When I add element into a layout(in this case a LinearLayout), there is a white space on the two side of the element, but the attribute layout_width is "match_parent". Why?
Here's a screenshot:
http://s32.postimg.org/o4vr8kzbp/device_2016_07_30_001720.png
The code:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="500dp"
android:background="#color/blue"
android:orientation="vertical">
</LinearLayout>
</LinearLayout>
I found this lines somewhere on this site and it might be worth checking;
This is possibly because you are using the auto-generated layout files in Android Studio when starting a new project, which by default adds a margin of 64dp to tablet screens (the value found inside values-w820dp\dimens). – PPartisan 6 hours ago
Maybe you should check your layout's parent's layout in the host activity for one more time.
It is possible that the root layout does not fill the parent or that the child you are adding has a margin, to know exactly whats going on use the android tool called DDMS or Android Device Monitor (you can launch it from Eclipse or Android Studio) then click on Dump View Hierarchy. This will give you details on the size, padding, margin and other properties of every view on the view hierarchy
You should to check your code, may be you update margins of layout at your classes.
And try to check layouts of home activity, may be they are contains layout_marginLeft(layout_marginStart) and layout_marginRight(layout_marginEnd).
Also parent layouts may contains any white views on the sides or parameter layout_weight with specific value.
Related
I was going through sample code for media effects in Android samples for API level 23 and found an unusual value (0.93) being assigned to layout_weight for one of the views contained in a LinearLayout.
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<android.opengl.GLSurfaceView
android:id="#+id/effectsview"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="0.93"/>
Since the layout is not having any other childviews other than android.opengl.GLSurfaceView , does this value (or android:layout_weight itself) has any significance? I tried to change this value randomly and as expected it did not have any impact on layout.
Edit : Added sample code link
If you don't have any more views with weigths nothing would happen. It's depends on it what android:layout_weight exactly does:
With layout_weight you can specify a size ratio between multiple views. E.g. you have a MapView and a table which should show some
additional information to the map. The map should use 3/4 of the
screen and table should use 1/4 of the screen. Then you will set the
layout_weight of the map to 3 and the layout_weight of the table
to 1.
To get it work you also have to set the height or width (depending on your orientation) to 0px.
Read this: What does android:layout_weight mean?
So according to your question if you don't have more views with weight, you can also delete this line of code.
EDIT: Thanks for the link. Now I know the reason of this attribute.
Mysterious fragment_media_effects.xml layout file might be already inherited in activity_main.xml, where two others views has also weights. If I am right the value of this view should change, not in Layout Editor, but when you open an app with this fragment.
I've been playing around with Android lately and I've run into a problem building UIs. More precisely, I'm pretty sure when I was building the first layout, the layout editor in Eclipse adjusted the visible area so when I added new widgets, it stretched in height to display them.
Now I have a problem that whenever the widgets fill the area, it's impossible for me to properly lay them out since the preview window displays only the height of a single screen, even if it's a simple LinearLayout with a bunch of textviews to fill about 2 screen heights.
Also, I'm using the latest stable Eclipse and ADT plugin, target platform is 2.2.
EDIT
What I meant was that the editor doesn't display the elements that don't fit inside a single screen height and clips the stuff (see the image to see how it clips, there are actually 2 more textviews that are clipped totally) which makes impossible to build UIs that are taller that a single screen height.
That's normal there is a clipping occuring. I just tested it on my eclipse and I have the same behavior than you.
If what you want to achieve is creating a layout bigger than your screen size, you should use scroll views (and insert your initial layout in it):
<?xml version="1.0" encoding="utf-8"?>
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
isScrollContainer="true" >
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/exampleView"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center_horizontal"
android:orientation="vertical" >
...
Once in scroll mode, the layout will auto adjust.
Try this:
Hope this helps. If this hasn't solved your problem, then please explain your question again in different words, because that's how I understood it.
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.
My current layout displays activity that is not full screen (that's OK).
