帮我实现贝塞尔曲线效果
时间: 2023-10-21 12:03:43 浏览: 110
好的,下面是一个简单的贝塞尔曲线效果的实现步骤:
1. 在 XML 文件中创建一个自定义 View。例如:
```
<com.example.beziercurve.BezierCurveView
android:id="@+id/bezierCurveView"
android:layout_width="match_parent"
android:layout_height="match_parent" />
```
2. 创建一个 BezierCurveView 类,继承自 View,并在其中实现 onDraw() 方法。例如:
```
public class BezierCurveView extends View {
private Paint mPaint;
private Path mPath;
public BezierCurveView(Context context) {
super(context);
init();
}
public BezierCurveView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public BezierCurveView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() {
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
mPaint.setColor(Color.RED);
mPaint.setStrokeWidth(5);
mPaint.setStyle(Paint.Style.STROKE);
mPath = new Path();
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
int width = getWidth();
int height = getHeight();
// 定义 4 个点
PointF start = new PointF(width / 4, height / 2);
PointF end = new PointF(width * 3 / 4, height / 2);
PointF control1 = new PointF(width / 4, height / 4);
PointF control2 = new PointF(width * 3 / 4, height * 3 / 4);
// 绘制贝塞尔曲线
mPath.reset();
mPath.moveTo(start.x, start.y);
mPath.cubicTo(control1.x, control1.y, control2.x, control2.y, end.x, end.y);
canvas.drawPath(mPath, mPaint);
}
}
```
3. 在 Activity 中,获取 BezierCurveView 控件,并将其显示出来。例如:
```
BezierCurveView bezierCurveView = (BezierCurveView) findViewById(R.id.bezierCurveView);
setContentView(bezierCurveView);
```
这样,一个简单的贝塞尔曲线效果就完成了。您可以根据需要调整点的位置和曲线的形状来创建不同的曲线效果。
阅读全文