Supporting multiple screens is the most important issue to provide user-friendly apps to your users. So, if you want your users to continue to use your apps, you must serve them apps that have a nice seeming screen. Consequently, you have to familiar with supporting multiple screens terms and concepts.
Terms and concepts
- Screen size
- Screen density
- Orientation
- Resolution
- Density-independent pixel (dp)
- Range of supported screens
- Small
- Normal
- Large
- Xlarge
You should learn these terms from Android developer website under “Device Capability” especially under this link “https://developer.android.com/training/multiscreen/screensizes”
How to Support Multiple Screens
- At first, you have to declare explicitly in the manifest which screen sizes your application supports
<supports-screens
android_smallScreens=”true”
android_normalScreens=”true”
android_largeScreens=”true”
android_xlargeScreens=”true”
android_anyDensity=”true” />
- You have to provide different layouts for different screen sizes
res/layout/my_layout.xml //layout for normal screen size (“default”)
res/layout-small/my_layout.xml // layout for small screen size
res/layout-large/my_layout.xml // layout for large screen size
res/layout-xlarge/my_layout.xml // layout for extra large screen size
res/layout-xlarge-land/my_layout.xml // layout for extra-large in landscape orientation
- You have to provide different bitmap drawables for different screen densities
res/drawable-mdpi/my_icon.png // bitmap for medium density
res/drawable-hdpi/my_icon.png // bitmap for high density
res/drawable-xhdpi/my_icon.png // bitmap for extra high density
- Use configuration qualifiers
- Size
- small, normal, large, xlarge
- Density
- ldpi, mdpi, hdpi, xhdpi, nodpi, tvdpi
- Orientation
- land, port
- Aspect Ratio
- Long, notlong
- Design Alternative Layouts and Drawable
Best Practices
To sum up;
- Use wrap_content, match_parent, or dp units when specifying dimensions in an XML layout file
- android:layout_width = ”wrap_content”
- android:layout_height = ”match_content”
- android:layout_width = ”100dp”
- Do not use hard coded pixel values in your application code
- Use sp for text size
- Avoid hardcoding
- Do not use AbsoluteLayout(it’s deprecated) or ConstarintLayout
- Use RelativeLayout or
- Look for layouts which are suitable for your app
- Supply alternative bitmap drawable for different screen densities
o res/drawable-mdpi/icon.png //for medium-density screenso res/drawable-hdpi/icon.png //for high-density screens
Aytunç BAKIR, Computer Engineer
Kaynak : https://developer.android.com