安卓：图片的自由裁剪

Question

我想在图片上自由裁剪... 图片可以来自相册，也可以来自相机...是否有相关的解决方案？

- Krunal Desai

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你以前使用过 SurfaceView 吗？ - kabuto178

@kabuto178 还没有... - Krunal Desai

Answer 1

• 从图库或相机加载图像到视图（使用Canvas绘制图像）

   public class SomeView extends View implements OnTouchListener {
      private Paint paint;
      public static List<Point> points;
      int DIST = 2;
      boolean flgPathDraw = true;
  Point mfirstpoint = null;
      boolean bfirstpoint = false;
  Point mlastpoint = null;
  Bitmap bitmap = BitmapFactory.decodeResource(getResources(),
              R.drawable.gallery_12);
      Context mContext;
   public SomeView(Context c) {
          super(c);
  mContext = c;
          setFocusable(true);
          setFocusableInTouchMode(true);
   paint = new Paint(Paint.ANTI_ALIAS_FLAG);
          paint.setStyle(Paint.Style.STROKE);
          paint.setPathEffect(new DashPathEffect(new float[] { 10, 20 }, 0));
          paint.setStrokeWidth(5);
          paint.setColor(Color.WHITE);
  this.setOnTouchListener(this);
          points = new ArrayList<Point>();
  bfirstpoint = false;
      }
   public SomeView(Context context, AttributeSet attrs) {
          super(context, attrs);
          mContext = context;
          setFocusable(true);
          setFocusableInTouchMode(true);
   paint = new Paint(Paint.ANTI_ALIAS_FLAG);
          paint.setStyle(Paint.Style.STROKE);
          paint.setStrokeWidth(2);
          paint.setColor(Color.WHITE);
  this.setOnTouchListener(this);
          points = new ArrayList<Point>();
          bfirstpoint = false;
  }
   public void onDraw(Canvas canvas) {
          canvas.drawBitmap(bitmap, 0, 0, null);
  Path path = new Path();
          boolean first = true;
  for (int i = 0; i < points.size(); i += 2) {
              Point point = points.get(i);
              if (first) {
                  first = false;
                  path.moveTo(point.x, point.y);
              } else if (i < points.size() - 1) {
                  Point next = points.get(i + 1);
                  path.quadTo(point.x, point.y, next.x, next.y);
              } else {
                  mlastpoint = points.get(i);
                  path.lineTo(point.x, point.y);
              }
          }
          canvas.drawPath(path, paint);
      }
   public boolean onTouch(View view, MotionEvent event) {
          // if(event.getAction() != MotionEvent.ACTION_DOWN)
          // return super.onTouchEvent(event);
  Point point = new Point();
          point.x = (int) event.getX();
          point.y = (int) event.getY();
  if (flgPathDraw) {
  if (bfirstpoint) {
  if (comparepoint(mfirstpoint, point)) {
                      // points.add(point);
                      points.add(mfirstpoint);
                          flgPathDraw = false;
                                          showcropdialog();
                  } else {
                      points.add(point);
                  }
              } else {
                  points.add(point);
              }
  if (!(bfirstpoint)) {
  mfirstpoint = point;
                  bfirstpoint = true;
              }
          }
  invalidate();
          Log.e("Hi  ==>", "Size: " + point.x + " " + point.y);
  if (event.getAction() == MotionEvent.ACTION_UP) {
              Log.d("Action up*******~~~~~~~>>>>", "called");
              mlastpoint = point;
              if (flgPathDraw) {
                  if (points.size() > 12) {
                      if (!comparepoint(mfirstpoint, mlastpoint)) {
                          flgPathDraw = false;
                          points.add(mfirstpoint);
                          showcropdialog();
                      }
                  }
              }
          }
  return true;
      }
   private boolean comparepoint(Point first, Point current) {
          int left_range_x = (int) (current.x - 3);
          int left_range_y = (int) (current.y - 3);
  int right_range_x = (int) (current.x + 3);
          int right_range_y = (int) (current.y + 3);
  if ((left_range_x < first.x && first.x < right_range_x)
                  && (left_range_y < first.y && first.y < right_range_y)) {
              if (points.size() < 10) {
                  return false;
              } else {
                  return true;
              }
          } else {
              return false;
          }
  }
   public void fillinPartofPath() {
          Point point = new Point();
          point.x = points.get(0).x;
          point.y = points.get(0

- user2106230

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我使用了这个方法，但是无法从裁剪区域获取位图。在保存时，它包含了背景和裁剪后的图像。 - Deepak Jangir

@noviceAndroid 你能告诉我如何从裁剪区域获取位图吗？以及如何在获取位图时避免图像周围的额外区域。 - Mustanser Iqbal

如果您想删除位图的额外部分，只需删除传输部分，这样您就可以获得原始裁剪图像。 - Kishan patel

@noviceAndroid 如何在onDraw中完成此操作，而不是在CropActivity中创建另一个位图 - http://stackoverflow.com/questions/36943983/android-crop-bitmap-canvas?noredirect=1#comment61446920_36943983。 - zek54

我想实现手动、方形、圆形和任意形状裁剪功能。那么你有完整库的参考资料吗？ - Anand Savjani