X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=tests%2Funderlay-callback.html;h=d077e2f7e801f7f170d9238da1369ff8108fb9a2;hb=606568fef36a321148399da4c58a05e2753ac2f9;hp=71857eb9acaac662d5f75d6b0587aa38d8e826fc;hpb=2fc82862911aedb6cd30287a040b827c75405512;p=dygraphs.git
diff --git a/tests/underlay-callback.html b/tests/underlay-callback.html
index 71857eb..d077e2f 100644
--- a/tests/underlay-callback.html
+++ b/tests/underlay-callback.html
@@ -1,3 +1,4 @@
+
Custom underlay callback
@@ -27,16 +28,35 @@
errorBars: true,
underlayCallback: function(canvas, area, g) {
- var splitHeight = g.toDomCoords(null, 2.25)[1];
+ // Selecting a date in the middle of the graph.
+ var splitDate = new Date("2006-11-19").getTime();
+ var coords = g.toDomCoords(splitDate, 2.25);
- // fillRect(x, y, width, height)
- // Bottom section: y = (-Infinity, 2.25)
- canvas.fillStyle = 'pink';
- canvas.fillRect(area.x, splitHeight, area.w, area.h - splitHeight);
+ // splitX and splitY are the coordinates on the canvas for (2006-11-19, 2.25).
+ var splitX = coords[0];
+ var splitY = coords[1];
+
+ // The drawing area doesn't start at (0, 0), it starts at (area.x, area.y).
+ // That's why we subtract them from splitX and splitY. This gives us the
+ // actual distance from the upper-left hand corder of the graph itself.
+ var leftSideWidth = splitX - area.x;
+ var rightSideWidth = area.w - leftSideWidth;
+ var topHeight = splitY - area.y;
+ var bottomHeight = area.h - topHeight;
+ // fillRect(x, y, width, height)
// Top section: y = (2.25, +Infinity)
+ // left: (x < 2006-11-19)
canvas.fillStyle = 'lightblue';
- canvas.fillRect(area.x, area.y, area.w, splitHeight - area.y);
+ canvas.fillRect(area.x, area.y, leftSideWidth, topHeight);
+
+ // right: (x > 2006-11-19)
+ canvas.fillStyle = 'orange';
+ canvas.fillRect(splitX, area.y, rightSideWidth, topHeight);
+
+ // Bottom section: y = (-Infinity, 2.25)
+ canvas.fillStyle = 'pink';
+ canvas.fillRect(area.x, splitY, area.w, bottomHeight);
}
}
);