我想使用来自外部设备的数组或实时绘图值中的样本值来绘制线条。我几乎得到了ans。但是画布从开始到终点都没有绘制速度。执行一些数据后画布几乎死得很慢。请建议我在提取方法中有什么问题...
public class WaveDrawing extends View {
public final Paint backgroundColor = new Paint(Paint.ANTI_ALIAS_FLAG);
public final Paint patientData = new Paint(Paint.ANTI_ALIAS_FLAG);
public final Paint patientDataRePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
int i = 0; //k = 36;
//graph point
int[] a = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 0, 0, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 26, 40, 44, 48, 50, -25, -20, -15, -10, -5, -0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, -50, -48, -46, -44, -42, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -7, -6, -6, -5, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 0
,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 0, 0, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 26, 40, 44, 48, 50, -25, -20, -15, -10, -5, -0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, -50, -48, -46, -44, -42, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -7, -6, -6, -5, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 0
,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 0, 0, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 26, 40, 44, 48, 50, -25, -20, -15, -10, -5, -0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, -50, -48, -46, -44, -42, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -7, -6, -6, -5, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 0
,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 0, 0, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 26, 40, 44, 48, 50, -25, -20, -15, -10, -5, -0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, -50, -48, -46, -44, -42, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -7, -6, -6, -5, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 0
,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 0, 0, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 26, 40, 44, 48, 50, -25, -20, -15, -10, -5, -0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, -50, -48, -46, -44, -42, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -7, -6, -6, -5, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 0
,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 0, 0, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 26, 40, 44, 48, 50, -25, -20, -15, -10, -5, -0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, -50, -48, -46, -44, -42, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -7, -6, -6, -5, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 0
,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 0, 0, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 26, 40, 44, 48, 50, -25, -20, -15, -10, -5, -0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, -50, -48, -46, -44, -42, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -7, -6, -6, -5, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 0
,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 0, 0, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 26, 40, 44, 48, 50, -25, -20, -15, -10, -5, -0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, -50, -48, -46, -44, -42, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -7, -6, -6, -5, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 0
,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 0, 0, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 26, 40, 44, 48, 50, -25, -20, -15, -10, -5, -0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, -50, -48, -46, -44, -42, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -7, -6, -6, -5, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 0
,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, 0, 0, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 26, 40, 44, 48, 50, -25, -20, -15, -10, -5, -0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48, 54, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 6, 6, 5, 5, 4, 4, 3, 3, 2, 2, 1, 1, -50, -48, -46, -44, -42, -40, -38, -36, -34, -32, -30, -28, -26, -24, -22, -20, -18, -16, -14, -12, -10, -8, -6, -4, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, -1, -2, -2, -3, -3, -4, -4, -5, -5, -6, -6, -7, -6, -6, -5, -5, -4, -4, -3, -3, -2, -2, -1, -1, 0, 0, 0, 0
};
//int pre, next;
public WaveDrawing(Context context) {
super(context);
init();
}
public WaveDrawing(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public WaveDrawing(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
public void init() {
// backgroundColor.setColor(Color.BLACK);
patientData.setColor(Color.GREEN);
patientDataRePaint.setColor(Color.WHITE);
patientData.setStrokeWidth(2);
}
@Override
public synchronized void onDraw(Canvas canvas) {
super.onDraw(canvas);
int widthIterator = 0;
//canvas.drawRect(0, 0, getWidth(), getHeight(), backgroundColor);
if (i != 0) {
for (int drawPulseIterator = 1; drawPulseIterator <= i; drawPulseIterator++) {
if (widthIterator > getWidth() ) {
widthIterator = 0;
// k = widthIterator;
} else {
widthIterator += 1;
}
canvas.drawRect(widthIterator, 0, widthIterator + 7, getHeight(), patientDataRePaint);
canvas.drawLine(widthIterator, (getHeight() / 2) - a[drawPulseIterator], widthIterator + 1, (getHeight() / 2) - a[drawPulseIterator - 1], patientData);
}
}
i++;
if (i == a.length) {
i = 1;
}
invalidate();
}
}
XML
<com.test.sample.wave.WaveDrawing
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
答案 0 :(得分：1)
在onDraw方法中，循环迭代次数增加。这导致每个传递渲染周期需要做更多工作的事实。您的动画也取决于设备性能。因此，对于功能更强大的设备，动画会更快。通常，使用onDraw()和invalidate()绘制动态图形 - 不好主意。出于这些目的，最好使用OpenGL ES。对于不同设备上的相同性能，动画最好在帧之间进行时间相关的渲染
答案 1 :(得分：0)
还有另一种方式。您可以在位图中绘制脉冲线。然后在主Canvas上绘制位图：
@Override
public synchronized void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (!mIsInited) {
int w = getWidth(), h = getHeight();
Bitmap.Config conf = Bitmap.Config.ARGB_8888;
mBitmap = Bitmap.createBitmap(w, h, conf);
mCanvas = new Canvas(mBitmap);
mCanvas.drawColor(Color.WHITE);
mIsInited = true;
}
if (i != 0) {
if (mWidthIterator > getWidth()) {
mWidthIterator = 0;
} else {
mWidthIterator += 1;
}
mCanvas.drawRect(mWidthIterator, 0, mWidthIterator + 7, getHeight(), patientDataRePaint);
mCanvas.drawLine(mWidthIterator, (getHeight() / 2) - a[i], mWidthIterator + 1, (getHeight() / 2) - a[i - 1], patientData);
}
canvas.drawBitmap(mBitmap, 0, 0, null);
i++;
if (i == a.length) {
i = 1;
mWidthIterator = 0;
mCanvas.drawColor(Color.WHITE);
}
invalidate();
}
另外，不要忘记将mWidthIterator，mCanvas和mBitmap作为实例变量。