Develop Reference

How to detect motions on a scrollable textview

I have a textview which only shows 3 lines and then you have to scroll to the other ones.
I set the textview in my xml file as scrollable and activated its scrolling method with textview.setMovementMethod(new ScrollingMovementMethod()).
The scrolling works perfectly fine.
The problem I face is, that I need to know when the user has scrolled to the bottom of the textview in the case that the textview has more than 3 lins. Is there a way to check when the user has scrolled to bottom of the textview?
I played a little bit around with the OnTouchListener, OnDragListener and OnHoverListener but none of them really worked.
If you need more details, just let me know.
Thanks for your help!

You can try this :
scrollView.getViewTreeObserver()
.addOnScrollChangedListener(new ViewTreeObserver.OnScrollChangedListener() {
#Override
public void onScrollChanged() {
if (scrollView.getChildAt(0).getBottom()
<= (scrollView.getHeight() + scrollView.getScrollY())) {
//scroll view is at bottom
} else {
//scroll view is not at bottom
}
}
});
Best

How to divide large string data in multiple pages or activity or fragments or flips

I am trying to do a task but after wasting so much time still i didn't get any solution.
Problem: I am working on a news application, with flip effect. application shows a news content on first page, when user swipes bottom to top on screen an new flip opens and remaining news text content will be shown on next all flips.
The problem is, i set the initial text news on first screen on a text view, but when user swipe for more news, i am unable to detect how much text data i have shown on the first text, and how much i have remaining text data to set on next flip.
I searched many times that is there any function to get visible text on text view, but there is no solution for that, some logics are there but they are not working for me.
Thanks.

public int getEllipsisStart (int line)
Return the offset of the first character to be ellipsized away,
relative to the start of the line. (So 0 if the beginning of the line
is ellipsized, not getLineStart().)
This means that you can find out if your text has been ellipsized or not like this:
int ellipsisStart = mTextView.getLayout().getEllipsisStart() > 0;
if (ellipsisStart > 0) {
// your text has been ellipsized
// your text for the next page should be
// String nextPageText = myString.subString(ellipsisStart);
} else {
// your text fits on the first page
}
But remember that getLayout() will return null before the layout has been set, so you can use a ViewTreeObserver to find out if the layout has been laid out.
ViewTreeObserver observer = mTextview.getViewTreeObserver();
observer.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
Layout layout = textview.getLayout();
if ( layout != null) {
// get your ellipsisStart
}
}
});

Can I partially hide a layout?

As I've a master in MS Paint, I will just upload a picture selfdescripting what I'm trying to achieve.
I've searched, but I'm not really sure what do I've to search. I've found something called Animations. I managed to rotate, fade, etc an element from a View (with this great tutorial http://www.vogella.com/articles/AndroidAnimation/article.html)
But this is a bit limited for what I'm trying to achieve, and now, I'm stuck, because I don't know how is this really called in android development. Tried words like "scrollup layouts" but I didn't get any better results.
Can you give me some tips?
Thank you.
You can see a live example, with this app: https://play.google.com/store/apps/details?id=alexcrusher.just6weeks
Sincerely,
Sergi

Use something like this as your layout (Use Linear, Relative or other layout if you wish):
<LinearLayout
android:id="#+id/lty_parent">
<LinearLayout
android:id="#+id/lyt_first" />
<LinearLayout
android:id="#+id/lyt_second"/>
</LinearLayout>
And then in an onClick method on whatever you want to use to control it, set the Visibility between Visible and Gone.
public void buttonClickListener(){
((Button) findViewById(R.id.your_button))
.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
if (lyt_second.getVisibility() == View.GONE) {
lyt_second.setVisibility(View.VISIBILE);
}
else {
lyt_second.setVisibility(View.GONE);
}
});
Which is fine if you just want a simple appear/disappear with nothing fancy. Things get a little bit more complicated if you want to animate it, as you need to play around with negative margins in order to make it appear to grow and shrink, like so:
We use the same onClick method that we did before, but this time when we click it starts up a custom SlideAnimation for the hidden/visible view.
#Override
public void onClick(View v) {
SlideAnimation slideAnim = new SlideAnimation(lyt_second, time);
lyt_second.startAnimation(slideAnim);
}
The implementation of the SlideAnimation is based on a general Animation class, which we extend and then Override the transformation.
public SlideAnimation(View view, int duration) {
//Set the duration of the animation to the int we passed in
setDuration(duration);
//Set the view to be animated to the view we passed in
viewToBeAnimated = view;
//Get the Margin Parameters for the view so we can edit them
viewMarginParams = (MarginLayoutParams) view.getLayoutParams();
//If the view is VISIBLE, hide it after. If it's GONE, show it before we start.
hideAfter = (view.getVisibility() == View.VISIBLE);
//First off, start the margin at the bottom margin we've already set.
//You need your layout to have a negative margin for this to work correctly.
marginStart = viewMarginParams.bottomMargin;
//Decide if we're expanding or collapsing
if (marginStart == 0){
marginEnd = 0 - view.getHeight();
}
else {
marginEnd = 0;
}
//Make sure the view is visible for our animation
view.setVisibility(View.VISIBLE);
}
#Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
super.applyTransformation(interpolatedTime, t);
if (interpolatedTime < 1.0f) {
// Setting the new bottom margin to the start of the margin
// plus the inbetween bits
viewMarginParams.bottomMargin = marginStart
+ (int) ((marginEnd - marginStart) * interpolatedTime);
// Request the layout as it happens so we can see it redrawing
viewToBeAnimated.requestLayout();
// Make sure we have finished before we mess about with the rest of it
} else if (!alreadyFinished) {
viewMarginParams.bottomMargin = marginEnd;
viewToBeAnimated.requestLayout();
if (hideAfter) {
viewToBeAnimated.setVisibility(View.GONE);
}
alreadyFinished = true;
}
hideAfter = false;
}
}
EDIT: If anyone had used this code before and found that if you click on the button that starts the animation more than once before the animation was finished, it would mess up the animation from then on, causing it to always hide the view after the animation finished. I missed the reset of the hideAfter boolean near the bottom of the code, added it now.

