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Under res folder, create a new folder called "anim" to store your animation resources and put this on that folder. shakeanimation.xml <?xml version="1.0" encoding="utf-8"?> <rotate xmlns:android="http://schemas.android.com/apk/res/android" and...

public static Unsafe getUnsafe() { try { Field unsafe = Unsafe.class.getDeclaredField("theUnsafe"); unsafe.setAccessible(true); return (Unsafe) unsafe.get(null); } catch (IllegalAccessException e) { // Handle } catch (IllegalArgumentExcept...

public class UnsafeLoader { public static Unsafe loadUnsafe() { return Unsafe.getUnsafe(); } } While this example will compile, it is likely to fail at runtime unless the Unsafe class was loaded with the primary classloader. To ensure that happens the JVM should be loaded with...

MySQL3.19 DROP TABLE IF EXISTS MyTable; PostgreSQL8.x DROP TABLE IF EXISTS MyTable; SQL Server2005 If Exists(Select * From Information_Schema.Tables Where Table_Schema = 'dbo' And Table_Name = 'MyTable') Drop Table dbo.MyTable SQLite3.0 DROP TABLE IF EXI...

Sometimes, programmers who are new Java will use primitive types and wrappers interchangeably. This can lead to problems. Consider this example: public class MyRecord { public int a, b; public Integer c, d; } ... MyRecord record = new MyRecord(); record.a = 1; // OK ...

When you do a groupby you can select either a single column or a list of columns: In [11]: df = pd.DataFrame([[1, 1, 2], [1, 2, 3], [2, 3, 4]], columns=["A", "B", "C"]) In [12]: df Out[12]: A B C 0 1 1 2 1 1 2 3 2 2 3 4 In [13]: g = df.groupby(...

Example Using Activity w/ LocationRequest /* * This example is useful if you only want to receive updates in this * activity only, and have no use for location anywhere else. */ public class LocationActivity extends AppCompatActivity implements GoogleApiClient.ConnectionCallbacks, ...

Data Model public class Item { private String name; public String getName() { return name; } public void setName(String name){ this.name = name; } } Layout XML <?xml version="1.0" encoding="utf-8"?> <layout xmlns:an...

SELECT s.name + '.' + t.NAME AS TableName, SUM(a.used_pages)*8 AS 'TableSizeKB' --a page in SQL Server is 8kb FROM sys.tables t JOIN sys.schemas s on t.schema_id = s.schema_id LEFT JOIN sys.indexes i ON t.OBJECT_ID = i.object_id LEFT JOIN sys.partitions p ON i.object_id = ...

Caller info attributes can be used to pass down information about the invoker to the invoked method. The declaration looks like this: using System.Runtime.CompilerServices; public void LogException(Exception ex, [CallerMemberName]string callerMemberName = "", ...

Optional Parameters In TypeScript, every parameter is assumed to be required by the function. You can add a ? at the end of a parameter name to set it as optional. For example, the lastName parameter of this function is optional: function buildName(firstName: string, lastName?: string) { // ...

You can customize your theme’s color palette. Using framework APIs 5.0 <style name="AppTheme" parent="Theme.Material"> <item name="android:colorPrimary">@color/primary</item> <item name="android:colorPrimaryDark">@color/pri...

XML elements often nest, have data in attributes and/or as character data. The way to capture this data is by using ,attr and ,chardata respectively for those cases. var doc = ` <parent> <child1 attr1="attribute one"/> <child2>and some cdata</child2> </p...

Operators such as +, -, ?? are a kind of function named using symbols rather than letters. They are invoked differently from functions: Prefix: -x Infix: x + y Postfix: x++ You can read more about basic operators and advanced operators in The Swift Programming Language.

init Called synchronously after the instance has been initialized and prior to any initial data observation. created Called synchronously after the instance is created. This occurs prior to $el setup, but after data observation, computed properties, watch/event callbacks, and methods ha...

import "reflect" value := reflect.ValueOf(4) // Interface returns an interface{}-typed value, which can be type-asserted value.Interface().(int) // 4 // Type gets the reflect.Type, which contains runtime type information about // this value value.Type().Name() // int value.SetInt(5)...

import "reflect" // this is effectively a pointer dereference x := 5 ptr := reflect.ValueOf(&x) ptr.Type().Name() // *int ptr.Type().Kind() // reflect.Ptr ptr.Interface() // [pointer to x] ptr.Set(4) // panic value := ptr.Elem() // this is a deref value.Type().Name() // int...

In go it can sometimes be useful to know which underlying type you have been passed. This can be done with a type switch. This assumes we have two structs: type Rembrandt struct{} func (r Rembrandt) Paint() {} type Picasso struct{} func (r Picasso) Paint() {} That implement the Painter ...

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Introduction Classes that implement this interface no longer support __sleep() and __wakeup(). The method serialize is called whenever an instance needs to be serialized. This does not invoke __destruct() or has any other side effect unless programmed inside the method. When the data is unseriali...