1 files changed, 73 insertions, 0 deletions
diff --git a/android/source/src/java/org/libreoffice/canvas/SelectionHandle.java b/android/source/src/java/org/libreoffice/canvas/SelectionHandle.java
new file mode 100644
index 000000000..ddd16fe5e
--- /dev/null
+++ b/android/source/src/java/org/libreoffice/canvas/SelectionHandle.java
@@ -0,0 +1,73 @@
+package org.libreoffice.canvas;
+
+import android.graphics.Bitmap;
+import android.graphics.PointF;
+
+import org.libreoffice.LOKitShell;
+import org.libreoffice.LibreOfficeMainActivity;
+import org.mozilla.gecko.gfx.ImmutableViewportMetrics;
+
+/**
+ * Selection handle is a common class for "start", "middle" and "end" types
+ * of selection handles.
+ */
+public abstract class SelectionHandle extends BitmapHandle {
+    private static final long MINIMUM_HANDLE_UPDATE_TIME = 50 * 1000000;
+
+    private final PointF mDragStartPoint = new PointF();
+    private final PointF mDragDocumentPosition = new PointF();
+    private long mLastTime = 0;
+
+    private LibreOfficeMainActivity mContext;
+
+    public SelectionHandle(LibreOfficeMainActivity context, Bitmap bitmap) {
+        super(bitmap);
+        mContext = context;
+    }
+
+    /**
+     * Start of a touch and drag action on the handle.
+     */
+    public void dragStart(PointF point) {
+        mDragStartPoint.x = point.x;
+        mDragStartPoint.y = point.y;
+        mDragDocumentPosition.x = mDocumentPosition.left;
+        mDragDocumentPosition.y = mDocumentPosition.top;
+    }
+
+    /**
+     * End of a touch and drag action on the handle.
+     */
+    public void dragEnd(PointF point) {
+    }
+
+    /**
+     * Handle has been dragged.
+     */
+    public void dragging(PointF point) {
+        long currentTime = System.nanoTime();
+        if (currentTime - mLastTime > MINIMUM_HANDLE_UPDATE_TIME) {
+            mLastTime = currentTime;
+            signalHandleMove(point.x, point.y);
+        }
+    }
+
+    /**
+     * Signal to move the handle to a new position to LO.
+     */
+    private void signalHandleMove(float newX, float newY) {
+        ImmutableViewportMetrics viewportMetrics = mContext.getLayerClient().getViewportMetrics();
+        float zoom = viewportMetrics.zoomFactor;
+
+        float deltaX = (newX - mDragStartPoint.x) / zoom;
+        float deltaY = (newY - mDragStartPoint.y) / zoom;
+
+        PointF documentPoint = new PointF(mDragDocumentPosition.x + deltaX, mDragDocumentPosition.y + deltaY);
+
+        LOKitShell.sendChangeHandlePositionEvent(getHandleType(), documentPoint);
+    }
+
+    public abstract HandleType getHandleType();
+
+    public enum HandleType { START, MIDDLE, END }
+}