我正在尝试制作一个与常规WebView完全相同的自定义WebView,只是它具有圆角。圆角必须透明,因为我想将此WebView放在对话框中。
我想像这样制作自定义类:
public class RoundedWebView extends WebView
{
private Context context;
private int width;
private int height;
public RoundedWebView(Context context)
{
super(context);
initialize(context);
}
public RoundedWebView(Context context, AttributeSet attrs)
{
super(context, attrs);
initialize(context);
}
public RoundedWebView(Context context, AttributeSet attrs, int defStyleAttr)
{
super(context, attrs, defStyleAttr);
initialize(context);
}
private void initialize(Context context)
{
this.context = context;
}
// This method gets called when the view first loads, and also whenever the
// view changes. Use this opportunity to save the view's width and height.
@Override protected void onSizeChanged(int newWidth, int newHeight, int oldWidth, int oldHeight)
{
this.width = newWidth;
this.height = newHeight;
super.onSizeChanged(newWidth, newHeight, oldWidth, oldHeight);
}
@Override protected void onDraw(Canvas canvas)
{
int radius = Utilities.dpToPx(context, 5);
Path clipPath = new Path();
clipPath.addRoundRect(new RectF(0, 0, width, height), radius, radius, Path.Direction.CW);
canvas.clipPath(clipPath);
super.onDraw(canvas);
}
}
并且这种实现方式在大多数情况下都有效。但是,一旦url完成加载并在屏幕上显示出来,我就失去了WebView的圆角。知道发生了什么吗?
这是我找到的解决方案。在我的onDraw()方法中,我创建了一个倒置,填充,圆角的矩形,然后使用Porter Duff Xfer模式从屏幕上“清除”该区域。这给我留下了一个具有很好的倾斜边缘的WebView,包括WebView完成加载URL的情况。
public class RoundedWebView extends WebView
{
private Context context;
private int width;
private int height;
private int radius;
public RoundedWebView(Context context)
{
super(context);
initialize(context);
}
public RoundedWebView(Context context, AttributeSet attrs)
{
super(context, attrs);
initialize(context);
}
public RoundedWebView(Context context, AttributeSet attrs, int defStyleAttr)
{
super(context, attrs, defStyleAttr);
initialize(context);
}
private void initialize(Context context)
{
this.context = context;
}
// This method gets called when the view first loads, and also whenever the
// view changes. Use this opportunity to save the view's width and height.
@Override protected void onSizeChanged(int newWidth, int newHeight, int oldWidth, int oldHeight)
{
super.onSizeChanged(newWidth, newHeight, oldWidth, oldHeight);
width = newWidth;
height = newHeight;
radius = Utilities.dpToPx(context, 5);
}
@Override protected void onDraw(Canvas canvas)
{
super.onDraw(canvas);
Path path = new Path();
path.setFillType(Path.FillType.INVERSE_WINDING);
path.addRoundRect(new RectF(0, getScrollY(), width, getScrollY() + height), radius, radius, Path.Direction.CW);
canvas.drawPath(path, createPorterDuffClearPaint());
}
private Paint createPorterDuffClearPaint()
{
Paint paint = new Paint();
paint.setColor(Color.TRANSPARENT);
paint.setStyle(Style.FILL);
paint.setAntiAlias(true);
paint.setXfermode(new PorterDuffXfermode(Mode.CLEAR));
return paint;
}
}
我添加了此类的改进的Kotlin版本。就像魅力一样,非常感谢@Luke!