I still can't understand how images are scaled. I have this 600px x 600px image. I scaled it to different sizes (ie. to 450 x 450, 300x300 and 225x225). I did that in order for devices with different screen densities adjust the size of the image. Then I placed an imageview to a generic 1280x800 10.1" tablet, which is mdpi as stated by the ADT. It views properly on the 10.1 tablet graphical layout but seems oversized on the other devices especially on the phone category. Here is the link to image:
The layout width and height are also set to wrap_content, should I set it to a value in dp?
since, its an mdpi tablet, the resource is being picked from the drawable-mdpi folder and thus appearing that small.
Perhaps you can create a layout-mdpi-xlarge folder and then in that layout refer a copy of the image from the xhdpi folder.
Related
I'm making an android App that shows images at full screen.
I learned some about dpi and dp, but I didn't find how many pixel must be the largest side of my images (in prospective to good fit also in landscape mode) to appear good in different devices.
As in the documentation, the most used screen configurations are normal with hdpi, xhdpi and xxhdpi density:
So, if my thinking is correct, I can make only one image to fit the xxhdpi to works fine also with the other two densities, and put it in Android Studio under the "res/drawable" folder (without qualifier).
Specifying the image size in dp in the layout, Android should scale the image for the smaller configurations.
But, for the xxhdpi, how many pixel must be the largest side of my image, in pixel, to show good?
Edit: how many pixel must be the longest side of my image to be showed properly in a device with xxhdpi density without the image appearing grainy?
All images are photo, not icons, so I can't use the vector graphics.
By looking at the Android Documentation. One can estimate the size of the picture. look at below picture
So, your image resolution should be in similar resolution
LDPI: 200 X 320px
MDPI: 320 X 480px
HDPI: 480 X 800px
XHDPI: 720 X 1280px
XXHDPI: 960 X 1600px
XXXHDPI: 1440 x 2560px
A little bit of +/- won't affect the outcome because with these standard sizes the aspect ratio of any portrait picture should be respected.
Well, if you put the image which fits the xxxhdpi inside the folder drawable, then it will fit all the screens.
But there is another way to use only one image instead of using multiple images for different resolutions. It's by using svg images which are vector images that will not be affected by zoom in or zoom out.
To use svg you need to follow these instructions:
Make the icon to be icon.svg
In the Android Studio, right click on drawable folder
Choose New -> Vector Asset
Choose Local File (SVG, PSD)
Choose your svg file
Click Next and choose the name
Click Finish
In the app build.gradle add the following inside android block:
vectorDrawables {
useSupportLibrary true
}
In the xml layout file, add the following:
<AppCompatImageView
android:width="wrap_content"
android:height="wrap_content"
app:srcCompat="#drawable/your_svg_file"
/>
Android have ratios defined for a image to set in all different drawables
Android icons require five separate sizes for different screen pixel densities. Icons for lower resolution are created automatically from the baseline.
mdpi: 160 dpi 1×
hdpi: 240 dpi 1.5×
xhdpi: 320 dpi 2×
xxhdpi: 480 dpi 3×
xxxhdpi:640 dpi 4×
Above size is for normal pixel icons. There are fix android size for Action bar, Dialog & Tab icons, Launcher icons & Notification icons
Check this link for more details http://iconhandbook.co.uk/reference/chart/android/
You have to take a look at the current market of smartphones.
Here you can see the screen sizes and resolutions of the most popular devices in the market.
http://screensiz.es/
Order the list in pixel per inch and you will see that top smartphones have resolutions bigger than 500 ppi or another way to see it, much bigger than 72ppi of your images.
If you have enough space to store or mechanism to download images try to test with full quality. If thats too much try to find a compromise. Lower image quality and see the result in high resolution screen.
Note that you didn't posted here the total size of image, in case is bigger than screen size, take a look at total size of image and compress it to fit your needs, maintaining as much as possible the resolution.
Edit: Looking only to size of image in pixels, the current biggest screen in smartphone is 2560 x 1440 pixels, so you wont need any image bigger than this.
