Android: why setVisibility(View.GONE); or setVisibility(View.INVISIBLE); do not work
I want my DatePicker
and the button to be invisible in the b开发者_如何学运维egining. And when I press my magic button I want to setVisibility(View.Visible);
The problem here is when I setVisibility(View.GONE)
or setVisibility(View.INVISIBLE)
nothing changes and the component is still visible.
final DatePicker dp2 = (DatePicker) findViewById(R.id.datePick2);
final Button btn2 = (Button) findViewById(R.id.btnDate2);
dp2.setVisibility(View.GONE);
dp2.setVisibility(View.INVISIBLE);
btn2.setVisibility(View.GONE);
btn2.setVisibility(View.INVISIBLE);
btn2.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
TextView txt2 = (TextView) findViewById(R.id.txt2);
txt2.setText("You selected " + dp2.getDayOfMonth()
+ "/" + (dp2.getMonth() + 1) + "/" + dp2.getYear());
}
});
I see quite a few things wrong. For starters, you don't have your magic button defined and there is no event handler for it.
Also you shouldn't use:
dp2.setVisibility(View.GONE);
dp2.setVisibility(View.INVISIBLE);
Use only one of the two. From Android documentation:
View.GONE This view is invisible, and it doesn't take any space for layout purposes.
View.INVISIBLE This view is invisible, but it still takes up space for layout purposes.
In your example, you are overriding the View.GONE
assignment with the View.INVISIBLE
one.
Try replacing:
final DatePicker dp2 = new DatePicker(this)
with:
DatePicker dp2 = (DatePicker) findViewById(R.id.datePick2);
Similarly for other widgets:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
final DatePicker dp2 = new DatePicker(this);
final Button btn2 = new Button(this);
final Button magicButton = new Button(this);
final TextView txt2 = new TextView(TestActivity.this);
dp2.setVisibility(View.GONE);
btn2.setVisibility(View.GONE);
btn2.setText("set Date");
btn2.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
txt2.setText("You selected "
+ dp2.getDayOfMonth() + "/" + (dp2.getMonth() + 1)
+ "/" + dp2.getYear());
}
});
magicButton.setText("Magic Button");
magicButton.setOnClickListener(new View.OnClickListener()
public void onClick(View arg0) {
dp2.setVisibility(View.VISIBLE);
btn2.setVisibility(View.VISIBLE);
}
});
ll.addView(dp2);
ll.addView(btn2);
ll.addView(magicButton);
ll.addView(txt2);
setContentView(ll);
}
Today I had a scenario, where I was performing following:
myViewGroup.setVisibility(View.GONE);
Right on the next frame I was performing an if
check somewhere else for visibility state of that view. Guess what? The following condition was passing:
if(myViewGroup.getVisibility() == View.VISIBLE) {
// this `if` was fulfilled magically
}
Placing breakpoints you can see, that visibility changes to GONE
, but right on the next frame it magically becomes VISIBLE
. I was trying to understand how the hell this could happen.
Turns out there was an animation applied to this view, which internally caused the view to change it's visibility to VISIBLE
until finishing the animation:
public void someFunction() {
...
TransitionManager.beginDelayedTransition(myViewGroup);
...
myViewGroup.setVisibility(View.GONE);
}
If you debug, you'll see that myViewGroup
indeed changes its visibility to GONE
, but right on the next frame it would again become visible in order to run the animation.
So, if you come across with such a situation, make sure you are not performing an if
check in amidst of animating the view.
You can remove all animations on the view via View.clearAnimation()
.
You can think it as a CSS style visibility & display.
<div style="visibility:visible; display:block">
This is View.VISIBLE : Content is displayed normally.
</div>
<div style="visibility:hidden; display:block">
This is View.INVISIBLE : Content is not displayed, but div still takes up place, but empty.
</div>
<div style="display:none">
This is View.GONE : Container div is not shown, you can say the content is not displayed.
</div>
First see your code:
dp2.setVisibility(View.GONE);
dp2.setVisibility(View.INVISIBLE);
btn2.setVisibility(View.GONE);
btn2.setVisibility(View.INVISIBLE);
Here you set both visibility to same field so that's the problem. I give one sample for that sample demo
In my case I found that simply clearing the animation on the view before setting the visibility to GONE
works.
dp2.clearAnimation();
dp2.setVisibility(View.GONE);
I had a similar issue where I toggle between two views, one of which must always start off as GONE
- But when I displayed the views again, it was displaying over the first view even if setVisibility(GONE)
was called. Clearing the animation before setting the view to GONE
worked.
View.GONE This view is invisible, and it doesn't take any space for layout purposes.
View.INVISIBLE This view is invisible, but it still takes up space for layout purposes.
dp2.setVisibility(View.GONE);
dp2.setVisibility(View.INVISIBLE);
btn2.setVisibility(View.GONE);
btn2.setVisibility(View.INVISIBLE);
This is for someone who tried all the answers and still failed. Extending pierre's answer. If you are using animation, setting up the visibility to GONE
or INVISIBLE
or invalidate()
will never work. Try out the below solution.
`
btn2.getAnimation().setAnimationListener(new Animation.AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {
}
@Override
public void onAnimationEnd(Animation animation) {
btn2.setVisibility(View.GONE);
btn2.clearAnimation();
}
@Override
public void onAnimationRepeat(Animation animation) {
}
});
`
View.GONE makes the view invisible without the view taking up space in the layout. View.INVISIBLE makes the view just invisible still taking up space.
You are first using GONE and then INVISIBLE on the same view.Since, the code is executed sequentially, first the view becomes GONE then it is overridden by the INVISIBLE type still taking up space.
You should add button listener on the button and inside the onClick() method make the views visible. This should be the logic according to me in your onCreate() method.
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_setting);
final DatePicker dp2 = (DatePicker) findViewById(R.id.datePick2);
final Button btn2 = (Button) findViewById(R.id.btnDate2);
final Button btn3 = (Button) findViewById(R.id.btnVisibility);
dp2.setVisibility(View.INVISIBLE);
btn2.setVisibility(View.INVISIBLE);
bt3.setOnClickListener(new View.OnCLickListener(){
@Override
public void onClick(View view)
{
dp2.setVisibility(View.VISIBLE);
bt2.setVisibility(View.VISIBLE);
}
});
}
I think this should work easily. Hope this helps.
I was also facing the same issue, if suppose that particular fragment is inflated across various screens, there is a chance that the visibility modes set inside the if statements to not function according to our needs as the condition might have been reset when it is inflated a number of times in our app.
In my case, I have to change the visibility mode in one fragment(child fragment) based on a button clicked in another fragment(parent fragment). So I stored the buttonClicked boolean value in a variable of parent fragment and passed it as a parameter to a function in the child fragment. So the visibility modes in the child fragments is changed based on that boolean value that is received via parameter. But as this child fragment is inflated across various screens, the visibility modes kept on resetting even if I make it hidden using View.GONE.
In order to avoid this conflict, I declared a static boolean variable in the child fragment and whenever that boolean value is received from the parent fragment I stored it in the static variable and then changed the visibility modes based on that static variable in the child fragment.
That solved the issue for me.
I had the same problem once. Calling invalidate after changing visibility almost always works, but in some cases it doesn't. I had to cheat and set the background to a transparent image and set the text to "".
Because you set visibility either true or false.
try that
setVisible(0)
to visible true .
and setVisible(4)
to visible false.
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