1 files changed, 141 insertions, 0 deletions
diff --git a/sample/src/main/java/com/davemorrissey/labs/subscaleview/test/extension/views/FreehandView.java b/sample/src/main/java/com/davemorrissey/labs/subscaleview/test/extension/views/FreehandView.java
new file mode 100644
index 0000000..f4f1403
--- /dev/null
+++ b/sample/src/main/java/com/davemorrissey/labs/subscaleview/test/extension/views/FreehandView.java
@@ -0,0 +1,141 @@
+package com.davemorrissey.labs.subscaleview.test.extension.views;
+
+import android.content.Context;
+import android.graphics.*;
+import android.graphics.Paint.Cap;
+import android.graphics.Paint.Style;
+import android.support.annotation.NonNull;
+import android.util.AttributeSet;
+import android.view.MotionEvent;
+import android.view.View;
+import android.view.View.OnTouchListener;
+import com.davemorrissey.labs.subscaleview.SubsamplingScaleImageView;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class FreehandView extends SubsamplingScaleImageView implements OnTouchListener {
+
+    private final Paint paint = new Paint();
+    private final Path vPath = new Path();
+    private final PointF vPoint = new PointF();
+    private PointF vPrev = new PointF();
+    private PointF vPrevious;
+    private PointF vStart;
+    private boolean drawing = false;
+
+    private int strokeWidth;
+
+    private List<PointF> sPoints;
+
+    public FreehandView(Context context, AttributeSet attr) {
+        super(context, attr);
+        initialise();
+    }
+
+    public FreehandView(Context context) {
+        this(context, null);
+    }
+
+    private void initialise() {
+        setOnTouchListener(this);
+        float density = getResources().getDisplayMetrics().densityDpi;
+        strokeWidth = (int)(density/60f);
+    }
+
+    @Override
+    public boolean onTouch(View view, MotionEvent motionEvent) {
+        return false;
+    }
+
+    @Override
+    public boolean onTouchEvent(@NonNull MotionEvent event) {
+        if (sPoints != null && !drawing) {
+            return super.onTouchEvent(event);
+        }
+        boolean consumed = false;
+        int touchCount = event.getPointerCount();
+        switch (event.getActionMasked()) {
+            case MotionEvent.ACTION_DOWN:
+                if (event.getActionIndex() == 0) {
+                    vStart = new PointF(event.getX(), event.getY());
+                    vPrevious = new PointF(event.getX(), event.getY());
+                } else {
+                    vStart = null;
+                    vPrevious = null;
+                }
+                break;
+            case MotionEvent.ACTION_MOVE:
+                PointF sCurrentF = viewToSourceCoord(event.getX(), event.getY());
+                PointF sCurrent = new PointF(sCurrentF.x, sCurrentF.y);
+                PointF sStart = vStart == null ? null : new PointF(viewToSourceCoord(vStart).x, viewToSourceCoord(vStart).y);
+
+                if (touchCount == 1 && vStart != null) {
+                    float vDX = Math.abs(event.getX() - vPrevious.x);
+                    float vDY = Math.abs(event.getY() - vPrevious.y);
+                    if (vDX >= strokeWidth * 5 || vDY >= strokeWidth * 5) {
+                        if (sPoints == null) {
+                            sPoints = new ArrayList<>();
+                            sPoints.add(sStart);
+                        }
+                        sPoints.add(sCurrent);
+                        vPrevious.x = event.getX();
+                        vPrevious.y = event.getY();
+                        drawing = true;
+                    }
+                    consumed = true;
+                    invalidate();
+                } else if (touchCount == 1) {
+                    // Consume all one touch drags to prevent odd panning effects handled by the superclass.
+                    consumed = true;
+                }
+                break;
+            case MotionEvent.ACTION_UP:
+            case MotionEvent.ACTION_POINTER_UP:
+                invalidate();
+                drawing = false;
+                vPrevious = null;
+                vStart = null;
+        }
+        // Use parent to handle pinch and two-finger pan.
+        return consumed || super.onTouchEvent(event);
+    }
+
+    @Override
+    protected void onDraw(Canvas canvas) {
+        super.onDraw(canvas);
+
+        // Don't draw anything before image is ready.
+        if (!isReady()) {
+            return;
+        }
+
+        paint.setAntiAlias(true);
+
+        if (sPoints != null && sPoints.size() >= 2) {
+            vPath.reset();
+            sourceToViewCoord(sPoints.get(0).x, sPoints.get(0).y, vPrev);
+            vPath.moveTo(vPrev.x, vPrev.y);
+            for (int i = 1; i < sPoints.size(); i++) {
+                sourceToViewCoord(sPoints.get(i).x, sPoints.get(i).y, vPoint);
+                vPath.quadTo(vPrev.x, vPrev.y, (vPoint.x + vPrev.x) / 2, (vPoint.y + vPrev.y) / 2);
+                vPrev = vPoint;
+            }
+            paint.setStyle(Style.STROKE);
+            paint.setStrokeCap(Cap.ROUND);
+            paint.setStrokeWidth(strokeWidth * 2);
+            paint.setColor(Color.BLACK);
+            canvas.drawPath(vPath, paint);
+            paint.setStrokeWidth(strokeWidth);
+            paint.setColor(Color.argb(255, 51, 181, 229));
+            canvas.drawPath(vPath, paint);
+        }
+
+    }
+
+    public void reset() {
+        this.sPoints = null;
+        invalidate();
+    }
+
+}