I have many activities with a scrollview inside a tablelayout. However, it is necessary a small design change, so I have to put a black transparent view over the whole screen from the top to the bottom. Is it possible to do it in the tablelayout or the scrollview?
RelativeLayout allows for easy overlapping of views. You'll have to adjust the existing views in your app because it doesn't do anything automatically.
EDIT:
A quick way to do this would be to take your existing view (the ScrollView) that is already organized and put it in a top-level RelativeLayout. Then, all you have to do is add new view inside the RelativeLayout with the width and height both set to MATCH_PARENT. The result should be the black transparent view will be visible over the ScrollView.
I normally use FrameLayout to achieve any kind of 'layering' of views.
<FrameLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
//your existing layout
<View
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#33000000" />
</FrameLayout>
As DeeV said, you can probably use RelativeLayout in a similar way, but you might have to set additional attributes on its children to achieve this.
Related
Related question. Answer: RelativeLayout can't do it. I'm asking how to do it anyway, with not just RL, or with something else.
General story: you have a complex layout that would be difficult to adjust, and along comes a request for something to be added, aligning with a nested view.
What is the best approach? A popup with a custom style? (not familiar with those yet)? Spending days changing the whole hierarchy to a single RelativeLayout? A custom Layout class as wrapper?
AbsoluteLayout (deprecated) or FrameLayout with programmatically changed LayoutParams or margins? (this I'd rather avoid, I prefer not to touch onMeasure, etc)
Simplified example (no relation to pic above):
LinearLayout defines relative heights of the elements. I don't know to do it with RelativeLayout.
anExpandableView is something to be animated as sliding from under someBar (here; full-width, but perhaps it may need to align its width, as well as vertical position).
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:animateLayoutChanges="true">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<include
android:id="#+id/topStuff"
layout="#layout/incl_topstuff"
android:layout_width="match_parent"
android:layout_weight="7"
android:layout_height="0dip" />
<include
android:id="#+id/someBar"
layout="#layout/incl_filters_and_stuff"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<include
android:id="#+id/bottomStuff"
layout="#layout/incl_bottomstuff"
android:layout_width="match_parent"
android:layout_height="0dip"
android:layout_weight="10" />
</LinearLayout>
<include
android:id="#+id/anExpandableView"
layout="#layout/incl_filters"
android:visibility="gone"
android:layout_below="#id/someBar"/>
</RelativeLayout>
I know SO has an aversion to general questions, but I don't want an ad-hoc solution. I am asking what to do in cases which would be solved if only a wrapping RelativeLayout would allow alignment to a view that is not a direct sibling.
Putting it simply, RelativeLayout can only measure and layout it's direct children based on each other, but I guess you already knew that.
The only general solution would be to implement your own custom Layout class, which I wouldn't recommend. If I had to guess why RelativeLayout does not traverse the entire layout hierarchy at it's level and below, it's probably for performance reasons.
Unfortunately if you're using RelativeLayouts and LinearLayouts and you want views to be dependent on each other you have to pick one approach and stick to it, either the flat hierarchy of RelativeLayout, or the nested one of LinearLayout.
Based on your example, as far as I know, there is no way to implement weighted views with a RelativeLayout, so you're stuck with using a LinearLayout.
The easiest way to do what you want is to inflate your expandableView in code, align it with the bottom of the RelativeLayout, set it's height and position based on bottomStuff, and animate from there.
If you really want to do it in xml, I can think of one somewhat hacky, ad-hoc approach, but which can can be generalized to mirroring the measurement and layout of any hierarchy with a bit of work.
Create a parallel but invisible LinearLayout that is a sibling of the first one. Give it an empty view with weight 7 on top, an invisible copy of someBar in the middle, then your expandable view under that with weight 10. To have it slide up, either animate the height of the invisible someBar and the weight of the empty view on top towards 0, or remove them/set them to gone and set animateLayoutChanges on your LinearLayout.
This is what is causing me many problems:
<RelativeLayout
android:id="#+id/galleryLayout"
android:layout_width="match_parent"
android:layout_height="180dp"
android:background="#color/white">
<android.support.v4.view.ViewPager
android:id="#+id/imageViewPager"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true" />
<com.viewpagerindicator.CirclePageIndicator
android:id="#+id/circlePageIndicator"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:padding="#dimen/padding_middle"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"/>
</RelativeLayout>
Right now this code kind of works only because I've set RelativeLayout's height to 180dp but I don't want to have it this way. I want the whole thing to have height according to ViewPager's child.
