图片阴影效果和影子效果

2019-04-15 13:13发布

import android.app.Activity; import android.os.Bundle; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.PorterDuff; import android.graphics.PorterDuff.Mode; import android.graphics.PorterDuffXfermode; import android.graphics.Rect; import android.graphics.RectF; import android.graphics.drawable.Drawable; import android.view.View; public class ShaderEffect extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(new ImageEffect(this)); } class ImageEffect extends View{ Paint paint; public ImageEffect (Context context){ super(context); paint = new Paint();//初始化画笔,为后面阴影效果使用。 paint.setAntiAlias(true);//去除锯齿。 paint.setShadowLayer(5f, 5.0f, 5.0f, Color.BLACK);//设置阴影层,这是关键。 paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN)); } @Override public void onDraw(Canvas canvas){ super.onDraw(canvas); int posX = 20; int posY = 50; int PicWidth,PicHegiht; Drawable drawable = getResources().getDrawable(R.drawable.button); Drawable dbe = getResources().getDrawable(R.drawable.button).mutate();//如果不调用mutate方法,则原图也会被改变, //因为调用的资源是同一个,所有对象是共享状态的。 Drawable drawTest = getResources().getDrawable(R.drawable.button); Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.button); PicWidth = drawable.getIntrinsicWidth(); PicHegiht = drawable.getIntrinsicHeight(); drawTest.setBounds(posX, (2 * posY) + PicHegiht, posX + PicWidth, (2 * posY) + 2 * PicHegiht ); drawable.setBounds(posX,posY,posX+PicWidth,posY+PicHegiht); dbe.setBounds(0, 0, PicWidth, PicHegiht); canvas.drawColor(Color.WHITE);//设置画布颜 {MOD} canvas.save(Canvas.MATRIX_SAVE_FLAG); dbe.setColorFilter(0x7f000000,PorterDuff.Mode.SRC_IN); canvas.translate(posX + (int)(0.9 * PicWidth/2), posY + PicHegiht/2);//图像平移为了刚好在原图后形成影子效果。 canvas.skew(-0.9F, 0.0F);//图像倾斜效果。 canvas.scale(1.0f, 0.5f);//图像(其实是画布)缩放,Y方向缩小为1/2。 dbe.draw(canvas);//此处为画原图像影子效果图,比原图先画,则会在下层。 drawable.clearColorFilter(); canvas.restore(); canvas.save(Canvas.MATRIX_SAVE_FLAG); drawable.draw(canvas);//此处为画原图像,由于canvas有层次效果,因此会盖在影子之上。 canvas.restore(); //默认无效果原图 canvas.save(Canvas.MATRIX_SAVE_FLAG); drawTest.draw(canvas); canvas.restore(); //图片阴影效果 canvas.save(Canvas.MATRIX_SAVE_FLAG); //Rect rect = new Rect(2*posX + PicWidth, 2*posY + PicHegiht, 2*posX + 2*PicWidth, 2*posY + 2*PicHegiht);//此为理论上的阴影图坐标 Rect rect = new Rect(2*posX + PicWidth + 3, 2*posY + PicHegiht + 3, 2*posX + 2*PicWidth - 2, 2*posY + 2*PicHegiht - 2); //由于图片的实际尺寸比显示出来的图像要大一些,因此需要适当更改下大小,以达到较好的效果 RectF rectF = new RectF(rect); canvas.drawRoundRect(rectF, 10f, 10f, paint);//在原有矩形基础上,画成圆角矩形,同时带有阴影层。 canvas.drawBitmap(bmp, 2*posX + PicWidth, 2*posY + PicHegiht, null);//画上原图。 canvas.restore(); } } }