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Hello and welcome.

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In this lecture we are going to add the code to make the music player work.

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All right.

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First thing I want to do a sum generate an event handler for each of these buttons.

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Basically an event handler is used to response to an event an event basically something an action that

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is performed on an application.

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When the application is running for example a click is an event.

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So the correspondent corresponding event handler would be a click event handler.

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So let's start with the brass button.

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So double click on that.

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And that would generate a stop of the code is top meaning it just generates an empty method or empty

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function.

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So we have to write the code in between these curly braces.

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You can see them the cursor is flashing waiting for us to start writing the code.

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What I am going to do here I'm going to use an if statement just to check or to check the dialog box

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to see if the file has been open.

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When you click on the browse button so would type in if we just to the intelligence skip not the guide.

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So in the if statement we added an open file dialog box so I'm gonna pass that into the if statement.

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So it's a lowercase o.

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So this is the look.

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This will now become the ope.

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This is the open file a box we added earlier on to our form.

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So we'll need to do here.

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We need to attach a method to it that will use to display the box the open dialogue.

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So if you press dot or period it gives you a list of methods you can use if you type in show.

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It would show you this show dialog box.

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So this show dialog is a method every method must be enclosed in parentheses.

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So it tells you this this is a sure dialog box.

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So what we need to do is complaining at the moment because I've not finished writing the code.

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So what I need to do I need to set a need to way for the if statement to check something.

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So to check or evaluate you do double equals two.

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And I wanted to check the dialog there.

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So this is dialogue results.

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And I want to attach a value to it and you can attach and poke.

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So if you're not sure what any parts of the code does just place your mouse over it and the idea will

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illustrate or tell you give you a tool tip guide us to what that code does it tells you this is a method

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a wrongs a common dialog box with a default owner.

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OK.

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That tells you that that is an open file open file dialog for form one form one is the is the form that

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this dialogue is attached to and the.

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Okay here the dialog box returns value is okay.

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Okay tells you usually sent from a button labeled okay.

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Okay in this instance is the button is not a hook not code okay by gives you a guide.

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What that what is this method does not is I've got this red squiggly line here because it's complaining

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that I have not finished the code telling me that this is an invalid expression.

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So it's telling me you know it's expecting because if the code is finished I should put a semicolon

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there but it's not finished.

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Is an if statement when you are using the if statement you get to you have to specify the code that

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will run for that if statement.

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So to do that I need to specify blank curly braces just expand that in between the curly braces is where

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I will write the code that will be activated in response to this if statement.

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So what I'm going to do I'm going to reference the text box.

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We added a text box earlier whether the text box 1.

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So dot text I'm going to attach a text property to it.

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All right.

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And I'm gonna set that value to equals to the open dialogue.

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I'm going to set it to equals to that and I'm going to attach a file name to that.

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All right.

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So if you put your mouse over there to tell you what that does is say it gets all sets the string containing

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the file names selected in the file dialog box if you put your mouse over that tells you what that does

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tells you what that does.

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Okay.

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So if you're not sure and just put your mouse over there and give you two tip guide the next thing you

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want to do when you are using a music player you need to specify a path where the files will be picked

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up from.

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So I'm going to reference r music player.

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Remember we declared it.

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We called it.

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I changed the name to this.

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So you put your mouse over it I tells you that's the music player.

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So I'm going to references and you need to specify a U.R.L. path that is a part for where the music

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files is coming from.

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So I'm going to set that to equals to the text box.

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So that means it will get the location of the music and displayed in the text box area.

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Okay.

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Is gonna displayed as a text that's basically what that is saying.

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So that's the code done for this button.

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I just save that and go back in to our designer and click on the play button.

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It would generate a blank again generated as top of the event handler.

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So in between this curly braces I need to specify the code because this is a play it's going to want

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when the button is clicked it will just play the music.

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This is quite easy to do.

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So again I reference the music player which is this fair ball here.

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And how attach a control v just to you can do the control.

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So there's a control called this just double click on it and then I'll attach a method to it a play

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method.

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So these are various metals you can attach to one on one for this is just the play method.

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So that's a play method and yes to a semicolon and that's it.

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So this single line of code is responsible for playing the music.

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So I'll save that go back into a designer and do the same for the pause.

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This is the event handler for the polls.

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I'm gonna save time.

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Just copy

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paste it here and just change the method to post

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code that's a lowercase

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OK.

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Go back to the control.

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Save that.

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Go back.

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Double click on the stop button generates a stop of the event handler paste same thing

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and just type in a stop notice as a stop method.

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That's all I need to do for that.

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Come here and grab the exit.

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This is different.

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I don't need to call the player.

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All I need to do is attach a close.

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There's a method called Close.

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So I want when the exit button is clicked it will close the application.

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So our code is basically finished.

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So click save and let's test the application.

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So to test we start debugging.

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We click on Start and just wait for it to load.

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All right.

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It has loaded so click on the browser.

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It should give us a dialog box.

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Excellent.

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So we need to go to music.

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You can click any music files by the way.

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I'm just gonna click on the default music sample music that Microsoft provided with the operating system.

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I just try the first one.

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I'm not sure if you can hear that this plane okay.

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That's a play you can see the path is this plane the.

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I can click on Pulse play then click on stop and then exit.

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Excellent.

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So we have successfully created a music player.

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Thank you so much for your time.

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Take care.

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Bye for now.