[flexcoders] Re: Defining a dynamic UI
A very similar issue is now raised in a new thread: Selecting which Child Components to add at runtime ...how to define dynamic children. --- In flexcoders@yahoogroups.com, gary_mangum [EMAIL PROTECTED] wrote: Thanks for the great responses! I see 2 great options here: - Place my array of components that might be needed into a container and change the creationPolicy to NONE. Then create
[flexcoders] Re: Defining a dynamic UI
Thanks for the great responses! I see 2 great options here: - Place my array of components that might be needed into a container and change the creationPolicy to NONE. Then create the set of components that I need once I discover which set that is using the createComponentFromDescriptor method on the container. This seems to be the option I like best. I can describe the components in the MXML once and then pick and choose which ones get created and added to the UI once I know that information. The only caveat here is that I could end up creating and destroying these components over and over as I change the set that I wish to display, however, these components are very tiny and this shouldn't be expensive. - The other option is to simply create all of the components up front and use the visible and includeInLayout properties to hide and show the appropriate set of components. This one doesn't cause me to continually create/destroy components like the previous method since I would be simply hiding/showing them. I like this one as well, but am a little partial to the previous which only creates the components that are needed. Then again, these components are tiny. I may go to this method when I get into it, who knows. Thanks again! --- In flexcoders@yahoogroups.com, iilsley [EMAIL PROTECTED] wrote: How about ( and this maybe a complete noobish way :) ) using the visible attribute .. You then also have to take into account 'layout' probably .. -- from LiveDocs --- Preventing layout of hidden controls By default, Flex lays out and reserves space for all components, including hidden components, but it does not display the hidden controls. You see blank spots where the hidden controls will appear when you make them visible. In place of the hidden controls, you see their container's background. However if the container is any of the following components, you can prevent Flex from considering the child component when it lays out the container's other children by setting the child component's includeInLayout property of the component to false: * Box, or any of its subclasses: HBox, VBox, DividedBox, HDividedBox, VdividedBox, Grid, GridItem, GridRow, ControlBar, and ApplicationControlBar, * Form * Tile and its subclass, Legend * ToolBar When a component's includeInLayout property is false, Flex does not include it in the layout calculations for other components, but still lays it out. In other words, Flex does not reserve space for the component, but still draws it. As a result, the component can appear underneath the components that follow it in the layout order. To prevent Flex from drawing the component, you must also set its visible property to false. --- In flexcoders@yahoogroups.com, Michael Labriola labriola@ wrote: To add to what Tracy was saying.. Let's say you have a component in the comps directory called MyComp. It could be in MXML or in Actionscript, it doesn't matter. First you would need to import that component definition by saying import comps.MyComp; Then, at anytime, for instance in response to a button click, you can say: var someVar:MyComp = new MyComp(); someVar.property1 = 3; someVar.property2 = 7; this.addChild( someVar ); or myViewStack.addChild( someVar ); You could make a series of functions which create these components and set them, calling the appropriate function when needed. Or you could dig a little further and learn about factories... is this basically what you were trying to do or are we missing your point? Mike --- In flexcoders@yahoogroups.com, Tracy Spratt tspratt@ wrote: You understand that if you use navigation containers, like viewStack and TabNavigator, that much of this is done for you automatically? Also, separate mxml files is a fine way to make re-useable components. Their size is not significant. Make them generic so that you can set properties and event listeners. I don't know if the mx:Component tag can be used anywhere other than in an item renderer(state?), but you might check. And you can instantiate controls at will using container.addChild(). There are also RSLs and modules. Mxml is just another way to write AS classes, use it if you like it. There are lots of options. Tracy From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of gary_mangum Sent: Tuesday, May 29, 2007 6:30 PM To: flexcoders@yahoogroups.com Subject: [flexcoders] Defining a dynamic UI Is it possible to pre-define a set of MXML components but not create them or add them to a Container in the application until a later time. In other words, I want to define some components, complete with
[flexcoders] Re: Defining a dynamic UI
--- In flexcoders@yahoogroups.com, gary_mangum [EMAIL PROTECTED] wrote: Is it possible to pre-define a set of MXML components but not create them or add them to a Container in the application until a later time. In other words, I want to define some components, complete with properties, events, etc. that will not be part of my UI until I dynamically add them as the application runs. I will decide whether or not to add them based on runtime criteria. I know that I can use states to add and remove components. If I use states, is there a way to define a component only once in MXML and then add it in 3-4 different states? I do not wish to define my component over and over inside of AddChild tags, and my components are not really specialized enough to warrant their own MXML files since there are many of them and the only real differences are their properties, events, etc. I've also thought that I could manually define my components in AS and keep them in memory until needed, but would rather define them in MXML if possible. I would also like to create the components just-in'time instead of creating them up front when they may never be needed. Anyway, thanks for any thoughts on this topic! Check out the SecureApplication class I posted on livedocs http://livedocs.adobe.com/flex/201/langref/mx/core/Application.html Basically it overrides the addChild function and adds a check to see if someone has logged in before actually running it, otherwise it queues it up with callLater until all criteria are met.