There are exactly 2 problems if I set RelativeLayout's height to WrapContent.
Problem 1
ViewPager will expand throughout the whole screen. It just doesn't respect it's wrap_content height attribute. But I've partially solved that with this answer. I'd still appreciate if there's a better solution though.
Problem 2
I want have CirclePageIndicator on the bottom of it's parent (RelativeLayout) so I've added attribute layout_alignParentBottom="true" but now because of this, the RelativeLayout will expand throughout the whole screen for some reason.
So what I'm trying to have is a RelativeLayout which wraps around ViewPager which wraps around it's child. The child is downloaded from web so I can't pre-set it. And on the bottom of that RelativeLayout, I want to have a ViewPagerIndicator.
As for the problem 1 you solved the issue correctly, ViewPager will not wrap its children by default.
As for the second problem, this is a normal RelativeLayout behaviour. If you set its height to wrap_content and add two children, one with layout_alignParentTop="true" and second one with layout_alignParentBottom="true", they will stretch your layout height-wise.
What you should do is: ask yourself if you really need RelativeLayout. If you've provided the whole layout of yours I don't see a need for RelativeLayout (its costly). Vertical LinearLayout would do just fine. If you decide that you really need RelativeLayout, try changing your Indicator's rule from layout_alignParentBottom="true" to android:layout_below="#+id/imageViewPager".
I want to scroll the background in android. I have a scrollview which has many views. I need to implement a way wherein i need to scroll only the background while adding the views. I came across many forums but none of them are very clear. Please give an idea or references to implement it. To give more idea for what i am looking for is, Just consider a bike game wherein the background road image moves while riding the bike. I just need similar implementation while scrolling the screen.
Maybe you could do like this:
RelativeLayout as the parent
ScrollView with your image set as background
Then the other views, but outside of the ScrollView and inside of the RelativeLayout.
EDIT:
<RelativeLayout
android:id="#+id/relParent"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<OtherViews />
<ScrollView
android:id="#+id/scrlParent"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#drawable/yourbackground">
</ScrollView>
</RelativeLayout>
I think that something like this might work. You see, the RelativeLayout is the parent. Then comes your other views, on the top of your ScrollView. Then, after your other views tag, comes the ScrollView, with only a background. I'm not sure if a background tag would work, so maybe you should remove the android:background="#drawable/yourbackground" and put an ImageView inside of the ScrollView.
I would like to place a layout on the bottom of a LinearLayout, but I can't seem to get it to work. I know that I can use RelativeLayout to do this, but I should be able to use LinearLayout, shouldn't I?
EDIT: Actually this is more confusing than I thought. The layout below is simplified. In reality, I'm using fragments on a pre-3.0 device, with the compatibility layer.
I used Hierarchy Viewer to examine what's going on, and found that an android.support.v4.app.NoSaveStateFrameLayout was added to my layout, and that layout has layout_height set to wrap_content. That seems to be what's causing my problem, but I haven't yet figured out how to fix it.
Specifically, why doesn't this work? Shouldn't the layout_gravity place it at the bottom?
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
... stuff here ...
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:orientation="horizontal">
... more stuff here ...
</LinearLayout>
</LinearLayout>
BTW, changing layout_height to fill_parent or setting layout_weight don't seem to work either. I just want to better understand what is going on, because clearly I'm missing something important. Thanks.
First of all nice question.
Android behaves we can say weird in the situation like this.
if you have selected your parent linear layout's orientation horizontal then you can set its child component at bottom by setting its layoug_gravity=bottom. suppose you have added 2 text views in that horizontal linear layout and second textview's layout_gravity is bottom then it will set to bottom but it work like it is set at bottom in other column then the first text view. NOTE : you can set textview's layout_gravity = "left" or "right" when its parent linearlayout is horizontal but you cant see its result.
