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POandroid get scroll position of listview populated with varied height
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copied!<p>In android, how do i get the scroll position of the listview?</p> <p>I know that I can retrieve the scroll position of a uniform populated listview with the following code:</p> <pre><code>int scrollY = -this.getChildAt(0).getTop() + this.getFirstVisiblePosition()* this.getChildAt(0).getHeight(); </code></pre> <p>the code assumes all heights of children(item) in the listview to be equal(<code>this.getChildAt(0).getHeight()</code>)</p> <p>Now, if i populate my listview with not equally sized items, how do i get the proper scroll position?</p> <p>My listview looks something like this: <img src="https://i.stack.imgur.com/ugKwN.png" alt="enter image description here"></p> <p>This is why I need the scroll position:</p> <pre><code>private Canvas drawIndicator(Canvas canvas) { int scrollY = getCurrentScrollPosition(); paint.setColor(Color.GRAY); paint.setAlpha(100); canvas.drawRect(getLeft(), indicatorPosition[0] - scrollY, getRight(), indicatorPosition[1] - scrollY, paint); //Log.d(VIEW_LOG_TAG, "drawIndicator:" + (indicatorPosition[1] - //scrollY)); paint.setColor(Color.parseColor("#47B3EA")); canvas.drawRect(getLeft(), indicatorPosition[1] - scrollY - (indicatorHeight / 2), getRight(), indicatorPosition[1] - scrollY + indicatorHeight, paint); return canvas; } </code></pre> <p>i need to draw a indicator that follows the scroll of the listview</p> <p>i would invoke it like </p> <pre><code>@Override protected void onDraw(Canvas canvas) { canvas.save(); canvas = drawIndicator(canvas); super.onDraw(canvas); canvas.restore(); } </code></pre>

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