I recently tried to position an imageview's x and y coordinates with no luck, it seems there is no way to do it in Gingerbread. I then decided to try out paddings and margins, but when I set them, it shrinks my imageview. I set a left padding of 250dp and image view became tiny. The layout_height and width are set to wrap_content. I'm not sure what's going on. Does anyone know why setting a padding/margin would shrink an imageview?
You're confusing margin and padding. Margin is the area outside of your view, while padding affects the content inside your margin.
If you set padding, then it is going to affect your available content area, and assuming you have a ScaleType set, it's going to shrink your image down to fit the available space.
Now, you say you've tried margins, but margins will do exactly what you're asking.
For example, if you wanted an ImageView placed 10dp from the top-left corner, you can do something like this:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<ImageView
android:id="#+id/my_image_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_marginTop="10dp"
android:layout_marginLeft="10dp"
android:src="#drawable/my_image_id"
/>
</RelativeLayout>
Keep in mind that this places it 10dp with respect to the parent boundaries. If your parent layout also has padding, then that will affect your content placement.
if by shrink you mean the picture's ratio is messed then you should use
android:scaleType="centerInside"
this will prevent the ratio from changing
Related
I have a image view inside of a relative view, as per code below
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal">
<ImageView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:src="#drawable/maintenance_banner"
android:layout_alignParentTop="false"
android:layout_margin="0dp"
android:padding="0dp"/>
</RelativeLayout>
what i don't understand is the gaps at the top & bottom, as I have set both height to wrap_content, the gaps shouldn't be part of the content, only the imageview it self isn't it? Or does it means the gaps are part of the image view it self? but i set the padding to 0. also, for some reason I can get ride of them by setting scale type.
The image probably has another aspect ratio then your imageView.
Try to set the android:scaleType to centerCrop or whatever else does work for you.
The default scale type is: FIT_CENTER and FIT_XY for buttons.
Hope this helps
EDIT: Sorry I haven't seen the wrap content.
From the screenshot it looks like you have other views below, are you including this layout file into another one?
Cheers
I have a complex xml layout with part of it being:
...
<FrameLayout
android:id="#+id/parent"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_gravity="center_horizontal"
android:layout_marginLeft="30dp"
android:layout_marginRight="30dp"
android:layout_weight="1" >
<ImageView
android:id="#+id/flexible_imageview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:adjustViewBounds="true" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:background="#drawable/gradient"
android:orientation="vertical"
android:paddingBottom="16dp"
android:paddingLeft="16dp"
android:paddingTop="8dp" >
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
</FrameLayout>
...
The height of the FrameLayout #+id/parent must be determined at runtime because it is displayed above many other views, and they must be shown in the layout. This way the FrameLayout fills the remaining space perfectly (using height="0dp" and weight="1" properties).
The ImageView #+id/flexible_imageview receives an image from the network, and it always shows with the correct aspect ratio. This part is already ok as well. This View is the largest and should determine the size of the FrameLayout #+id/parent.
The problem is that when the image is drawn, the width of the FrameLayout #+id/parent is not adjusted to wrap and be the ImageView #+id/flexible_imageview as it should be.
Any help is appreciated.
-- update --
I've updated the layout to clarify some of the missing parts, and to add the reasoning behind all of it.
What I want is to have an Image (ImageView #+id/flexible_imageview) with unknown dimensions to have, on top of it, a gradient and some text on top of the gradient. I can't set the FrameLayout #+id/parent dimensions to both wrap_content because there is more Views after this Image that must be shown. If there's not enough space in the layout, the Image (ImageView #+id/flexible_imageview) is reduced until it all fits in the layout, but it should maintain its aspect ratio, and the gradient/texts on top of it.
The #drawable/gradient is just:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" >
<gradient
android:angle="270"
android:endColor="#aa000000"
android:startColor="#00000000" />
</shape>
-- update 2 --
I added two images below to demonstrate what's happening, and what should happen:
Bug:
Correct:
If would help if you explained more about what you are trying to accomplish in your layout (not the layout itself but what should the user see on the screen and what are the other elements in the layout).
A FrameLayout with multiple children is usually a "code smell". Usually, FrameLayouts should have only one child element. So this makes me wonder whether there is something wrong with your design.
-- Edit --
If I understand correctly, you are trying the framelayout to wrap the content of the image but at the same time match the space left from the other layout views before/after the frame layout.
What is the parent view/layout of the frame layout?
