如何让一个圆围绕轴心转一定的角度

[hzgmm]

让一个圆形图片围绕圆心（轴心）旋转一定的角度，要用到什么哪个函数？每点击一次上下键就旋转一定角度！

谢谢

[j_f0001]

两种方法
1.canvas.rotate(角度);
2.使用Matrix进行矩阵变化.

[编号27149]

/**
* 图片旋转指定角度
* @param resizedBitmap 位图
* @param image View
* @param scaleAngle 旋转角度值
* @return
*/
private ImageView pointerRotation(Bitmap resizedBitmap,ImageView image,int scaleAngle)
{

//scaleAngle=360-45+scaleAngle;

int ScaleTimes=1;

int oldWidth = resizedBitmap.getWidth();
int oldHeight = resizedBitmap.getHeight() ;

/* ScaleTimes=1，维持1:1的宽高比例*/
int newWidth = resizedBitmap.getWidth()*ScaleTimes ;
int newHeight = resizedBitmap.getHeight()*ScaleTimes ;

float scaleWidth = (float) newWidth / resizedBitmap.getWidth();
float scaleHeight = (float) newHeight / resizedBitmap.getHeight();

Matrix matrix = new Matrix();
/* 使用Matrix.postScale设定维度 */
matrix.postScale(scaleWidth, scaleHeight);
/* 使用Matrix.postRotate方法旋转Bitmap*/
//matrix.postRotate(5*ScaleAngle);
matrix.setRotate(scaleAngle);
/* 建立新的Bitmap对象 */
resizedBitmap =Bitmap.createBitmap(resizedBitmap, 0, 0, oldWidth, oldHeight, matrix, true);
/**/
BitmapDrawable myNewBitmapDrawable =new BitmapDrawable(resizedBitmap);
image.setImageDrawable(myNewBitmapDrawable);


//imageView1.image.setBackgroundResource(R.drawable.mainbuttoneffect);

int h=resizedBitmap.getHeight();
int w=resizedBitmap.getWidth();
image.setLayoutParams ( new AbsoluteLayout.LayoutParams (w,h,(int) (screenW-w)/2,(int)(screenH-2*h)/2 ));

SourceLocationX=(screenW-w)/2;
SourceLocationY=(screenH-2*h)/2;


return image;
}

zh


这是我从程序中截取的函数，试着改成你想要的，应该可以满足你的