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And here as you can see it says azing tasks should be ideally be used for short operations.



2

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OK so a few seconds at the most.



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OK.



4

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So this is going to be actually this glass is used for short operations.



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And as you can see here it's just a few seconds at the most.



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So if you have for example tasks such as downloading an image from the internet or such tasks in your



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application you can use this class azing task.



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But if you need to keep Fretz running for long periods of time for example you have a very heavy task



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and you can.



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And you need to actually.



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And it may take actually a lot of time.



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OK.



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It is highly recommended you use the various API is provided by the job that uty that can cart that



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concurrent package such as executor.



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Can are concurrent package such as the executer Fred Poole executed and future task.



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So these are classes actually inside this Java that you that can current package.



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I'll talk more about these classes later but for now we want to actually use this asynchronous async



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task class and it's just that an asynchronous task is defined by computation that runs on a background



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front and whose result is published under you like.



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OK so let me try to read this line again.



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An asynchronous task is defined by your computer nation that runs on a background Fred and whose result



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is published on the UI for it an asynchronous task is defined by free generic types called pro-ams progress



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resolved.



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OK so let's try to go back to what Android studio here as you can see inside these angle brackets.



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First of all I need to actually specify Dipodomys comma and the second level we need to specify the



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progress.



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OK comma and the first of all we need to specify the result.



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OK the result that I want to actually get from the Internet for example the Possum's is going to be



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the Padam meters.



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Ok the input that we actually put inside is async task is in the background.



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OK.



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So our input is going to be for example.



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And you are well.



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So as you can see here I have this you are well and I want to actually download this image from the



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internet and I actually chose this image here.



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So as you can see here I actually selected this of you image here and as you can see this is going to



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be the image.



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And here is do all.



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So the water is going to be off type strange putty.



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So the perimeter as you can see here is going to be type strange.



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So here I can just type in strange OK the data type is going to be of type string the data type of the



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input that you want to actually put inside the async task is going to be of types to change.



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And this is going to be that you are this you are is going to be inside to double quotes.



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So this is going to be of type strange that you want to actually put as a pedometer for this async task.



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So the second parimutuel as you can see here is progress.



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So this progress paramita it is going to show us how much of the contents have been actually downloaded



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from the Internet.



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We can actually see what what percentage of the contents have been downloaded from the Internet and



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then actually put that value somewhere in order to show to the user that what is going to be.



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How much time is going to take for example to download this image this particular image from the Internet.



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So that's the job of this pedometer.



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And in the Android documentation as you can see here we have these descriptions here async tasks are



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generic types.



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And as you can see and it says patta progress the type of the Procrustes units published the type of



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the Procrustes is published during the background computation.



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OK.



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So and as you can see here we have this result that type of the result of the background can computation.



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So as you can see here because we want to actually download this image from the Internet.



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So if you want to actually get an image from the Internet.



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Right.



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So that image is going to be offtake bitmap.



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OK this is going to be the output the outputs that I want to get from these async task class is going



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to be of type bitmap so that progress is going to be what.



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I don't want to actually get disvalue.



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OK.



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Get these units published of the day for example and the image is downloaded from the internet.



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I just want to put this Voyt value here.



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I don't want to get any value here as a progress and the result is going to be offtake bitmap the bitmap



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is actually the output.



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So this thrain is the input that I want to put inside these async task and repeat map is the output



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right.



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So now I need to actually open and close this class using these curly braces but this opening curly



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brace and these are closing calibrates.



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So now we need to actually implement free methods here.



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The first one is Vendi when the image is actually is going to download from the Internet.



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OK.



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Actually before downloading an image from the Internet is going to be dismembered on poorly executed



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Meffert.



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So this is going to be executed before downloading an image from the Internet.



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OK.



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The second effect is actually when the image is being downloaded from the Internet.



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So that task is going to be in the background right.



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So the name of this Meffert is going to be do in background as you can see here and here as you can



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see the return type as of this Mufti's bitmap because here as you can see I specified that the output



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type is going to be of type bitmap.



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So I just select this Meffert here.



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And as you can see here this is that Meffert to in background.



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And the first method is going to be vente the image is actually downloaded from the Internet.



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And the task of downloading is finished and then I want to put that image on the image for you and the



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user interface as you can see here.



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So that if it is going to be on post executes.



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So these are the free important methods of this async task class.



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OK.



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So now inside this download image task class as you can see this is actually an inner class that is



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inside of this main activity class.



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So you can access these at user interface components variables or these methods that are inside the



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outer class.



98

00:06:35,810 --> 00:06:36,270

OK.



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So inside this download image task class I want to actually first of all declare two objects the first



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one is actually of type progress they like.



101

00:06:45,500 --> 00:06:51,770

OK so you want to actually show it to the user a dialogue in order to let them know that the application



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is actually downloading an image from the Internet.



103

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And the name of this object is progress like semicolon.



104

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OK.



