromWindow();
        handler.removeCallbacks(updateCircle);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        // your other stuff here
        if(random == null){
            randomWidth =(int) (random.nextInt(Math.abs(getWidth()-radius/2)) + radius/2f);
            randomHeight = (random.nextInt((int)Math.abs((getHeight()-radius/2 + radius/2f))));
        }else {
            randomWidth =(int) (random.nextInt(Math.abs(getWidth()-radius/2)) + radius/2f);
            randomHeight = (random.nextInt((int)Math.abs((getHeight()-radius/2 + radius/2f))));
        }

        canvas.drawCircle(randomWidth, randomHeight + radius/2f, radius, paint);
    }

    public boolean onTouch(View v, MotionEvent event) {
   int x = (int) event.getX();
   int y = (int) event.getY();
   if(isInsideCircle(x, y) ==  true){
      //Do your things here
       if(redColor == lastColor){
          Intent i = new Intent(v.getContext(), YouFailed.class);
          v.getContext().startActivity(i);
       } else {
           addPoints++;
       }
   }else {

   }
   return true;
}

public boolean isInsideCircle(int x, int y){
  if ((((x - randomWidth)*(x - randomWidth)) + ((y - randomHeight)*(y - randomHeight))) < ((radius)*(radius)))
    return true;
  return false;    
}











}

Answer 1

错误在

int w = getResources().getInteger(Color.RED);

getInteger() 需要 res 值。 Color.RED 的值 0xffff0000 在 res 中找不到。因此出现错误。

Color.RED 已经是一个整数。您的资源值也是整数。因此，当它试图查找值为Color.RED 或0xffff0000 的资源时，它会出错，因为不存在这样的资源。

从您的代码来看，您似乎没有使用 XML 来设置布局。所以你使用的方式

int w = getResources().getInteger(Color.RED);
Button redCircle = (Button) findViewById(w);

似乎不正确。因为您的布局没有任何此类对象。您应该只创建一个新按钮。

Button redCircle = new Button(context);

并将其添加到布局中。

还有，

redCircle.setText(DrawingView.addPoints);

setText() 需要字符串或char[]。如果addPoints 不是字符串，您也应该更改它。您还可以使用您应该在 res/values 文件夹中定义的 R.string.some_string 传递一些 res 值。只是为了演示，改成redCicle.setText("Red Circle");

DrawingView.addPoints 也是整数。因此，当您传递redCircle.setText(DrawingView.addPoints); 时，编译器假定您传递了一些res 值，因为它们是基于整数映射的。在这里，addPoints 的值似乎为 0，因此编译器会查找映射值为 0 的资源，但该资源未找到，因此会抛出错误 android.content.res.Resources$NotFoundException: String resource ID #0x0。

TL;DR : Resource 值是基于整数映射的。 setText()、findViewById()、getResources().getInteger() 等需要一个映射到该特定资源的整数。如果您传递了一些随机整数（错误地），它将寻找该资源，因为编译器是愚蠢的（也许。也许不是。），并且在找不到资源时会抛出异常。

Answer 2

canvas.drawText("Score: " + addPoints, 120, 300, paint);

如果其他人有这个问题，这是正确的方法！