I see a couple of problems with this design or your explanation:
You have framelayout width set to match parent, but you want to wrap the content of the image.
You want the imageView to be reduced but you are not taking into account the text views in the linear layout. You have them set to wrap content. So when the fame layout is small, you will not see all the textviews. (Unless you are resizing them as well somehow).
Sorry if this isn't helpful enough but it's difficult to understand what you are trying to accomplish with this layout. A sample use-case would help in providing you a better recommendation.
When a dimension (width / height) is MeasureSpec.EXACTLY adjustViewBounds will not effect it.
In your case, having android:width="match_parent" ensures that the image view is the size of the parent, regardless of adjustViewBounds.
It works to begin with because the height is wrap_content - the height is adjusted when the image is scaled to fill the width.
When you override the height to fit everything on the screen (this may not be a great idea to begin with), the width is still matching the parent and doesn't get adjusted. However, because the scale type is ScaleType.FIT_CENTER the image is scaled and positioned so that the entirety of it fits in the bounds of the ImageView (and centred.. hence the name).
If you turn on the debug option for drawing layout bounds, or look at your app using hierarchyviewer, you'll see that the image view is still matching the width of its parent.
There are a couple of ways you could do what you want.
Since you're already manually calculating the height, setting the width shouldn't be that hard.
Drawable drawable = imageView.getDrawable();
if (drawable != null && drawable.getIntrinsicWidth() > 0 && drawable.getIntrinsicHeight() > 0) {
int height = // however you calculate it
int width = height / (getDrawable().getIntrinsicHeight() / getDrawable().getIntrinsicWidth());
}
You might also get away with
<ImageView
android:id="#+id/flexible_imageview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:adjustViewBounds="true"
android:minWidth="9999dp" />
Even if this works, you probably wouldn't be able to use it in a horizontal LinearLayout using weights any more (for example, if you wanted a landscape variant of the layout), or a number of other scenarios.
i have this problem frequently, and I refuse to believe that it can't be solved without creating a custom layout:
How do you align a view with an ImageView that get scaled to match it's parent bounds but keeps the aspect ratio ( scale type is anything but fitXY ). I was under the assumption that f you set adjustViewBounds to true, the view bounds get adjusted to match the actual size of the image ("Set this to true if you want the ImageView to adjust its bounds to preserve the aspect ratio of its drawable."). But that is not the case. And it doesn't make and difference if the image has to get scaled up or down to fit its bounds.
Take a look at this layout:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
>
<ImageView
android:id="#+id/imageView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:adjustViewBounds="true"
android:scaleType="fitCenter"
android:src="#drawable/square" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignRight="#+id/imageView1"
android:layout_alignTop="#+id/imageView1"
android:text="#string/hello_world" />
</RelativeLayout>
This layout looks like this:
As you can see the bounds do not get adjusted and the TextView is aligned to the incorrect bounds. I created a custom Layout to creates the proper bounds, but maybe I'm missing something and it should be possible using the standard layout features...
EDIT: to clarify: i'm looking for a way to align the TextView with the actual image. that is with the red square in the given example.
Ok, so it's been three years and you probably figured this out long ago. But you were halfway there when you specified adjustviewBounds=true. You just needed to change the ImageView layout width and height to wrap_content at the same time.
Your TextView IS aligning to your ImageView just as you requested. If you were to give your ImageView a background color you would see that it occupies the same area as your TextView. It's just that the actual image is centered within the view as you requested.
And you can continue to use scaleType=fitCenter or centerInside depending upon what you want. Neither will crop or stretch the image and your TextView will remain aligned.
What if you use - android:scaleType="centerCrop" on the ImageView?
The image will be cropped to cover the entire layout, but the aspect ratio will be maintained.
Ok here is the problem...
I have a image background that need some text and additional graphics on it. The background image needs to be in the center of the screen and may not stretch. Here is what i need to do:
The problem is that i need to align the text to the background image.
I've tried to wrap it all into a relative layout - something like this:
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/bg_image"
android:layout_centerInParent="true"
android:src="#drawable/member_card"/>
<TextView
android:layout_height="wrap_content"
android:layout_alignLeft="#id/bg_image"
android:text="#string/membercard_info"
android:layout_marginTop="40dp"
/>
<TextView
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:layout_alignLeft="#id/bg_image"
android:layout_marginTop="200dp"
/>
</RelativeLayout>
This will not work since android adds additional padding to the image to avoid it from stretching.
Here is what happens in two different cases:
So how do I align the text to the background image?
