防止以后重复造轮子，直接这里搞个代码
本质上只要绘制圆角边框就行了，嗯，知道原理了，那代码还不简单？
淦，直接上代码
<declare-styleable name="OvalView">
<attr name="all_radius" format="dimension" />
<attr name="ul_radius" format="dimension" />
<attr name="ur_radius" format="dimension" />
<attr name="ll_radius" format="dimension" />
<attr name="lr_radius" format="dimension" />
<attr name="stroke_size" format="dimension" />
<attr name="stroke_color" format="color" />
<attr name="is_oval" format="boolean" />
<attr name="is_round_rectangle" format="boolean" />
</declare-styleable>public class CornerPlayView extends PlayerView {
/*圆角的半径，依次为左上角xy半径，右上角，右下角，左下角*/
//此处可根据自己需要修改大小
private float ul_radius;
private float ur_radius;
private float ll_radius;
private float lr_radius;
private float radius;
private float strokeSize;
private int strokeColor;
private boolean isAllRound = false;
private boolean isOval;
private boolean isRoundedRectangle = false;
public CornerPlayView(Context context) {
this(context, null);
}
public CornerPlayView(Context context, @Nullable AttributeSet attrs) {
this(context, attrs, 0);
}
public CornerPlayView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
// 获取属性集合 TypedArray
TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.OvalView);
// 获取属性
strokeColor = typedArray.getColor(R.styleable.OvalPlayerView_stroke_color_1, Color.TRANSPARENT);
strokeSize = typedArray.getDimension(R.styleable.OvalPlayerView_stroke_size_1, 0);
isOval = typedArray.getBoolean(R.styleable.OvalPlayerView_is_oval_1, false);
if (isOval)
return;
isRoundedRectangle = typedArray.getBoolean(R.styleable.OvalPlayerView_is_round_rectangle_1, false);
if (isRoundedRectangle)
return;
radius = typedArray.getDimension(R.styleable.OvalPlayerView_all_radius_1, 0);
if (radius != 0) {
isAllRound = true;
} else {
ul_radius = typedArray.getDimension(R.styleable.OvalPlayerView_ul_radius_1, 0);
ur_radius = typedArray.getDimension(R.styleable.OvalPlayerView_ur_radius_1, 0);
ll_radius = typedArray.getDimension(R.styleable.OvalPlayerView_ll_radius_1, 0);
lr_radius = typedArray.getDimension(R.styleable.OvalPlayerView_lr_radius_1, 0);
}
}
@Override
protected void onDraw(Canvas canvas) {
Path path = new Path();
int w = this.getWidth();
int h = this.getHeight();
/*向路径中添加圆角矩形。radii数组定义圆角矩形的四个圆角的x,y半径。radii长度必须为8*/
if (isOval)
path.addRoundRect(new RectF(0, 0, w, h), w / 2, h / 2, Path.Direction.CW);
else if (isRoundedRectangle) {
int s = Math.min(w, h);
path.addRoundRect(new RectF(0, 0, w, h), s / 2, s / 2, Path.Direction.CW);
} else if (isAllRound)
path.addRoundRect(new RectF(0, 0, w, h), radius, radius, Path.Direction.CW);
else
path.addRoundRect(new RectF(0, 0, w, h),
new float[]{ul_radius, ul_radius,
ur_radius, ur_radius,
lr_radius, lr_radius,
ll_radius, ll_radius,}, Path.Direction.CW);
canvas.clipPath(path);
super.onDraw(canvas);
if (strokeSize > 0) {
Paint paint = new Paint();
paint.setStrokeWidth(strokeSize);
paint.setColor(strokeColor);
paint.setStyle(Paint.Style.STROKE);
paint.setAntiAlias(true);
canvas.drawPath(path, paint);
}
}
@Override
protected void dispatchDraw(Canvas canvas) {
Path path = new Path();
int w = this.getWidth();
int h = this.getHeight();
/*向路径中添加圆角矩形。radii数组定义圆角矩形的四个圆角的x,y半径。radii长度必须为8*/
if (isOval)
path.addRoundRect(new RectF(0, 0, w, h), w / 2, h / 2, Path.Direction.CW);
else if (isRoundedRectangle) {
int s = Math.min(w, h);
path.addRoundRect(new RectF(0, 0, w, h), s / 2, s / 2, Path.Direction.CW);
} else if (isAllRound)
path.addRoundRect(new RectF(0, 0, w, h), radius, radius, Path.Direction.CW);
else
path.addRoundRect(new RectF(0, 0, w, h),
new float[]{ul_radius, ul_radius,
ur_radius, ur_radius,
lr_radius, lr_radius,
ll_radius, ll_radius,}, Path.Direction.CW);
if (getBackground() != null && w > 0 && h > 0) {
if (getBackground() instanceof ColorDrawable) {
Paint paint = new Paint();
ColorDrawable colorDrawable = (ColorDrawable) getBackground();
paint.setColor(colorDrawable.getColor());
paint.setAntiAlias(true);
canvas.drawPath(path, paint);
// Bitmap output = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
// Canvas canvas2 = new Canvas(output);
// canvas2.drawPath(path, paint);
// setBackground(new BitmapDrawable(output));
}
}
canvas.clipPath(path);
super.dispatchDraw(canvas);
if (isShowStroke && strokeSize > 0) {
Paint paint = new Paint();
paint.setStrokeWidth(strokeSize);
paint.setColor(strokeColor);
paint.setStyle(Paint.Style.STROKE);
paint.setAntiAlias(true);
canvas.drawPath(path, paint);
}
}
public void setAllRadius(float radius) {
isOval = false;
isAllRound = true;
this.radius = radius;
invalidate();
}
boolean isShowStroke = true;
public void showStroke(boolean showStroke) {
this.isShowStroke = showStroke;
invalidate();
}
public void setRadius(float ul_radius, float ur_radius, float ll_radius, float lr_radius) {
this.ul_radius = ul_radius;
this.ur_radius = ur_radius;
this.ll_radius = ll_radius;
this.lr_radius = lr_radius;
invalidate();
}
public void setStrokeColor(int strokeColor) {
this.strokeColor = strokeColor;
invalidate();
}
}
这个上面的PlayerView可以替换成其他ViewGroup，如果是View的话，直接重新onDraw就行了，没必要写
dispatchDraw，因为
绘制VIew本身的内容，通过调用View.onDraw(canvas)函数实现
绘制自己的孩子通过dispatchDraw（canvas）实现
View组件的绘制会调用draw(Canvas canvas)方法，draw过程中主要是先画Drawable背景，对 drawable调用setBounds()然后是draw(Canvas c)方法.有点注意的是背景drawable的实际大小会影响view组件的大小，drawable的实际大小通过getIntrinsicWidth()和getIntrinsicHeight()获取，当背景比较大时view组件大小等于背景drawable的大小
画完背景后，draw过程会调用onDraw(Canvas canvas)方法，然后就是dispatchDraw(Canvas canvas)方法, dispatchDraw()主要是分发给子组件进行绘制，我们通常定制组件的时候重写的是onDraw()方法。值得注意的是ViewGroup容器组件的绘制，当它没有背景时直接调用的是dispatchDraw()方法, 而绕过了draw()方法，当它有背景的时候就调用draw()方法，而draw()方法里包含了dispatchDraw()方法的调用。因此要在ViewGroup上绘制东西的时候往往重写的是dispatchDraw()方法而不是onDraw()方法，或者自定制一个Drawable，重写它的draw(Canvas c)和 getIntrinsicWidth(),