Question

我目前正在构建一个Android应用程序，该应用程序在连接到信标时会显示信息。我需要根据onBeaconServiceConnect()事件来更新文本和位置。由于初始活动已经由onDraw方法绘制，因此我不能依靠它进行更新。

我试图向Activity添加一个TextView并使Canvas对象公开，但都没有帮助我。

CustomView：

public class CustomView extends View {


private Rect rectangle,
            positionRect;

    private Paint paint,
            paintPoint,
            textPaint,
            positionPaint;

public CustomView(Context context) {
        super(context);
        int x = 100, y= 100, sideLength = 100;

        // create a rectangle that we'll draw later
        rectangle = new Rect(x, y, sideLength, sideLength);
        positionRect = new Rect(400, 540, 360, 590);

        // create the Paint and set its color
        paint = new Paint();
        paint.setColor(Color.GRAY);

        paintPoint = new Paint();
        paintPoint.setColor(Color.RED);

        textPaint = new Paint();
        textPaint.setColor(Color.BLACK);
        textPaint.setTextSize(40);

        positionPaint = new Paint();
        positionPaint.setColor(Color.GREEN);

    }

@Override
protected void onDraw(Canvas canvas) {
        canvas.drawColor(Color.WHITE);
        canvas.drawRect(rectangle, paint);


        double[][] positions = new double[][] { { 0, 0 }, { 0, 10 }, { 10, 10 }, { 10, 0 } };
        double[] distances = new double[] { 8.06, 13.97, 23.32, 15.31 };

        int amountOfBeacons = positions.length;

        for(int i = 0; i < amountOfBeacons; i++){
            if (i == 0){
                canvas.drawCircle(100,100, 20, paintPoint);
                canvas.drawText("Beacon 1", 100, 60, textPaint);
            }

            else if (i == 1){
                canvas.drawCircle(100,1000, 20, paintPoint);
                canvas.drawText("Beacon 2", 100, 1060, textPaint);
            }

            else if (i == 2){
                canvas.drawCircle(1000, 1000, 20, paintPoint);
                canvas.drawText("Beacon 3", 900, 1060, textPaint);
            }

            else if (i == 3){
                canvas.drawCircle(1000,100, 20, paintPoint);
                canvas.drawText("Beacon 4", 900, 60, textPaint);
            }
        }


        canvas.drawRect(positionRect, positionPaint);
        canvas.drawText("my position", 350, 650, textPaint);

        canvas.drawText(amountOfBeacons + " beacons are currently active", 100, 1200, textPaint);
        String  distanceString =  "";
        for (int i = 0; i < distances.length; i++) {
            distanceString += String.valueOf(distances[i] + "m ");

        }
    }
}

MainActivity：

public class MainActivity extends Activity implements BeaconConsumer{

//initialize stuff

@Override
protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        customView = new CustomView(this);
        setContentView(customView);

        checkPermissions(MainActivity.this, this);

//some beacon logic

    }

@Override
protected void onDestroy() {
        super.onDestroy();
        beaconManager.unbind(this);
    }

@Override
public void onBeaconServiceConnect() {
        beaconManager.removeAllRangeNotifiers();
        beaconManager.addRangeNotifier(new RangeNotifier() {
            @Override
            public void didRangeBeaconsInRegion(Collection<Beacon> beacons, Region region) {
                if (beacons.size() > 0) {
                    Log.i(TAG, "The first beacon I see is about "+beacons.iterator().next().getDistance()+" meters away.");
                }


//Need to change text that was set in the onDraw Method of CustomView here
//Also need to change the location of a rect that was set in the onDraw here


            }
        });

        try {
            beaconManager.startRangingBeaconsInRegion(new Region("myRangingUniqueId", null, null, null));
        } catch (RemoteException e) {    }
    }
}

我尝试过的每种方法都以错误结束或什么都没显示。我可以对逻辑的位置非常灵活。如果有帮助，它既可以在“活动”中又可以在“视图”中工作。

如何不依靠onDraw从Activity更新我的CustomView？

0 个答案: