constant
Java:
class StaticDemoActivity {
public static final String LOAN_TYPE = "loanType";
public static final String LOAN_TITLE = "loanTitle";
}
Kotlin:
class StaticDemoActivity {
companion object {
val LOAN_TYPE = "loanType"
val LOAN_TITLE = "loanTitle"
}
}
//perhaps
class StaticDemoActivity {
companion object StaticParams{
val LOAN_TYPE = "loanType"
val LOAN_TITLE = "loanTitle"
}
}
//perhaps
class StaticDemoActivity {
companion object {
const val LOAN_TYPE = "loanType"
const val LOAN_TITLE = "loanTitle"
}
}
Note: The const keyword is used to modify constants, and can only modify val, not var. The name of companion object can be omitted and can be referred to by Companion.
Reference constants (references here are only for java references to kotlin code)
The TestEntity class references constants in StaticDemoActivity
class TestEntity {
public TestEntity () {
String title = StaticDemoActivity.Companion.getLOAN_TITLE();
}
}
//perhaps
class TestEntity {
public TestEntity () {
String title = StaticDemoActivity.StaticParams.getLOAN_TITLE();
}
}
//perhaps
class TestEntity {
public TestEntity () {
String title = StaticDemoActivity.LOAN_TITLE;
String type= StaticDemoActivity.LOAN_TYPE;
}
}
Static method
Java code:
class StaticDemoActivity {
public static void test(){
,,,
}
}
Kotlin:
class StaticDemoActivity {
companion object {
fun test(){
,,,
}
}
}
//perhaps
class StaticDemoActivity {
companion object StaticParams{
fun test() {
,,,
}
}
}
Reference to static methods (references here are only for java reference to kotlin code)
The TestEntity class references static methods in StaticDemoActivity
class TestEntity {
public TestEntity () {
StaticDemoActivity.Companion.test();
}
}
//perhaps
class TestEntity {
public TestEntity () {
StaticDemoActivity.StaticParams.test();
}
}
The companion object {} modifies static constants, or static methods, singletons, etc.