Oppositely, if you have selected parent linearlayout's orientation vertical then you can set its child component at left or right by using layout_gravity. but the second textview will shown in you can say next row with left or right gravity as you have set. NOTE you can set textview's layout_gravity = "top" or "bottom" when its linear layout is vertical but you can not see its result.
Try to make sample xml design as i have stated above so you get better idea.
Strange but True!!! Try to understand this behavior. :)
Just add space between what you want at the bottom and all the rest:
<Space
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"/>
So I resolved the problem. It's a two-part solution:
First, the way to do this without using LinearLayout is to provide weight to the element above so that it takes up all of the empty space. BTW, you can see this example in the API demos: http://developer.android.com/resources/samples/ApiDemos/res/layout/linear_layout_3.html
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
... stuff here ...
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:weight="1"/>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
... more stuff here ...
</LinearLayout>
</LinearLayout>
This by itself didn't solve my problem, as I had a NoSaveStateFrameLayout with layout_width="wrap_content" as a parent view, and so I needed to get that fixed first. I'm using code based on the wonderful Google I/O App, and when I searched the code for NoSaveStateFrameLayout, I found this:
// For some reason, if we omit this, NoSaveStateFrameLayout thinks we are
// FILL_PARENT / WRAP_CONTENT, making the progress bar stick to the top of the activity.
mRootView.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT,
ViewGroup.LayoutParams.FILL_PARENT));
Thanks for an awesome comment Google!!! I added this into my source and everything worked great!
The moral of the story: Hierarchy Viewer and comments are your friends.
LinearLayout will just stack things as they are placed in there. Since it is vertical, it will keep placing items one after the next in a vertical manner. Can you change the android:gravity of the linearLayout and not the layout_gravity of the nested one and see if that works.
RelativeLayout of course should be the first way but you stated you didnt want to do that. Is there reason for that?
It could be that, as per https://stackoverflow.com/a/13366783/513038, you need to set the parent LinearLayout to have android:baselineAligned="false". Worked in my case.
I need to implement the layout as in the picture. Parent and Sibling are in a vertical LinearLayout. So I need to make a child view to overlap it's parent. Can I do that in android?
If:
sibling is a sibling of parent
parent is a ViewGroup
and you really want child to be a child of parent
then maybe you could consider using android:clipChildren set to false on parent.
I was actually just looking at an example of a FrameLayout that had a TextView overlaid on top of an ImageView. So, there are obviously multiple ways to get it done. Your next question might be which one is best ... to that I have no idea, but here's a guy that might:
http://www.curious-creature.org/2009/03/01/android-layout-tricks-3-optimize-part-1/
Just contain them all within a RelativeLayout, and remember the draw order is top to bottom, so put the top most view on the bottom of the XML definition.
If you use a RelativeLayout you should have no problem achieving this effect. By default it will stack all of its children on top of each other in the top left corner if you don't supply them with android:layout parameters. So it will definitely support overlapping children. You'd just have to figure out what the best way to tell it where the child should go on the screen relative to something else.
There are at least two layouts that can do that. AbsoluteLayout and RelativeLayout. I suggest that you put your views in a RelativeLayout and add them with LayoutParams that specify their offset form the top and left of the parent:
RelativeLayout.LayoutParams rlp;
label = new TextView(ctx);
label.setBackgroundColor(0x00000000);
label.setTextColor(0xFF7ea6cf);
label.setTextSize(13);
label.setGravity(Gravity.LEFT);
label.setText("Examples:\n- Fentanyl\n- Dilaudid 2 mg PO q 4 hours prn moderate pain");
rlp = new RelativeLayout.LayoutParams(LayoutParams.FILL_PARENT,100);
rlp.topMargin=189;
rlp.leftMargin=30;
rlp.rightMargin=30;
rlParent.addView(label,rlp);
In my case, I have to set android:clipCildren to be false on the parent of parent.
i.e.
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipChildren="false"
android:id="#+id/parent1">
<FrameLayout
android:id="#+id/parent2"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margin="64dp"
android:background="#android:color/holo_blue_bright">
<View
android:id="#+id/This_is_the_view_I_want_to_overlap_parent2"
android:layout_width="160dp"
android:layout_height="80dp"
android:layout_gravity="top|start"
android:layout_marginTop="-40dp"
android:background="#000000" />
</FrameLayout>
</FrameLayout>