Android自定义View图片按Path运动和旋转

本文实例为大家分享了Android自定义View图片按Path运动旋转的具体代码，供大家参考，具体内容如下

View：

/**
* author : stone
* email : aa86799@163.com
* time : 16/5/29 15 29
*/
public class EarthPathView extends View {

private Path mPath;
private Paint mPaint;
private Bitmap mBitmap;
private PathMeasure mPathMeasure;
private float[] mPoint;
private float[] mTan;
private float mDdegrees;

public EarthPathView(Context context) {
 this(context, null);
}

public EarthPathView(Context context, AttributeSet attrs) {
 this(context, attrs, 0);
}

public EarthPathView(Context context, AttributeSet attrs, int defStyleAttr) {
 super(context, attrs, defStyleAttr);

mPaint = new Paint();
 mPaint.setColor(Color.RED);
 mPaint.setStyle(Paint.Style.STROKE);
 mPaint.setStrokeWidth(10);

InputStream is = getResources().openRawResource(R.drawable.earth);
 mBitmap = BitmapFactory.decodeStream(is);

}

public void setPath(Path path) {
 mPath = path;
 mPathMeasure = new PathMeasure(path, false);
 mPoint = new float[2];
 mTan = new float[2];

}

@Override
protected void onDraw(Canvas canvas) {
 super.onDraw(canvas);
 if (mPath == null) {
  return;
 }

canvas.rotate(mDdegrees+=2, getWidth()/2, getHeight()/2);
 canvas.drawPath(mPath, mPaint);

float degress = (float) Math.toDegrees(Math.atan2(mTan[1], mTan[0]));
 Matrix matrix = new Matrix();
 matrix.postRotate(degress, mBitmap.getWidth() / 2, mBitmap.getHeight() / 2);
 matrix.postTranslate(mPoint[0] - mBitmap.getWidth() / 2, mPoint[1] - mBitmap.getHeight() / 2);
 canvas.drawBitmap(mBitmap, matrix, null);

}

@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public void startAnim() {
 ValueAnimator animator = ValueAnimator.ofFloat(0, mPathMeasure.getLength());
 animator.setDuration(2000);
 animator.setInterpolator(new LinearInterpolator()); //插值器
 animator.setRepeatCount(ValueAnimator.INFINITE);
 animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
  @Override
  public void onAnimationUpdate(ValueAnimator animation) {
   float distance = (float) animation.getAnimatedValue();
   mPathMeasure.getPosTan(distance, mPoint, mTan);
   invalidate();
  }
 });
 animator.start();
}
}

Activity

package com.stone.canvaspath;

import android.app.Activity;
import android.graphics.Path;
import android.os.Bundle;

import com.stone.canvaspath.earth.EarthPathView;

/**
* author : stone
* email : aa86799@163.com
* time : 16/5/29 15 27
*/
public class EarthActivity extends Activity {

private EarthPathView mPathView;
private Path mPath;

@Override
protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);

int w = getResources().getDisplayMetrics().widthPixels;
 int h = getResources().getDisplayMetrics().heightPixels;

mPathView = new EarthPathView(this);

setContentView(mPathView);

int min = Math.min(w, h);
 buildPath(w / 2 + 100, h / 2 + 100, min / 4);

mPathView.setPath(mPath);

mPathView.startAnim();
}

private void buildPath(float x, float y, float radius) {
 mPath = new Path();
 mPath.addCircle(x, y, radius, Path.Direction.CW);
}

}

来源：http://blog.csdn.net/jjwwmlp456/article/details/52046767