If I understand your answer correctly, you are talking about images (pictures of lovely cats and dogs?) and not about icons?
I prefer putting images into the nodpi folder.
nodpi Resources for all densities. These are density-independent
resources. The system does not scale resources tagged with this
qualifier, regardless of the current screen's density.
Afterwards I would create a fullscreen ImageView and let imageView do the scaling if needed
I am having trouble managing my application layouts in three different resolutions; 720x1280, 1080x1920 and 1440x2560.
In drawable-xhdpi folder is the corresponding images to 720x1280 resolution.
The folder drawable-xxhdpi is the corresponding images to 1080x1920 resolution and in drawable-xxxhdpi to 1440x2560.
I began to adjust the screens in layout folders. The layout-sw360dp was setting screens for 720x1280 and the layout-sw480dp the 1080x1920.
When testing in the emulator 720x1280 all settings worked perfectly.
But to test the emulator 1080x1920, oddly taking this information in layout-sw360dp folder and not the layout-sw480dp.
In the case of adjusting each folder layout-sw360dp and layout-sw480dp, I'm using margin with values in 'dp' and emulator higher values (layout-sw480dp) are being dropped are being used and the values of the layout-sw360dp.
How can I manage three screen sizes correctly?
Well designed Android applications cater for varying screen sizes, the screen size being a function of both resolution and density. Using several layout-sw###dp folders allows you to vary the layout according to the width of the display, e.g. showing fewer elements and controls on a small screen and perhaps more detail on a large one.
The 'sw' in the layout folder name is the 'shortest width' a display must have in device independent pixels (dip). One dip = 1 real pixel on a 160 density screen. So on a 320 density screen, 2 real pixels make up one dip.
Your nexus 5 has 480/160 = 3 real pixels per dip. So with a width resolution of 1080, that is 360dip wide.
Your nexus 4 has 320/160 = 2 real pixels per dip. So with a width resolution of 768, that is 384dip wide.
Neither device is more than 480 dip wide so both use the sw360dp folder.
Both devices are physically very similar in size. The Nexus 5 (5.4inch screen) has more pixels than the Nexus 4 (4.7inch screen) but the pixels are physically smaller. So it is correct that the same layout is used for both. The UI should look the same on both devices, assuming you correctly specify the size and layout of your various UI elements in dip.
As a further example, I have an old tablet (10inch screen) with a resolution of 800x1280 and a low density of 149, hence is 859dip wide. You can comfortably display far more info on a screen that size than on a Nexus 4/5, hence you might consider creating a layout-sw720dp for that.
So you appear to be doing exactly the right thing already by designing different layouts for different screen sizes. Just remember that resolution is not the same thing as screen size. Screen size is a combination of resolution and density.
As for your drawables, you are also already doing the right thing by using drawable-xhdpi, drawable-xxhdpi etc with appropriate resolution images in each one. So for example a small device with an extremely high density would likely use the 1440x2560 images and the sw360dp layout. My low res tablet would use the 720x1280 images, unless you'd put something in drawable-mdpi which is where it would look first.
So firstly you'd create appropriate resolution images in the drawable folders so that they would look as good as possible on different resolution screens. Then create appropriate swxxxdp for your layouts so they take up the appropriate space depending on the physical screen size, i.e. make good use of available screen space on large devices and don't clutter up small ones. It's likely you would want to go further and create -land and -port versions of each as well.
It is worth noting that even if you only have one layout folder and one drawable folder, your application will still work on all devices. Android simply looks for the best choice and if there is only one, it'll use that. Adding in the various folders simply allows you to make your app look as good as possible on a range of devices.
Everything I have discussed here and more is explained in detail at http://developer.android.com/guide/practices/screens_support.html.
Dear All I’m going to work in android application I should design the interface. I read articles on http://developer.android.com/design/index.html but I still have some missing point.
Do I need to design back ground for each device size ?
Check for this Link for supporting multiple screen. This link will show you how to create the different layout for different screen size devices.
