您当前的位置: 我想做个android程序，类似于网上有一个通过摄像头在闪光灯常亮的帮助下，拍摄手指血流运动，从而在屏幕上显示心电图的程序。
我现在很烦恼的是，如何把画出来的心电图向左移动，而且执行速度要快，不要有闪动，诸位有什么比较好的建议和方法吗？
谢谢！
------解决方案--------------------
你可以去看看appdemo里os/Sensors。。他也是一个类似的东西。。
------解决方案--------------------
一个数组存个种点~画的时候把出现在屏幕上的点连起来就行了。比如说line(point1.x, point1.y, point2.x, point2.y)
------解决方案--------------------
代码格式弄错了，晕！
- Java code
private class GraphView extends View implements SensorListener {
private Bitmap mBitmap;
private Paint mPaint = new Paint();
private Canvas mCanvas = new Canvas();
private Path mPath = new Path();
private RectF mRect = new RectF();
private float mLastValues[] = new float[3 * 2];
private float mOrientationValues[] = new float[3];
private int mColors[] = new int[3 * 2];
private float mLastX;
private float mScale[] = new float[2];
private float mYOffset;
private float mMaxX;
private float mSpeed = 1.0f;
private float mWidth;
private float mHeight;
public GraphView(Context context) {
super(context);
mColors[0] = Color.argb(192, 255, 64, 64);
mColors[1] = Color.argb(192, 64, 128, 64);
mColors[2] = Color.argb(192, 64, 64, 255);
mColors[3] = Color.argb(192, 64, 255, 255);
mColors[4] = Color.argb(192, 128, 64, 128);
mColors[5] = Color.argb(192, 255, 255, 64);
mPaint.setFlags(Paint.ANTI_ALIAS_FLAG);
mRect.set(-0.5f, -0.5f, 0.5f, 0.5f);
mPath.arcTo(mRect, 0, 180);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
mBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.RGB_565);
mCanvas.setBitmap(mBitmap);
mCanvas.drawColor(0xFFFFFFFF);
mYOffset = h * 0.5f;
mScale[0] = -(h * 0.5f * (1.0f / (SensorManager.STANDARD_GRAVITY * 2)));
mScale[1] = -(h * 0.5f * (1.0f / (SensorManager.MAGNETIC_FIELD_EARTH_MAX)));
mWidth = w;
mHeight = h;
if (mWidth < mHeight) {
mMaxX = w;
} else {
mMaxX = w - 50;
}
mLastX = mMaxX;
super.onSizeChanged(w, h, oldw, oldh);
}
@Override
protected void onDraw(Canvas canvas) {
synchronized (this) {
if (mBitmap != null) {
final Paint paint = mPaint;
final Path path = mPath;
final int outer = 0xFFC0C0C0;
final int inner = 0xFFff7010;
if (mLastX >= mMaxX) {
mLastX = 0;
final Canvas cavas = mCanvas;
final float yoffset = mYOffset;
final float maxx = mMaxX;
final float oneG = SensorManager.STANDARD_GRAVITY
* mScale[0];
paint.setColor(0xFFAAAAAA);
cavas.drawColor(0xFFFFFFFF);
cavas.drawLine(0, yoffset, maxx, yoffset, paint);
cavas.drawLine(0, yoffset + oneG, maxx, yoffset + oneG,
paint);
cavas.drawLine(0, yoffset - oneG, maxx, yoffset - oneG,
paint);
}
canvas.drawBitmap(mBitmap, 0, 0, null);
float[] values = mOrientationValues;
if (mWidth < mHeight) {
float w0 = mWidth * 0.333333f;
float w = w0 - 32;
float x = w0 * 0.5f;
for (int i = 0; i < 3; i++) {
canvas.save(Canvas.MATRIX_SAVE_FLAG);
canvas.translate(x, w * 0.5f + 4.0f);
canvas.save(Canvas.MATRIX_SAVE_FLAG);
paint.setColor(outer);
canvas.scale(w, w);
canvas.drawOval(mRect, paint);
canvas.restore();
canvas.scale(w - 5, w - 5);
paint.setColor(inner);
canvas.rotate(-values[i]);
canvas.drawPath(path, paint);
canvas.restore();
x += w0;
}
} else {
float h0 = mHeight * 0.333333f;
float h = h0 - 32;
float y = h0 * 0.5f;
for (int i = 0; i < 3; i++) {
canvas.save(Canvas.MATRIX_SAVE_FLAG);
canvas.translate(mWidth - (h * 0.5f + 4.0f), y);
canvas.save(Canvas.MATRIX_SAVE_FLAG);
paint.setColor(outer);
canvas.scale(h, h);
canvas.drawOval(mRect, paint);
canvas.restore();
canvas.scale(h - 5, h - 5);
paint.setColor(inner);
canvas.rotate(-values[i]);
canvas.drawPath(path, paint);
canvas.restore();
y += h0;
}
}
}
}
}
public void onSensorChanged(int sensor, float[] values) {
// Log.d(TAG, "sensor: " + sensor + ", x: " + values[0] + ", y: " +
// values[1] + ", z: " + values[2]);
synchronized (this) {
if (mBitmap != null) {
final Canvas canvas = mCanvas;
final Paint paint = mPaint;
if (sensor == SensorManager.SENSOR_ORIENTATION) {
for (int i = 0; i < 3; i++) {
mOrientationValues[i] = values[i];
}
} else {
float deltaX = mSpeed;
float newX = mLastX + deltaX;
int j = (sensor == SensorManager.SENSOR_MAGNETIC_FIELD) ? 1
: 0;
for (int i = 0; i < 3; i++) {
int k = i + j * 3;
final float v = mYOffset + values[i] * mScale[j];
paint.setColor(mColors[k]);
canvas.drawLine(mLastX, mLastValues[k], newX, v,
paint);
mLastValues[k] = v;
}
if (sensor == SensorManager.SENSOR_MAGNETIC_FIELD)
mLastX += mSpeed;
}
invalidate();
}
}
}
public void onAccuracyChanged(int sensor, int accuracy) {
// TODO Auto-generated method stub
}
}