CODEWITHSUNDEEP
androidandroid-layoutandroid-linearlayoutandroid-view
Rarw
Rarw

Reputation: 7663

Effect of setting parent view visiblity on its children

This question arises from having to show/hide different views dynamicly. View's have 3 visibility settings - visible, invisible, and gone. If you have a parent view, for example a LinearLayout, that has several child views (doesn't matter what they are) is setting the visibility of the parent the same as seting the visiblity on all the children independently? For example if I say

LinearLayout container = (LinearLayout) findViewById(R.id.layout_1);
container.setVisiblity(View.GONE);

Is that the same as finding each individual child view and setting all those visiblities to View.GONE? What if the parent was not View.GONE but View.INVISIBLE? Are all the children still drawn but just not seen?

Upvotes: 23

Views: 17310

Answers (3)

Geobits
Geobits

Reputation: 22342

The effect is the same, but it does not actually set the visibility of all the children. It just won't draw them.

For instance:

  1. Set child to GONE (parent is visible, child is gone)

  2. Set parent to GONE (both gone)

  3. Set parent to VISIBLE (parent visible, child still gone, since child was explicitly set before)

  4. Set child to VISIBLE (both visible)

Any time a view is INVISIBLE, it won't draw it or its children. If it's GONE, it also won't reserve any layout space for them. If you check the child's getVisibility() though, you'll see that it's still set to whatever it was before, even if it's not being drawn.

Upvotes: 40

vareste
vareste

Reputation: 445

Use below recursive function to make your child views visible or gone.
First argument is your parent view and second argument decides if you want childs of parent view visible or gone. true = visible false = gone

private void layoutElemanlarininGorunumunuDegistir(View view, boolean gorunur_mu_olsun) {
    ViewGroup view_group;
    try {
        view_group = (ViewGroup) view;
        Sabitler.konsolaYazdir(TAG, "View ViewGroup imiş!" + view.getId());
    } catch (ClassCastException e) {
        Sabitler.konsolaYazdir(TAG, "View ViewGroup değilmiş!" + view.getId());
        return;
    }

    int view_eleman_sayisi = view_group.getChildCount();
    for (int i = 0; i < view_eleman_sayisi; i++) {
        View view_group_eleman = view_group.getChildAt(i);
        if (gorunur_mu_olsun) {
            view_group_eleman.setVisibility(View.VISIBLE);
        } else {
            view_group_eleman.setVisibility(View.GONE);
        }
        layoutElemanlarininGorunumunuDegistir(view_group_eleman, gorunur_mu_olsun);
    }
}

Upvotes: -2

athor
athor

Reputation: 6928

Yea you are correct on all points :)

Setting the layouts visibility to GONE will hide all children. Setting the layouts visibility to INVISIBLE will make all children invisible but still drawn and occupy space.

Upvotes: 0

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