下一個類是一個紅色三角形的視圖:Canvas.drawVertices(...)繪製任何東西
public class FreeStyleViewII extends View {
private final Paint paint = new Paint();
private final int[] colors = new int[] {
Color.RED,
Color.RED,
Color.RED,
0xFF000000, 0xFF000000, 0xFF000000
};
private final float[] verts = new float[] {
1f/2f * 200f, 1f/4f * 200f,
1f/4f * 200f, 3f/4f * 200f,
3f/4f * 200f, 3f/4f * 200f
};
private final Path path = new Path();
{
path.moveTo(1/2 * 200, 1/4 * 200);
path.lineTo(1/4 * 200, 3/4 * 200);
path.lineTo(3/4 * 200, 3/4 * 200);
path.lineTo(1/2 * 200, 1/4 * 200);
}
private final RectF bounds = new RectF();
public FreeStyleViewII(Context context) {
super(context);
}
public FreeStyleViewII(Context context, AttributeSet attrs) {
super(context, attrs);
}
public FreeStyleViewII(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
@Override
protected void onDraw(Canvas canvas) {
canvas.clipRect(bounds);
canvas.drawRGB(0, 0, 0);
paint.setStyle(Style.FILL);
paint.setColor(Color.RED);
// HERE. WHY DRAWVERTICES DOESN'T WORK BUT DRAWPATH DOES?...
canvas.drawVertices(Canvas.VertexMode.TRIANGLES, verts.length, verts, 0, null, 0, colors, 0, null, 0, 0, paint);
// canvas.drawPath(path, paint);
paint.setStyle(Style.STROKE);
paint.setColor(Color.LTGRAY);
canvas.drawLine(0, bounds.bottom/2, bounds.right, bounds.bottom/2, paint);
canvas.drawLine(bounds.right/2, 0, bounds.right/2, bounds.bottom, paint);
// Delay
try {
Thread.sleep(30);
} catch (InterruptedException e) { }
invalidate();
}
@Override
public void onSizeChanged(int w, int h, int oldW, int oldH) {
bounds.set(1, 1, w - 1, h - 1);
System.out.println(bounds.left + " " + bounds.top + " " + bounds.right + " " + bounds.bottom);
verts[0] = bounds.left + ((bounds.right - bounds.left) * (1f/2f));
verts[1] = bounds.top + ((bounds.bottom - bounds.top) * (1f/4f));
System.out.println(" Point: X ----> " + verts[0] + " | Y ----> " + verts[1]);
verts[2] = bounds.left + ((bounds.right - bounds.left) * (1f/4f));
verts[3] = bounds.top + ((bounds.bottom - bounds.top) * (3f/4f));
System.out.println(" Point: X ----> " + verts[2] + " | Y ----> " + verts[3]);
verts[4] = bounds.left + ((bounds.right - bounds.left) * (3f/4f));
verts[5] = bounds.top + ((bounds.bottom - bounds.top) * (3f/4f));
System.out.println(" Point: X ----> " + verts[4] + " | Y ----> " + verts[5]);
path.reset();
path.moveTo(verts[0], verts[1]);
path.lineTo(verts[2], verts[3]);
path.lineTo(verts[4], verts[5]);
path.lineTo(verts[0], verts[1]);
}
}
當我使用Canvas.drawPath方法,它工作正常。但是,如果我更改爲Canvas.drawVertices,它什麼也不畫。我已經檢查了Bug in Canvas.drawVertices? (with repro code and logcat)和Method drawVertices() didn't drawing anything on Android Canvas中的內容,但結果與我的情況相同。
我在VirtualBox(v 4.1.22)中使用AndroVM(v 4.1.1)進行測試。它可能是模擬器嗎?
有什麼想法?