But even if you want to make a Unique layout for supporting multiple screen in orientation or portrait mode then,
For image, use 9 patch images.
Here is the link http://developer.android.com/tools/help/draw9patch.html
For width and height of any widgets, use wrap_content or match_parent or you can use android:layout_weight and android:weightSum
Avoid using the pixels i.e. px
Use dp
By this you can create the unique layout working for multiple screens, but that screen should be in orientation or portrait mode.
If you want to support for for both,then you have to createlayout-landfor landscape mode in the res folder.
Actually, you should. There are 4 main screen sizes in android those get layout xmls from res/layout-xlarge, res/layout-large, res/layout-normal and res/layout-small. At the same time, you should use different image resolutions for different screens those get images from drawable-hdpi, drawable-xhdpi, drawable-mdpi and drawable-ldpi.
It depends on the background type. If your background is an image with high resolution you should provide different images for different screen sizes if the whole background is an image.
You can also:
Make background from tiles (like icloud.com)
Specify a ninepatch image if your image is something like a frame where corners should remain the same and the body should be scaled (not very good if you have some picture)
Specify multiple different images for different screen resolutions and densities. To do so read supporting multiple screens. If you need even more precision in image scaling and quality you can use the fundamental size of screen attribute which is sw<N>dp - you can specify the smallest width of the screen where your image should be used. This is a qualifier name for a resource folder.
Some values you might use here for common screen sizes:
320, for devices with screen configurations such as:
240x320 ldpi (QVGA handset)
320x480 mdpi (handset)
480x800 hdpi (high density handset)
480, for screens such as 480x800 mdpi (tablet/handset).
600, for screens such as 600x1024 mdpi (7" tablet).
720, for screens such as 720x1280 mdpi (10" tablet).
You should also have a look at other qualifiers that make Android choosing image at runtime (screen density, Available width, Available height, Screen size or Screen aspect). By combining these qualifiers and testing carefully you will be sure that the user has the best experience on each device.
I'm trying to develop for an android tab with the resolution of 1280x720. But when I place an image, say 1000x500, into the xml view it appears almost two times smaller. When I change its height and width from wrap_content to 1000px and 500px, it looks ok in xml, but when I launch it in the emulator, it gets very blurry, as if it would be at first scaled down and then expanded again.
Any ideas?
Thanks!
Put the drawables for tablet in the drawable-xlarge folder and the problem may dissapear.
Maybe your problems is that the most tablets have xlarge screens and mdpi screen density and you put the drawables in the hdpi folder.
For more info see this page.
Try using "dp" instead of pixels. Also place the drawable in the density specific folder. between ldpi and hdpi the size in pixels need to be twice for them to show up as of same size on the device. For example a launcher icon on ldpi device is 36 x 36px while on hdpi it is 72 x 72 px
Use same ratio to create your image in higher resolution with larger size.
I use .png as a background for a custom button that I declare in XML like this
android:background="#drawable/samplepng"
But I can't get the resolution right for tablet screens :
For example, my ressource is a 200x200 pixels .png (initially designed for iOS and retina)
I place a 100x100 px version in the drawable-mdpi folder and a 200x200 px version in the drawable-xhdpi folder.
I also need to have a layout for a typical 320x480 screen in the layout folder and another layout for 10" tablets in the layout-xlarge folder.
The size of the button is 100x100 dp in the normal layout and 200x200 dp for xlarge layout, so that it looks right.
With the Android emulator, a 10" tablet uses mdpi ressources and xlarge layout.
As a result, the button background is drawn with a scaled version of the 100x100 image which looks very blurry, as opposed to the crisp 200x200 original image.
If I don't use a mdpi ressource, it looks blurry just as well.
Am I doing something wrong ? is it only an emulator problem and it looks nice on a real device ?
Please help, I read 10 times google's doc but can't find an answer.
If you don't launch the emulator with 'Scale display to real size' checked, then it will always use mdpi drawables.
See here for more.
Your issue might be in the android version your targeting. Try switching the emulator to android 3.0 and 3.1.