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="100dip"
android:layout_height="200dip" >
<TextView android:layout_height="wrap_content" android:id="#+id/textView1"
android:layout_width="fill_parent" android:text="#string/hello"></TextView>
I also added android:theme="#android:style/Theme.Translucent" to manifest for my activity.
My 200x100dip activity now shows in the upper left corner. How can i specify position of my linear layout (or my activity)?
You can use either FrameLayout or RelativeLayout as outer most layout for this. Ant then use absolute position in dp or android:layout_centerInParent or similar.
I believe your Activity´s outmost layout element (LinearLayout) will be placed in a FrameLayout that is the parent given from Android. I suggest you let your outmost layout match_parent/fill_parent in layout_height and _width and then center the content inside it with gravity="center" on your outmost layout. By letting the outmost layout being transparent and not catch click element it will appear as layout in the middle where elements behind is visible. If Im correct guessing that's what you want to achieve here.
put that layout in another absolute layout in which you use android:layout_width="fill_parent" and android:layout_height="fill_parent" the other thing you can do is to use this: http://www.droiddraw.org/
you can move your elements around manually with that and it will give you the XML code that is used to do that. I found it very useful in laying out XML in android.
I'm using Eclipse Helios 3.6.2 for Android development and whenever I design a layout in the graphical layout mode (not the XML layout), I can't see the entire content of a ScrollView in the graphical layout.
Specifically, when I'm using a ScrollView and the height of the ScrollView exceeds the height of the content view area (i.e., the phone screen visible in the graphical layout mode), I am not able to see the items that I have at the bottom of the screen.
In Eclipse Helios 3.6.1 there was an option called "expand to fit"; whenever I used to click on it, the phone screen increased in size to encompass all the elements that I had added. How do i achieve the same thing in 3.6.2?
There's no way to scroll the content inside the Android Layout Editor. What you can do, though, is create a new device simulation with a huge height, so you can see what is hidden in the ScrollView.
To do so, go to the dropdown menu below "Editing config" ang choose "Custom..." (top-left corner of the Android Layout Editor). Select one of your preferred resolutions (mine is 3.7in WVGA) and hit "Copy". The copied resolution will appear in the "Custom" group in the bottom of the list.
Choose your new configuration and hit "Edit...". In there, you can select the "Screen Dimension" property and change the value. I created a resolution 2000x480 (portrait). This way, I can see the whole content inside the ScrollView.
Hope it helps.
Use an included layout for the scrollview.
Move the entire scrollview layout in a separated file (ie: my_scrollview.xml).
<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
...
</ScrollView>
The layout editor will then display the entire scrollview.
In the main layout use in place of the scrollview something like:
<include layout="#layout/my_scrollview" />
There was a button that allow to remove the clipping generated in a scroll view and show all the views that you have inside it.
In later sdk versions the button is removed, and the view mode is triggered if the scroll view is the root element of the view, so my solution when this doesn't happen (because you have a relative layout with some buttons over the view for example) is extracting the scrollview to it's own view, and including it in the original layout with an include tag.
My quick fix.
In the upper right corner of the graphic layout window you will see a drop down menu that shows what minimum version of android you are creating for. Make sure you have it set to at least android 2.1. I had an app at 1.6 and i had the same issue you have. swapped minimum build platform to 2.1 and it was magic.
Hope this helps.
If use Relative layout, you can use layout_marginTop negative, like that:
<ScrollView
android:id="#+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginTop="-500px"
android:layout_alignParentLeft="true"
android:layout_below="#+id/linearLayout" >
Increase the layout_marginTop to move scrollview.
The drop-down on the left (under the text "Editing config: ...") allows you to change the simulated screen size in the graphical layout. Perhaps that is what you are looking for.
Just click on the Config window of the Graphical Layout and click on the preview for all screen sizes and u will be able to see your scroll
Use the android:scrollY in the ScrollView child and remove it before publishing.
<ScrollView ... >
<LinearLayout ...
scrollY="300dp">
</LinearLayout>
</ScrollView>