Toggle Buttons and Event Listeners

As we mentioned earlier, when creating Flash^R apps for mobile devices, it's very important to remove event listeners as soon as they are no longer needed. In this tutorial, we will code two functions that will run when the Menu Overlay is moved on or off the stage. We will call these functions loadListeners and removeListeners.

So what will these functions do when the Menu Overlay is moved? First, let's discuss what will happen with we click the toggle button to remove the menu from the stage, which is the removeListeners() function.

For each button or hyperlink on the menu, we will want to turn everything off. For example, we will set the buttonMode and useHandCursor properties to false. Also, we don't want Flash to be listening for the button click events associated with these menu buttons when the menu is not on the stage. So we will remove the event listeners from these buttons. The example below is for the website button.

websiteBtn.buttonMode = false;
websiteBtn.useHandCursor = false;
websiteBtn.removeEventListener(MouseEvent.CLICK, goWebsite);

When the menu is toggled back onto the stage we run the loadListeners function which set the buttonMode and useHandCursor properties back to true and add event listeners to each button on the menu. For the websiteBtn we will do this.

websiteBtn.buttonMode = true;
websiteBtn.useHandCursor = true;
websiteBtn.addEventListener(MouseEvent.CLICK, goWebsite, false, 0, true);

Here is the complete code.

function removeListeners():void {

websiteBtn.buttonMode = false;
websiteBtn.useHandCursor = false;
moreAppsBtn.buttonMode = false;
moreAppsBtn.useHandCursor = false;
creditsBtn.buttonMode = false;
creditsBtn.useHandCursor = false;
indexBtn.buttonMode = false;
indexBtn.useHandCursor = false;
musicBtn.buttonMode = false;
musicBtn.useHandCursor = false;

websiteBtn.removeEventListener(MouseEvent.CLICK, goWebsite);
moreAppsBtn.removeEventListener(MouseEvent.CLICK, goMoreApps);
creditsBtn.removeEventListener(MouseEvent.CLICK, goCredits);
indexBtn.removeEventListener(MouseEvent.CLICK, goIndex);
musicBtn.removeEventListener(MouseEvent.CLICK, stopMusic);

}

function loadListeners():void {

websiteBtn.buttonMode = true;
websiteBtn.useHandCursor = true;
moreAppsBtn.buttonMode = true;
moreAppsBtn.useHandCursor = true;
creditsBtn.buttonMode = true;
creditsBtn.useHandCursor = true;
indexBtn.buttonMode = true;
indexBtn.useHandCursor = true;
musicBtn.buttonMode = true;
musicBtn.useHandCursor = true;

websiteBtn.addEventListener(MouseEvent.CLICK, goWebsite, false, 0, true);
moreAppsBtn.addEventListener(MouseEvent.CLICK, goMoreApps, false, 0, true);
creditsBtn.addEventListener(MouseEvent.CLICK, goCredits, false, 0, true);
indexBtn.addEventListener(MouseEvent.CLICK, goIndex, false, 0, true);
musicBtn.addEventListener(MouseEvent.CLICK, stopMusic, false, 0, true);

}

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	Diane Cipollo BellaOnline's Flash and Animation Editor