Detect if some part of the view is NOT visible?

Question

Is it possible to detect if some part of the view is not visible on the screen?

This is used in a situation that view's width/height is bigger that its parent's width/height.

EDIT

I get that the height of a view is 0. Does anyone knows why? I fetch the height in onCreate.

LinearLayout lin = (LinearLayout) findViewById(R.id.linear_layout);
final int layoutHeight = lin.getHeight();
Toast.makeText(this,"LinLay height: "+layoutHeight,Toast.LENGTH_SHORT).show();
...
        button = (Button) findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {
                int displayTextWidth = textView.getWidth();

                if (displayTextWidth <= layoutHeight) {
                    textView.setTextSize(textView.getTextSize() + 1);
                }
            }
        });

The height is 0 in onCreate because it was not drawn yet. Read more at: http://stackoverflow.com/questions/3779173/determining-the-size-of-an-android-view-at-runtime — Daniel Novak, Jun 28 '11 at 12:11

score 2 · Accepted Answer · edited May 23 '17 at 11:58

2

You could get the view's width and height by calling View.getWidth() and View.getHeight(), then get the device dimensions by these means: How do I get a device's maximal width and height in android

Then compare the two, and if the view's bounds are larger than your device's bounds, then some parts of the view are not visible.

In response to comments:

    textView.post( new Runnable() {

    @Override
    public void run() {

        int displayTextWidth = textView.getWidth();

        // Code that uses width here...
    }
});

edited May 23 '17 at 11:58

Community

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answered Jun 27 '11 at 17:27

Jason Robinson

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If I measure some view's height in onCreate, I see that the view's height is 0. I will edit the question and add the code for your review. – sandalone Jun 28 '11 at 09:54
1

use `textView.post(Runnable)` and get the height inside that `Runnable`. Should do the trick. – Jason Robinson Jun 28 '11 at 19:58
Should I use the `Runnable` inside `button.setOnClickListener` or somewhere else? – sandalone Jun 29 '11 at 13:08
Thanks. I'll try this and let you know of result. – sandalone Jun 29 '11 at 17:08

Detect if some part of the view is NOT visible?

1 Answers1