I've solved this problem in the past in code by baking it all into one image,- but would like to do this in xml.
If you want to remove padding, you can use manually set it. However, if you want overlapping elements, you generally want to use FrameLayout. Look here: http://mobile.tutsplus.com/tutorials/android/android-sdk_frame-layout/
Set a gravity inside the frame layout to align it.
if you want an ImageView with additional layers drawn on top of that, see this thread: How to maintain multi layers of ImageViews and keep their aspect ratio based on the largest one?
There a padding around the image because you set the imageView size to fill its parent ( using match_parent )
You should try to set it to wrap its content :
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
.../>
EDIT : If your picture is bigger that the screen size, you need to have it scaled keeping the aspect ratio.
To do this, use match_parent in vertical with a scaleType to FIT_CENTER
and keep the wrap_content setting for the width ( since we want the image view left/right bounds stuck to the image content )
<ImageView
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:scaleType="fitCenter"
.../>
Is this better ?
In Android, when layout out widgets, what's the difference between fill_parent (match_parent in API Level 8 and higher) and wrap_content?
Is there any documentation where you can point to? I'm interested in understanding it very well.
Either attribute can be applied to View's (visual control) horizontal or vertical size. It's used to set a View or Layouts size based on either it's contents or the size of it's parent layout rather than explicitly specifying a dimension.
fill_parent (deprecated and renamed MATCH_PARENT in API Level 8 and higher)
Setting the layout of a widget to fill_parent will force it to expand to take up as much space as is available within the layout element it's been placed in. It's roughly equivalent of setting the dockstyle of a Windows Form Control to Fill.
Setting a top level layout or control to fill_parent will force it to take up the whole screen.
wrap_content
Setting a View's size to wrap_content will force it to expand only far enough to contain the values (or child controls) it contains. For controls -- like text boxes (TextView) or images (ImageView) -- this will wrap the text or image being shown. For layout elements it will resize the layout to fit the controls / layouts added as its children.
It's roughly the equivalent of setting a Windows Form Control's Autosize property to True.
Online Documentation
There's some details in the Android code documentation here.
fill_parent (deprecated) = match_parent
The border of the child view expands to match the border of the parent view.
wrap_content
The border of the child view wraps snugly around its own content.
Here are some images to make things more clear. The green and red are TextViews. The white is a LinearLayout showing through.
Every View (a TextView, an ImageView, a Button, etc.) needs to set the width and the height of the view. In the xml layout file, that might look like this:
android:layout_width="wrap_content"
android:layout_height="match_parent"
Besides setting the width and height to match_parent or wrap_content, you could also set them to some absolute value:
android:layout_width="100dp"
android:layout_height="200dp"
Generally that is not as good, though, because it is not as flexible for different sized devices. After you have understood wrap_content and match_parent, the next thing to learn is layout_weight.
See also
What does android:layout_weight mean?
Difference between a View's Padding and Margin
Gravity vs layout_gravity
XML for above images
Vertical LinearLayout
<?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">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="width=wrap height=wrap"
android:background="#c5e1b0"/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="width=match height=wrap"
android:background="#f6c0c0"/>
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="width=match height=match"
android:background="#c5e1b0"/>
</LinearLayout>
Horizontal LinearLayout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="WrapWrap"
android:background="#c5e1b0"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="WrapMatch"
android:background="#f6c0c0"/>
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="MatchMatch"
android:background="#c5e1b0"/>
</LinearLayout>
Note
The explanation in this answer assumes there is no margin or padding. But even if there is, the basic concept is still the same. The view border/spacing is just adjusted by the value of the margin or padding.
fill_parent will make the width or height of the element to be as
large as the parent element, in other words, the container.
wrap_content will make the width or height be as large as needed to
contain the elements within it.
Click here for ANDROID DOC Reference
fill_parent :
A component is arranged layout for the fill_parent will be mandatory to expand to fill the layout unit members, as much as possible in the space. This is consistent with the dockstyle property of the Windows control. A top set layout or control to fill_parent will force it to take up the entire screen.
wrap_content
Set up a view of the size of wrap_content will be forced to view is expanded to show all the content. The TextView and ImageView controls, for example, is set to wrap_content will display its entire internal text and image. Layout elements will change the size according to the content. Set up a view of the size of Autosize attribute wrap_content roughly equivalent to set a Windows control for True.
For details Please Check out this link : http://developer.android.com/reference/android/view/ViewGroup.LayoutParams.html