[flexcoders] Re: Defining a dynamic UI
To add to what Tracy was saying.. Let's say you have a component in the comps directory called MyComp. It could be in MXML or in Actionscript, it doesn't matter. First you would need to import that component definition by saying import comps.MyComp; Then, at anytime, for instance in response to a button click, you can say: var someVar:MyComp = new MyComp(); someVar.property1 = 3; someVar.property2 = 7; this.addChild( someVar ); or myViewStack.addChild( someVar ); You could make a series of functions which create these components and set them, calling the appropriate function when needed. Or you could dig a little further and learn about factories... is this basically what you were trying to do or are we missing your point? Mike --- In flexcoders@yahoogroups.com, Tracy Spratt [EMAIL PROTECTED] wrote: You understand that if you use navigation containers, like viewStack and TabNavigator, that much of this is done for you automatically? Also, separate mxml files is a fine way to make re-useable components. Their size is not significant. Make them generic so that you can set properties and event listeners. I don't know if the mx:Component tag can be used anywhere other than in an item renderer(state?), but you might check. And you can instantiate controls at will using container.addChild(). There are also RSLs and modules. Mxml is just another way to write AS classes, use it if you like it. There are lots of options. Tracy From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of gary_mangum Sent: Tuesday, May 29, 2007 6:30 PM To: flexcoders@yahoogroups.com Subject: [flexcoders] Defining a dynamic UI Is it possible to pre-define a set of MXML components but not create them or add them to a Container in the application until a later time. In other words, I want to define some components, complete with properties, events, etc. that will not be part of my UI until I dynamically add them as the application runs. I will decide whether or not to add them based on runtime criteria. I know that I can use states to add and remove components. If I use states, is there a way to define a component only once in MXML and then add it in 3-4 different states? I do not wish to define my component over and over inside of AddChild tags, and my components are not really specialized enough to warrant their own MXML files since there are many of them and the only real differences are their properties, events, etc. I've also thought that I could manually define my components in AS and keep them in memory until needed, but would rather define them in MXML if possible. I would also like to create the components just-in'time instead of creating them up front when they may never be needed. Anyway, thanks for any thoughts on this topic!
[flexcoders] Re: Defining a dynamic UI
How about ( and this maybe a complete noobish way :) ) using the visible attribute .. You then also have to take into account 'layout' probably .. -- from LiveDocs --- Preventing layout of hidden controls By default, Flex lays out and reserves space for all components, including hidden components, but it does not display the hidden controls. You see blank spots where the hidden controls will appear when you make them visible. In place of the hidden controls, you see their container's background. However if the container is any of the following components, you can prevent Flex from considering the child component when it lays out the container's other children by setting the child component's includeInLayout property of the component to false: * Box, or any of its subclasses: HBox, VBox, DividedBox, HDividedBox, VdividedBox, Grid, GridItem, GridRow, ControlBar, and ApplicationControlBar, * Form * Tile and its subclass, Legend * ToolBar When a component's includeInLayout property is false, Flex does not include it in the layout calculations for other components, but still lays it out. In other words, Flex does not reserve space for the component, but still draws it. As a result, the component can appear underneath the components that follow it in the layout order. To prevent Flex from drawing the component, you must also set its visible property to false. --- In flexcoders@yahoogroups.com, Michael Labriola [EMAIL PROTECTED] wrote: To add to what Tracy was saying.. Let's say you have a component in the comps directory called MyComp. It could be in MXML or in Actionscript, it doesn't matter. First you would need to import that component definition by saying import comps.MyComp; Then, at anytime, for instance in response to a button click, you can say: var someVar:MyComp = new MyComp(); someVar.property1 = 3; someVar.property2 = 7; this.addChild( someVar ); or myViewStack.addChild( someVar ); You could make a series of functions which create these components and set them, calling the appropriate function when needed. Or you could dig a little further and learn about factories... is this basically what you were trying to do or are we missing your point? Mike --- In flexcoders@yahoogroups.com, Tracy Spratt tspratt@ wrote: You understand that if you use navigation containers, like viewStack and TabNavigator, that much of this is done for you automatically? Also, separate mxml files is a fine way to make re-useable components. Their size is not significant. Make them generic so that you can set properties and event listeners. I don't know if the mx:Component tag can be used anywhere other than in an item renderer(state?), but you might check. And you can instantiate controls at will using container.addChild(). There are also RSLs and modules. Mxml is just another way to write AS classes, use it if you like it. There are lots of options. Tracy From: flexcoders@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of gary_mangum Sent: Tuesday, May 29, 2007 6:30 PM To: flexcoders@yahoogroups.com Subject: [flexcoders] Defining a dynamic UI Is it possible to pre-define a set of MXML components but not create them or add them to a Container in the application until a later time. In other words, I want to define some components, complete with properties, events, etc. that will not be part of my UI until I dynamically add them as the application runs. I will decide whether or not to add them based on runtime criteria. I know that I can use states to add and remove components. If I use states, is there a way to define a component only once in MXML and then add it in 3-4 different states? I do not wish to define my component over and over inside of AddChild tags, and my components are not really specialized enough to warrant their own MXML files since there are many of them and the only real differences are their properties, events, etc. I've also thought that I could manually define my components in AS and keep them in memory until needed, but would rather define them in MXML if possible. I would also like to create the components just-in'time instead of creating them up front when they may never be needed. Anyway, thanks for any thoughts on this topic!
[flexcoders] Re: Defining a dynamic UI
Hi, Probably you want something like this: https://www.adobe.com/livedocs/flex/2/langref/mx/core/UIComponentDescri ptor.html#UIComponentDescriptor() Let me know if this is your way Regards.
