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In Android, a Toast is a simple UI element that can be used to give contextual feedback to a user. To display a simple Toast message, we can do the following. // Declare the parameters to use for the Toast Context context = getApplicationContext(); // in an Activity, you may also use "th...

If you don't want to use the default Toast view, you can provide your own using the setView(View) method on a Toast object. First, create the XML layout you would like to use in your Toast. <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="...

A macro can produce different outputs against different input patterns: /// The `sum` macro may be invoked in two ways: /// /// sum!(iterator) /// sum!(1234, iterator) /// macro_rules! sum { ($iter:expr) => { // This branch handles the `sum!(iterator)` case $iter.f...

In $e:expr, the expr is called the fragment specifier. It tells the parser what kind of tokens the parameter $e is expecting. Rust provides a variety of fragment specifiers to, allowing the input to be very flexible. SpecifierDescriptionExamplesidentIdentifierx, foopathQualified namestd::collection...

docker inspect supports Go Templates via the --format option. This allows for better integration in scripts, without resorting to pipes/sed/grep traditional tools. Print a container internal IP: docker inspect --format '{{ .NetworkSettings.IPAddress }}' 7786807d8084 This is useful for direct ne...

This topic specifically talks about UTF-8 and considerations for using it with a database. If you want more information about using databases in PHP then checkout this topic. Storing Data in a MySQL Database: Specify the utf8mb4 character set on all tables and text columns in your database. ...

If you need to match characters that are a part of the regular expression syntax you can mark all or part of the pattern as a regex literal. \Q marks the beginning of the regex literal. \E marks the end of the regex literal. // the following throws a PatternSyntaxException because of the un-close...

Python 2.x2.7 To import a module through a function call, use the importlib module (included in Python starting in version 2.7): import importlib random = importlib.import_module("random") The importlib.import_module() function will also import the submodule of a package directly: c...

-- Create an index for column 'name' in table 'my_table' CREATE INDEX idx_name ON my_table(name);

A unique index prevents the insertion of duplicated data in a table. NULL values can be inserted in the columns that form part of the unique index (since, by definition, a NULL value is different from any other value, including another NULL value) -- Creates a unique index for column 'name' in tabl...

To share files or to host simple websites(http and javascript) in your local network, you can use Python's builtin SimpleHTTPServer module. Python should be in your Path variable. Go to the folder where your files are and type: For python 2: $ python -m SimpleHTTPServer <portnumber> For p...

The specifier override has a special meaning in C++11 onwards, if appended at the end of function signature. This signifies that a function is Overriding the function present in base class & The Base class function is virtual There is no run time significance of this specifier as is mainl...

SQLite is a C library that is typically compiled directly into the application by downloading the source code of the latest version, and adding the sqlite3.c file to the project. Many script languages (e.g., Perl, Python, Ruby, etc.) and frameworks (e.g., Android) have support for SQLite; this is d...

Another use case for filters is to format a single value. In this example, we pass in a value and we are returned an appropriate true boolean value. function convertToBooleanValue() { return function(input) { if (typeof input !== 'undefined' && input !== null ...

Trailing spaces \s*$: This will match any (*) whitespace (\s) at the end ($) of the text Leading spaces ^\s*: This will match any (*) whitespace (\s) at the beginning (^) of the text Remarks \s is a common metacharacter for several RegExp engines, and is meant to capture whitespace characters (...

The <datalist> tag specifies a list of pre-defined options for an <input> element. It provide an "autocomplete" feature on <input> elements. Users will see a drop-down list of options as they write. <input list="Languages"> <datalist id="Langua...

In Python 2, <> is a synonym for !=; likewise, `foo` is a synonym for repr(foo). Python 2.x2.7 >>> 1 <> 2 True >>> 1 <> 1 False >>> foo = 'hello world' >>> repr(foo) "'hello world'" >>> `foo` "'hello world'"...

This example starts Notepad, waits for it to be closed, then gets its exit code. #include <Windows.h> int main() { STARTUPINFOW si = { 0 }; si.cb = sizeof(si); PROCESS_INFORMATION pi = { 0 }; // Create the child process BOOL success = CreateProcessW( L"C:...

Available in Django 1.9+ from django.contrib.postgres.fields import JSONField from django.db import models class IceCream(models.Model): metadata = JSONField() You can add the normal **options if you wish. ! Note that you must put 'django.contrib.postgres' in INSTALLED_APPS in your s...

Pass data in native Python form, for example list, dict, str, None, bool, etc. IceCream.objects.create(metadata={ 'date': '1/1/2016', 'ordered by': 'Jon Skeet', 'buyer': { 'favorite flavor': 'vanilla', 'known for': ['his rep on SO', 'writing a book'] }, ...