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Drawing an image from a data URL to a canvas
...
in javascript , using jquery for canvas id selection :
var Canvas2 = $("#canvas2")[0];
var Context2 = Canvas2.getContext("2d");
var image = new Image();
image.src = "images/eye.jpg";
Context2.drawImage(image, 0, 0);
html5:
<canv...
Discard all and get clean copy of latest revision?
...ndlines for all of my tools, so I tend to do it using the UI:
1. First, select "commit"
2. Then, display ignored files. If you have uncommitted changes, hide them.
3. Now, select all of them and click "Delete Unversioned".
Done. It's a procedure that is far easier to remember than comman...
How do I use WebStorm for Chrome Extension Development?
...ript > Libraries
Click Download
Make sure TypeScript community stubs is selected
Select chrome from the list (you can find it quickly by just typing chrome)
Click Download and Install
Click OK to close the Settings dialog.
Steps 2-6 illustrated below:
In Subsequent Projects
In any subse...
Blocks and yields in Ruby
...y:
days = ["monday", "tuesday", "wednesday", "thursday", "friday"]
# select those which start with 't'
days.select do | item |
item.match /^t/
end
=> ["tuesday", "thursday"]
Or, we can also provide a custom sort algorithm, for instance based on the string size:
days.sort do |x,...
Can't delete virtual device from Eclipse, android
...e inside [Your Device].avd folder
From Android Studio
Open AVD Manager
Select virtual device that you want to delete
Click down arrow at the end and select [Show on Disk] it will open directory
Find *.lock files and delete inside [Your Device].avd folder
After these steps it will allow you to ...
Convert data.frame column format from character to factor
...yr::mutate_if() to convert all character columns or dplyr::mutate_at() for select named character columns to factors:
library(dplyr)
# all character columns to factor:
df <- mutate_if(df, is.character, as.factor)
# select character columns 'char1', 'char2', etc. to factor:
df <- mutate_at(d...
How do I design a class in Python?
...on could help you create one just as easily. Maybe you could stay: Query().select('Country').from_table('User').where('Country == "Brazil"'). It doesn't matter exactly the syntax -- that is your job! -- the key is the object is helping you hide something, in this case the data necessary to store and...
How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...t have to have a placeholder for it in the Insert statement. Then a simple select * into the target table auto populated this column. Here are the two SQL statements that I used on PostgreSQL 9.6.4.
ALTER TABLE target ADD COLUMN some_column SERIAL;
INSERT INTO target SELECT * from source;
...
Can I have multiple primary keys in a single table?
...hese practices, but there is nothing in the relational model that requires selecting a primary key among the candidate keys.
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What to do on TransactionTooLargeException
...and application?
Using intents to share huge data, (for example, the user selects huge number of files from gallery share press share, the URIs of the selected files will be transferred using intents)
receiving bitmap files from service
waiting for android to respond back with huge data (for exampl...