Marker Animation?

[gcgrant]

I'm attempting to animate the Marker coming into view. I have extended MarkerView and not been able to find any way to do this. I think something in the library is overriding this ability.

Is there something I am missing or is there a way to animate the Marker into being visible?

Trying to use the auto android transitions using android:animateLayoutChanges="true" does not work if put on the Graph or the parent of the Graph or the tooltip layout.

I also attempted using view animators in the custom marker class, but no matter what I did the marker always pops in with no animation. I am unclear if I am doing something wrong or if there is a limitation in the library. The only other reference to this I could find is this which was closed without response:

#2197

Any insight would be appreciated, apologies if this is just me being dumb 👍

[gcgrant]

This Kotlin code exhibits the problem:

override fun refreshContent(e: Entry?, highlight: Highlight?) {
        val viewModel = viewModels.getOrNull(e?.x?.toInt() ?: return)
        viewModel?.let { vm ->
            // do things
        }

        animator.removeAllUpdateListeners()
        animator.addUpdateListener {
            super.refreshContent(e, highlight)
        }

        animator.start()
    }

    override fun onDraw(canvas: Canvas?) {
        val scaleX = animator.getAnimatedValue("scaleX") as Float
        val scaleY = animator.getAnimatedValue("scaleY") as Float
        Log.e("TEST", "x: $scaleX, y: $scaleY")
        transformMatrix.reset()
        transformMatrix.postScale(scaleX, scaleY)
        canvas?.concat(transformMatrix)
        super.onDraw(canvas)
    }

No matter what I try, whether I call super.refreshContent, super.draw(canvas, posX, posY), invalidate(), postInvalidate(), requestLayout(), etc, nothing will cause onDraw to be called more than once (even though the animator is running properly). Is something in the library preventing invalidation of the tooltip? That would explain why I can't seem to animate this.

This is in a class that extends MarkerView, with setWillNotDraw(false) already set (so invalidating should cause an onDraw call).

[gcgrant]

Some more weird behaviour:

    override fun draw(canvas: Canvas?, posX: Float, posY: Float) {
        val anim = ObjectAnimator.ofFloat(0.1f, 1f)
        anim.duration = 2500
        anim.addUpdateListener {
            paint.alpha = (it.animatedValue as Float * 255).toInt()
            canvas?.drawPaint(paint)
            super.draw(canvas, posX, posY)
        }
        anim.start()
    }

Attempting to do a simple alpha animation exhibits the same issue -- it appears that as soon as draw(canvas) is called, the view refuses to be layed out again.

Oddly, when manipulating the canvas' alpha, it seems to be affecting the graph itself, and not the popup? Modifying the marker view's alpha seems to do absolutely nothing.

[gcgrant]

The modification of the graph's alpha is likely due to the fact that both views seem to share a canvas:

https://github.com/PhilJay/MPAndroidChart/blob/master/MPChartLib/src/main/java/com/github/mikephil/charting/charts/BarLineChartBase.java#L28

[almic]

@gcgrant Looking at the source in Chart.java, I can see that markers are drawn on the same canvas as everything else in the chart, and will animate only to stay positioned with the data. To get what you want would probably require a total rewrite of the marker classes. Markers are just told when and where to draw, and use the RelativeLayout view to do so. I don't know enough about how the Marker view works to say anything for sure, but I will look into it.

[chengsl123]

这个问题有解决了吗 ？告诉我解决方式，谢谢