Develop Reference

How to Autoscroll to bottom on listview?

I have application with ListView. This ListView has a Progressbar.When I am clicking on this Progressbar, then it is showing a hided Layout(This layout contain textview with lyrics). So as I am clicking on the last Progressbar then it is showing the hided Layout, but I need to scroll manually. I want that scrolling must be automatically.
Please help me.

Try something like this:
private void scroll2bottom() {
yourListView.post(new Runnable() {
#Override
public void run() {
yourListView.setSelection(yourListAdapter.getCount() - 1);
}
});
}

You might find the smoothScrollByOffset() or smoothScrollBy() methods of ListView most useful. In particular smoothScrollBy() takes both a distance to scroll and a duration over which the scroll animation should take place. With this method you can control precisely how far to scroll the list.

in your layout of your listview just use the transcriptMode
a listview has builtin auto scroll
android:transcriptMode="normal" witll scroll when its at the bottom but not when you have scrolled away
and the setting alwaysScroll will always scroll to the bottom
and then you can set the android:stackFromBottom="true" to make it grow from the bottom

Try in this way:
lv.setTranscriptMode(ListView.TRANSCRIPT_MODE_ALWAYS_SCROLL);
lv.setStackFromBottom(true);

To scroll a listView programmatically you can use its smoothScrollByOffset(int offset) or smoothScrollToPosition(int position) methods, you can find here the documentation about the ListView widget and how to use those methods.

Set LinearLayout visible and call getBottom

In my app, I have a ScrollView with a LinearLayout whose visibility is set on GONE.
I need to make it visible and then have my ScrollView scroll to the bottom of the LinearLayout.
For this I'm using this code:
mLinearLayout.setVisibility(View.VISIBLE);
mScrollView.smoothScrollTo(0, mLinearLayout.getBottom());
This however, does not work. When the ScrollView is asked to scroll the LinearLayout still returns 0 on getBottom().
So when this is called for the first time, the LinearLayout is visible, but the scrollview has not scrolled.
When it is called for a second time, it does scroll down to the right position.
How can I fix this?

You need to put your smmothScrollTo method inside a new thread like this:
mScrollView.post(new Runnable() {
public void run() {
mScrollView.smoothScrollTo(0,mLinearLayout.getBottom());
}
});

How to change a header TextView Text when during scrolling of Horizontal scrollView?

I have a horizontal scroll view, I also have a relativelayout as it's child. I am adding child views of this relativelayout dynamically. I have a header text which should be update when I scroll according to respective child views. How can I do this because I am able to get the current focused item in horizontal scroll. Please give me some suggestion or examples which can be helpful for me, thanks..

You should specify an OnTouchListener for your HorizontalScrollView and in it's onTouch() method detect the type of MotionEvent and change your TextView's color to the appropriate

If you are creating this childs dinamically you can set a tag to them with the content you want to show in the header TextView.
//Creating RelativeLayout childs
TextView newChild = new TextView(this).
newChild.setTag(textToShowWhenThisItemIsFocused);
Then if you know which item is focused you just have to get the tag.
// "selected" is the focused view
header.setText((String) selected.getTag());
When to use the second code depends on your implementation. Since you didn't provide any code it's hard to know how to monitor the scroll, but i.e. you could control Touch Events and update the header when the user is moving his finger over the screen (you should also take into account the inertia after the user stops tapping).
EDIT: How to get the focused View
First of all, I barely have experience doing things like this, so I'm not sure if this is going to work or if there are better ways to do it. I'll just tell you the way I would approach this problem.
To be able to know the focused View you need to know the coordinates where this View should be. Since it's an horizontal ScrollView we will need the X coordinate. Since we want the View in the middle of the ScrollView I would do it like this:
private int centerSV;
private ScrollView mScrollView;
...
centerSV = mScrollView.getWidth()/2;
Now we have the center of the ScrollView. Now we need to know which child is in this position:
private int getFocusedChildId(){
for(int i=0; i<mChilds.length; i++){
int childLeftCoord = mChilds[i].getLeft() - mScrollView.getScrollX();
if(childLeftCoord <= centerSV && centerSV <= childLeftCoord + mChilds[i].getWidth())
return mChilds[i].getId();
}
// No view found in the center, maybe ScrollView wasn't full. Return the first one
return mChilds[0].getId();
}
Again, I'm not sure if this is going to work, it's just an idea of how to approach your issue. Also, you should take this into account:
getWidth() and getHeight() of View returns 0

Android: how to force ScrollView layout, and then scroll to a point?

