在我的应用程序中,我需要使用位图和drawCircle()方法绘制圆圈.
一切都运行正常,直到Android 6.0.
它仍然在所有以前的版本上绘制圆圈,但在6.0上使用应用程序时绘制矩形.但是,如果我将其更改为填充,则会在api 22和api 23中绘制一个圆圈.
任何人都有同样的问题或任何想法为什么会这样？
这是源代码和屏幕截图(左侧是API 23上运行的应用程序,右侧是API 22). same app on different api’s
public final class Circle1View extends View {
private float xCenter,yCenter;
private Bitmap grid = null;
public Circle1View (Context context) {
super(context);
init();
}
private void init() {
setLayerType(View.LAYER_TYPE_SOFTWARE,null);
}
@Override
protected void onDraw(Canvas canvas) {
int w = getWidth();
int h = getHeight();
xCenter = w / 2;
yCenter = h / 2;
drawBitmaps(w,h);
canvas.translate(xCenter,yCenter);
canvas.scale(xCenter,yCenter);
canvas.drawBitmap(grid,null,new RectF(-1,-1,1,1),null);
}
private void drawBitmaps(int w,int h) {
grid = Bitmap.createBitmap(w,h,Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas();
canvas.translate(xCenter,yCenter);
Paint gridPaint = new Paint();
gridPaint.setStrokeWidth(0.01f);
// Works with FILL
// gridPaint.setStyle(Paint.Style.FILL);
gridPaint.setStyle(Paint.Style.STROKE);
canvas.setBitmap(grid);
canvas.drawCircle(0,0.5f,gridPaint);
}
}
解决方法
我认为这与你做的缩放和翻译有关.想象一下,绘制的圆是如此之小,它只需要4个像素.将其放大到最大尺寸时,在这些像素之间留下4条直线.
当我将笔划宽度更改为0.04f时,问题就消失了.我建议您直接使用提供的Canvas来简化代码：
@Override
protected void onDraw(Canvas canvas) {
int w = getWidth();
int h = getHeight();
xCenter = w / 2;
yCenter = h / 2;
Paint gridPaint = new Paint();
gridPaint.setStrokeWidth(1f);
gridPaint.setStyle(Paint.Style.STROKE);
canvas.drawCircle(xCenter,yCenter,w/4,gridPaint);
}
关于API级别之间差异的问题：Marshmallow引入了drawBitmap()的更改.您可以查看Lollipop和Marshmallow的相应源代码.
