小编Ok-*_*lex的帖子

我有一个页面:http://f1u.org/competitions

有3个表.我不明白为什么他们都有双边界.

请帮我理解.

我需要覆盖onMeasure方法,但在尝试覆盖时我得到错误: The method OnMeasure(int, int) of type DrawLnClass.DrawLn must override a superclass method

这是我的代码:

public class DrawLnClass extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(new DrawLn(this));
    }
    public class DrawLn extends View {

        Paint _paint;
        int _height;
        int _width;
        Bitmap _bitmap;
        Canvas _canvas;
        Point[] xLine;
        Point[] yLine;

        public DrawLn(Context context) {
            super(context);
            _paint = new Paint();
            _paint.setColor(Color.CYAN);
            _paint.setStyle(Paint.Style.STROKE);
        }

        @Override
        protected void OnMeasure(int widthMeasureSpec, int heightMeasureSpec)
        {
            //super.onMeasure(widthMeasureSpec, heightMeasureSpec);
            _width = View.MeasureSpec.getSize(widthMeasureSpec);
            _height = View.MeasureSpec.getSize(heightMeasureSpec); …

我试图将exp(x)函数扩展到Taylor系列.这是代码:

double CalcExp(){
double eps = 0.0000000000000000001;
double elem = 1.0;
double sum = 0.0;
int i = 1;
sum = 0.0;
do {
    sum += elem;
    elem *= x / i;
    i++;
} while (elem >= eps);
return sum;

}

问题是当我输入大X或负X时我的程序崩溃了.当我像"0.00000000001"那样输入X时,结果是-1.

需要建议.感谢帮助.

请帮忙.我可以重启AsyncTask.每次第二次调用updatePoi()时,应用程序崩溃.

这是我的代码:

1. 我正在检查任务的状态并设置取消(true).

   public void updatePoi() {
       //new RefreshMapTask().execute();
       if (refreshMapTask.getStatus() == AsyncTask.Status.RUNNING || 
           refreshMapTask.getStatus() == AsyncTask.Status.PENDING) {
               refreshMapTask.cancel(true);
           }
           refreshMapTask.execute();
       }
   }
   

   Run Code Online (Sandbox Code Playgroud)

2. 这是我的AsyncTask.在doInBackground我写了一个休息.

   private class RefreshMapTask extends AsyncTask<Void, Void, Void> {
       @Override
       protected void onPreExecute() {
           super.onPreExecute();
           getMapView().getOverlays().clear();
           myPoiOverlay.clear();
           exitOverlay.clear();
       }
   
   
       @Override
       protected Void doInBackground(Void... voids) {
           Application app = (Application)getApplication();
           Log.d(TAG, "exits count = " + app.getExits().size());
   
           GeoPoint pointToNavigate = null;
   
           for (Exit exit : app.getExits()) {
   
               for (Poi poi : exit.getPoi()) {
                   if (isCancelled()){
                       break;
                   }
                   //some …

   Run Code Online (Sandbox Code Playgroud)

我在页面上有很多带有不同ID的复选框.

我想在每次选中或取消选中任何复选框时更改图片...

请告诉我该怎么做..