I have a ScrollView which I'm adding a number of custom Views to. After adding the custom Views, I would like to be able to Scroll to a particular one. But, immediately after adding the custom views, the ScrollView hasn't been resized, so I can not scroll. Any idea how I can force this resize?
for(int i = 0, i < numberOfViews, i++)
{
scrollView.addView(new MyView(...));
}
//tried this, doesn't seem to be helpful
scrollView.requestLayout();
//at this point scrollView dimensions are 0,0,0,0
scrollView.scrollTo(5, 200);

I'm not completely sure what you're trying to do, but I wanted to scroll all the way down, and couldn't just do that: I had to do it like this:
((ScrollView) findViewById(R.id.yourId)).post(new Runnable() {
public void run() {
((ScrollView) findViewById(R.id.yourId)).fullScroll(View.FOCUS_DOWN);
}
});
It will update later, so your view is made :)

An elegant solution is to plan the scroll and do it on the next onLayout(). Example code here:
https://stackoverflow.com/a/10209457/1310343

Scrolling issues with a ListView inside a ScrollView

Here's the scenario conceptually (excluding linearlayouts)
ScrollView
Button
Checkboxes
Spinner
ListView (full-size, non-scrolling)
AdMob advert
i.e. a scrolling pane, which has a filtering UI at the top, followed by results, but the advert must always remain visible, and when scrolling down the filter UI must scroll away, leaving maximum space for results.
I'm aware there are issues with a ListView inside a ScrollView, though for me it is working well in many ways (I'm fixing the length of the ListView to stop it collapsing). So the screen scrolls nicely, the ad stays put at the bottom, and it looks good.
But the problem I'm seeing is, inexplicably, when the activity opens, the ScrollView is scrolled down a bit, so the ListView is at the top of the screen. I assume this is a default behaviour, so I set about trying to force the scroll position of the ScrollView to the top, but I've tried various methods, and see no effect:
scrollview.scrollTo(0, 1000/-1000);
scrollview.smoothScrollBy(0, 1000/-1000);
scrollview.fullScroll(View.FOCUS_UP);
Is there any way to force the ScrollView to start with the scroll position at the top?
If not, how can I have an ad that doesn't scroll off the bottom, but a filter UI that always scrolls off the top? Using ListView seems overkill as I don't need scrolling but it does provide many benefits so would be nice to avoid starting from scratch and rendering everything myself.

Use the following method and enjoy!
private void setListViewScrollable(final ListView list) {
list.setOnTouchListener(new OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
listViewTouchAction = event.getAction();
if (listViewTouchAction == MotionEvent.ACTION_MOVE)
{
list.scrollBy(0, 1);
}
return false;
}
});
list.setOnScrollListener(new OnScrollListener() {
#Override
public void onScrollStateChanged(AbsListView view,
int scrollState) {
}
#Override
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
if (listViewTouchAction == MotionEvent.ACTION_MOVE)
{
list.scrollBy(0, -1);
}
}
});
}
listViewTouchAction is a global integer value.
If you can replace the line
list.scrollBy(0, 1);
with something else please share it with us.

Why are you using a listview if you're not scrolling? Why can't you just use a linearlayout or something more fit to this situation? You mention a filter, you could very easily roll your own filter especially since apparently you just have a few items in your listview.

Use something other that a ListView, you can dinamically generate linearLayouts to show the data you want. You should never use a listview inside a scrollView, it doesnt work for a simple reason, when you scroll, what should scroll, the listview or the scroll view. A couple of people from google have stated not to do this.

I've experienced the issue of a ScrollView starting off scrolled down slightly, the solution was to post a runnable which called the animateTo(0,0) method to get the list to scroll to the top. I found this only worked using anitmatTo(0,0) scrollTo(0,0) didn't seem to work.
Something along the lines of:
mListView.post(new Runnable(){ public void run() { mListView.animateScrollTo(0,0) });
Now as everyone has already stated you shouldn't do the whole ListView inside a ScrollView, but this may be a fix for the problem you had.

I have:
ScrollView
TextView
Button
TextView
ListView
and this work good for me:
scrollView.smoothScrollBy(0, 0);
without this view start from position of listview, after that it start from top

The solution for this issue is to make a request focus to an object in the top of the ScrollView. For example you can use a table layout wrapping the button and request focus to the table layout (If you focus the button it will change its color).
// onCreate method
TableLayout tablelayout = (TableLayout) findViewById(R.id.tablelayout);
tablelayout.setFocusableInTouchMode(true);
tablelayout.requestFocus();