Develop Reference

Use setRequiredPasswordComplexity(passwordComplexity : Int) in API less than 31

I want to set password policy on screen lock and now I use setPasswordQuality(ComponentName admin, int quality) in DevicePolicyManager but this method is deprecated on API 31 and they add new method(setRequiredPasswordComplexity(passwordComplexity : Int)).
I can use this method in API < 31?
If I can,how should I use it?
https://developer.android.com/reference/android/app/admin/DevicePolicyManager#setRequiredPasswordComplexity(int)

As the documentation already states the method was added in API 31 and since there is no backward compatibility library for this so this functionality can only be used on devices with api 31 or above

I think your problem might solve here. You can check the build version by
if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.S){
// Do something for version 31 and above versions
} else{
// do something for phones running an SDK before 31
}

Android version check

I'm not new to Android and I'm well used to the version handling and how to condition it, but when I see this it troubles me...
// Check if we're running on Android 5.0 or higher
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
// Call some material design APIs here
} else {
// Implement this feature without material design
}
On any device pre lollipop this line would crash the app because the Build.VERSION_CODES.LOLLIPOP field does not exists... so why is this in the recommended solution in the documentation?
I'm really wondering what am I missing?

Well in that case use this
// Check if we're running on Android 5.0 or higher
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
// Call some material design APIs here
} else {
// Implement this feature without material design
}
Build.VERSION_CODES.LOLLIPOP = 21

Well, you must compile your project with the latest SDK version. Your constants are replaced with corresponding integer values during compilation. No matter what version of Android you run the application on - integers are the same

Try this one
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP_MR1) {
// Marshmallow+
}else{
//below Marshmallow
}
Note: Build.VERSION_CODES.LOLLIPOP_MR1==22
Build.VERSION_CODES.M==23

Bit a late to answer, but, today I encountered with the same issue on Android Studio 3.4.1
So the workaround is:
Upgrade to the latest Android SDK.
And,
After Marshmallow/Android 6 Build.VERSION_CODES.xxx full names are replaced with initials and some other variations.
So, now for Marshmallow, it will be:
Build.VERSION_CODES.M
And for Nougat:
Build.VERSION_CODES.N
And so on.
Read more about the build version codes here: Android Developer Reference

Check Android build project target API level at runtime [duplicate]

This question already has answers here:
Programmatically obtain the Android API level of a device?
(7 answers)
Closed 8 years ago.
I have an application, and it behaves differently when I run it on API 18 or 19. This is not a problem, and I know why does it happen.
However, I want to write one code that will deal with both the versions.
Is there any way to get in runtime which API my application was built with? Specifically, I would like to get 18 or 19 if I build my application with these APIs.
EDIT
It seems to be a duplicate question. I thought that the BUILD_VERSION is something else, because, when I compiled both the versions to API 18 and 19, and print the version, I receive 18. It looks like another problem (although I specified API 19, it is compiled according to 18).
I found that the problem was in the emulator configurations.

I didn't understand your problem completely. But if you want to check which Build Version your app is working on and then act accordingly the you can use the following.
if(Build.VERSION.SDK_INT == 18 ){
// Do some stuff
}
else if (Build.VERSION.SDK_INT == 19) {
// Do some stuff
}
else{
// Do some stuff
}

The Android docs provides some sample code of how to load bitmaps effectively that handles this problem.
The code defines static methods in a class Utils that it references when it needs to know what platform the app is running on. The benefit of doing this is that you can reuse the function calls rather than rewriting long conditional statements over and over. The code looks like this:
public static boolean hasFroyo() {
// Can use static final constants like FROYO, declared in later versions
// of the OS since they are inlined at compile time. This is guaranteed behavior.
return Build.VERSION.SDK_INT >= Build.VERSION_CODES.FROYO;
}
public static boolean hasGingerbread() {
return Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD;
}
public static boolean hasHoneycomb() {
return Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB;
}
public static boolean hasHoneycombMR1() {
return Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR1;
}
public static boolean hasJellyBean() {
return Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN;
}
public static boolean hasKitKat() {
return Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
}

android.os.Build.VERSION.SDK_INT

Check this link out
Build Version Codes
So you can use as follows...
int thisDevicesApi =Build.VERSION.SDK_INT;
if (thisDevicesApi <=Build.VERSION_CODES.GINGERBREAD) {
//for example
//do something
}

android setLayerType crashing on lower version

I used the setLayerType method in my app to check the device hardwareAccelerated true or false, it's working on higher version (i.e 3+) but in lower version the app is crashing.
Here is my code snippet:
try {
if (android.os.Build.VERSION.SDK_INT > android.os.Build.VERSION_CODES.GINGERBREAD) {
view.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
}
} catch(Exception ex) {
}
I tried to check on AndroidManifest.xml but that doesn't work for me.

Api level check you have set is wrong. Change to
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.HONEYCOMB) {
view.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
}

The setLayerType() works only on Api 11 and above. And GINGERBREAD is Api 9 and GINGERBREAD_MR1 is Api 10.

How to only execute code on certain API level

For instance, this code:
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.GINGERBREAD) {
myCalendarView.setOnDateChangeListener(
new OnDateChangeListener() {
#Override
public void onSelectedDayChange(CalendarView view, int year, int month, int dayOfMonth) {
Toast.makeText
(
getApplicationContext(), ""+dayOfMonth, 0
).show();
}
}
);
}
Gives error:
Description Resource Path Location Type Call requires API level 11
(current min is 8):
android.widget.CalendarView#setOnDateChangeListener example.java /example/src/com/example/example line
20 Android Lint Problem
I understand why I get this error compile-time. But is there any way to mark a source Java class to only be used on certain API level-11? Or surround code blocks with a define/similar so the code is late-bound/jitted only on devices above API level-11? What is the best solution to achieve what I want? (Which is to provide an activity with CalendarView on devices capabile of it.)

I'm not sure if this is going to solve your issue,
but what you are using to check version is not working under API 9
(and you are supporting since API 8).
You should use:
if (Build.VERSION.SDK_INT > 9) {
Or as problematic function is API 11, check for "SDK_INT>10"
Then for lint errors on eclipse, do as people comment, disable lint errors or add the #SuppressLint("NewAPi") or the target to that function to 11.

For anyone stumbling upon this much later, conditionally executing code based on the API version at runtime is currently a valid way of supporting different platform versions.
See: https://developer.android.com/training/basics/supporting-devices/platforms#version-codes
Where it says:
Android provides a unique code for each platform version in the Build
constants class. Use these codes within your app to build conditions
that ensure the code that depends on higher API levels is executed
only when those APIs are available on the system.
And gives examples:-
Java:
private void setUpActionBar() {
// Make sure we're running on Honeycomb or higher to use ActionBar APIs
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
Kotlin:
private fun setUpActionBar() {
// Make sure we're running on Honeycomb or higher to use ActionBar APIs
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
actionBar.setDisplayHomeAsUpEnabled(true)
}
}