105

00:06:59,090 --> 00:07:04,350

And the second object that I want to actually declare here is of type context.



106

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And the name of this context is context.



107

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And then I need to put a semicolon at the end of my statement and then here I need to actually specify



108

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a constructor for this download image task class.



109

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So here I can just type in public and the name of the constructor must be the same as the name as the



110

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name of this download image task class.



111

00:07:27,200 --> 00:07:31,390

So here I can just type in download image task OK.



112

00:07:31,460 --> 00:07:36,590

And then I need to put a pair of practices here and then I need to open and close this constructed by



113

00:07:36,590 --> 00:07:38,410

using these curly braces.



114

00:07:38,480 --> 00:07:45,790

And here I want to specify that these are constructed actually accepts an argument of type context.



115

00:07:45,980 --> 00:07:49,160

OK so the name of this argument is going to be context.



116

00:07:49,160 --> 00:07:49,760

OK.



117

00:07:50,070 --> 00:07:56,630

And inside these are constructor you want to initialize these two objects that are actually declared



118

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inside the standard image task class.



119

00:07:59,090 --> 00:08:04,550

So the first one is progress Stalock assignment operator.



120

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And here I can just typing new progress dialog.



121

00:08:11,000 --> 00:08:17,360

And for the context as you can see here I can pass this context here and then put a semicolon at the



122

00:08:17,360 --> 00:08:19,290

end of my statement.



123

00:08:19,310 --> 00:08:25,040

And here are before initializing this progress Stalock I need to actually initialize this context object



124

00:08:25,490 --> 00:08:29,840

because I am actually passing this context as a path emitter to this.



125

00:08:29,840 --> 00:08:32,320

A constructed of this progress Daler class.



126

00:08:32,330 --> 00:08:36,510

So here again I'll refer to the name of this context assignment operator.



127

00:08:36,680 --> 00:08:42,400

So here as you can see I made this mistake when I actually referred to the name of this context here



128

00:08:42,400 --> 00:08:47,870

it is that it is actually fairly in to this context as a Padam here because as you can see the name



129

00:08:47,870 --> 00:08:54,610

of this instance variable here as you can see is actually the same as the name of this argument.



130

00:08:54,620 --> 00:08:59,840

So when I actually inside this when I'm in say this a constructor and of a and I refer to the name of



131

00:08:59,840 --> 00:09:02,330

this context it's going to actually refer to the.



132

00:09:02,340 --> 00:09:04,730

To this construct to this context as a pattern.



133

00:09:04,730 --> 00:09:05,350

OK.



134

00:09:05,630 --> 00:09:09,670

So here I need to put this these here these that context.



135

00:09:09,680 --> 00:09:16,410

So it is now referring to this context here inside this class download image task assignment operator.



136

00:09:16,430 --> 00:09:20,020

So now you want to refer to the name of this context here as a padded me.



137

00:09:20,060 --> 00:09:20,600

OK.



138

00:09:20,900 --> 00:09:27,710

So now I am actually initializing this context that I actually get from this pattern meter is argument



139

00:09:28,100 --> 00:09:34,250

here I am initializing the context here as you can see here this context context as you can see here



140

00:09:34,280 --> 00:09:40,130

I am assigning this context that I get as a perimeter to this context here as you can see inside this



141

00:09:40,130 --> 00:09:41,550

download image task.



142

00:09:41,990 --> 00:09:49,340

So now that I can initialised my two objects now inside this on pre-text acute MFA Meffert when actually



143

00:09:49,340 --> 00:09:50,940

put in some lines of code here.



144

00:09:50,960 --> 00:09:57,440

So when the user actually wants to download the image from the internet why by clicking on the spot



145

00:09:57,440 --> 00:10:03,930

in here I want to show them a message dialogue in order to let them know that an image is being downloaded



146

00:10:03,960 --> 00:10:05,900

from the internet so they should wait.



147

00:10:05,970 --> 00:10:06,580

OK.



148

00:10:06,840 --> 00:10:12,690

So in order to do that as you can see I have this progress dialog uptick here so I can just refer to



149

00:10:12,690 --> 00:10:19,770

the name of this object Proclus dialogue that sit message as you can see I mean it is an acute Meffert.



150

00:10:19,770 --> 00:10:20,240

OK.



151

00:10:20,320 --> 00:10:26,750

So this is going to be executed just before I actually click on the button download button and then



152

00:10:26,810 --> 00:10:29,500

it can actually download the image from the Internet.



153

00:10:29,610 --> 00:10:32,130

So this is the NPE execute method right.



154

00:10:32,250 --> 00:10:35,320

Set message and inserted prentices.



155

00:10:35,400 --> 00:10:38,700

I put the two double quotes on here I can just put the message.



156

00:10:38,790 --> 00:10:45,490

For example downloading image.



157

00:10:45,680 --> 00:10:46,320

Please visit



158

00:10:49,640 --> 00:10:49,960

OK.