you can do this manually by using setvisibility feature on the event onClick()
or
use this
dynamically adding two views one below other

Android: call requestLayout() after update v.layout parameter causes layout reverts back to it's original position

I have framelayout which contains two relative layouts, one is on top of the other. When user clicks a button, the one on the top move 80% off the screen to the right. Then one on the bottom becomes clickable. This is what it looks like.
FrameLayout
RelativeLayout (bottom) RelativeLayout (top)
FilterWidgets Open/close button, ListView
It's really easy to achieve on 3.0+ with the new animation api which is Property base Animation. For the pre 3.0, because animation is view based. So I end up manually modify the layout property on onAnimationEnd. The call requestLayout to make it permanent, but only to find out the layout reverts back to original position. Anybody know how to move layout permanently?
see my other post if you want to see the whole picture:
https://stackoverflow.com/questions/14541265/changecursor-cause-layout-container-of-the-listview-to-reposition
theTranslationX.addListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationEnd(Animator nullPointer) {
v.clearAnimation();
int theL = isMenuOn() ? 0 : v.getLeft() + getFilterWidth();
int theR = isMenuOn() ? v.getWidth() : v.getLeft() + getFilterWidth() + v.getWidth();
int theHeight = v.getHeight();
int theT = 0;
v.layout(theL, theT, theR, theHeight);
v.requestLayout();
}
});

This is 9 months late but try using:
yourView.layout(left,top,right,bottom); //all parameters are type int
However I don't think this is permanent, the position of the view will still be reset when you call requestLayout(), but give it a try.

Android ViewFlipper + homescreen animation

I am trying to use a ViewFlipper and make it act like the home screen(The layout will move with your finger). Check out this for an example. I want to do this with a ViewFlipper that only contains two children so the opposite view should be shown on either side of the current view depending on which way the user moves their finger. This code works but only for 1 direction at a time. This is in onTouchEvent.
case MotionEvent.ACTION_MOVE:
leftView.setVisibility(View.VISIBLE);
rightView.setVisibility(View.VISIBLE);
// move the current view to the left or right.
currentView.layout((int) (touchEvent.getX() - oldTouchValue),
currentView.getTop(),
(int) (touchEvent.getX() - oldTouchValue) + 320,
currentView.getBottom());
// place this view just left of the currentView
leftView.layout(currentView.getLeft() - 320, leftView.getTop(),
currentView.getLeft(), leftView.getBottom());
// place this view just right of the currentView
rightView.layout(currentView.getRight(), rightView.getTop(),
currentView.getRight() + 320, rightView.getBottom());
Which ever of the bottom two lines I put last that direction will work correctly but the other will not.
Here is how I set the leftView and rightView:
final View currentView = myFlipper.getCurrentView();
final View leftView, rightView;
if (currentView == meView) {
Log.d("current layout: ", "me");
leftView = youView;
rightView = youView;
} else if (currentView == youView) {
Log.d("current layout: ", "you");
leftView = meView;
rightView = meView;
} else {
leftView = null;
rightView = null;
}
Is it going to be possible to set it up so that the same view is shown on both sides of the current view?

Thanks stealthcopter
That worked here is the new code if anyone is interested.
if (touchEvent.getX() < oldTouchValue){
// place this view just right of the currentView
rightView.layout(currentView.getRight(), rightView.getTop(),
currentView.getRight() + 320, rightView.getBottom());
}else if (touchEvent.getX() > oldTouchValue) {
// place this view just left of the currentView
leftView.layout(currentView.getLeft() - 320, leftView.getTop(),
currentView.getLeft(), leftView.getBottom());
}
I also moved the setVisibility() calls to the MotionEvent.ACTION_DOWN in an attempt to get rid of some flickering of the views. This helped but I still get a bit.

I have possibly not very constructive suggestion, but if you want it to behave like a home screen, why you don't want to look at the src of that, and modify it to your needs ?

To get rid of the flickering, set setVisibility(View.INVISIBLE) in MotionEvent.ACTION_DOWN. The default value is "GONE" on a view. That means that you can not set Layout() on a view until it's either "VISIBLE" or "INVISIBLE". So in three steps:
Set Visibility to INVISIBLE on the View
Set Layout() on the View
Set Visibility to Visible on the View

If I understand your request, this effect should now be implemented using a View Pager
Looks like this: