Scrolling through list element causes text elements to scroll as well - apache-flex

I'm using a list element with variableRowHeight and word-wrap set to true like in the example below:
http://blog.flexexamples.com/2007/10/27/creating-multi-line-list-rows-with-variable-row-heights/
When I scroll through the list with a mouse scrollwheel the text in the listItems also scroll. I know that this is to do with the height of the textField... but I am unsure how to best resolve this issue. Any thoughts are appreciated!
The issue that I am experiencing also occurs in the example above.

OK, solved it after a bit of work. Thought I would put it here for others:
This can be simply solved by extending the List element, and the ListItemRenderer and modifying a couple of lines:
First up, extend the List element:
package au.com.keeghan.controls {
import mx.controls.List;
import mx.core.ClassFactory;
public class ExtendedList extends List{
public function ExtendedList(){
super();
itemRenderer = new ClassFactory(ExtendedListItemRenderer);
}
}
}
Now we want to extend the newly created item renderer (ExtendedListItemRenderer). Because there isn't actually that much code required, we can just put it in the same .as file. We do this by declaring it as a internal class, and locating it outside of the package above... just below the closing bracket:
import mx.controls.listClasses.ListItemRenderer;
internal class AsOneListItemRenderer extends ListItemRenderer{
override protected function measure():void{
super.measure();
var w:Number = 0;
if (icon)
w = icon.measuredWidth;
// Guarantee that label width isn't zero
// because it messes up ability to measure.
if (label.width < 4 || label.height < 4)
{
label.width = 4;
label.height = 16;
}
if (isNaN(explicitWidth))
{
w += label.getExplicitOrMeasuredWidth();
measuredWidth = w;
measuredHeight = label.getExplicitOrMeasuredHeight();
}
else
{
measuredWidth = explicitWidth;
label.setActualSize(Math.max(explicitWidth - w, 4), label.measuredHeight + 3);
label.validateNow();
label.height = label.textHeight + 5;
measuredHeight = label.getExplicitOrMeasuredHeight() + 3;
if (icon && icon.measuredHeight > measuredHeight){
measuredHeight = icon.measuredHeight;
}
}
}
}
Now, the majority of the above code is actually just copied from the ListItemRenderer, the magic occurs down the bottom... specifically these lines:
label.setActualSize(Math.max(explicitWidth - w, 4), label.measuredHeight + 3);
label.validateNow();
label.height = label.textHeight + 5;
measuredHeight = label.getExplicitOrMeasuredHeight() + 3;
All I do here is add some height to both the label, and the overall measuredHeight which in the end is the thing that is causing this issue.
The only downside to this solution is that you will get a larger amount of padding below the listItem element, however you can still make this look good by playing around with the verticalAlign and padding css properties.

Related

Removing background image from label in tornadofx

I have two css classes on a tornadofx label bound to a SimpleBooleanProperty. One which has a background image and a blue border and one which has no background image and a yellow border.
Snippet from View containing label:
val switch: SimpleBooleanProperty = SimpleBooleanProperty(false)
label("my label"){
toggleClass(UIAppStyle.style1, switch.not())
toggleClass(UIAppStyle.style2, switch)
}
Snippet from UIAppStyle:
s(style1){
textFill = Color.YELLOW
maxWidth = infinity
maxHeight = infinity
alignment = Pos.CENTER
backgroundImage += this::class.java.classLoader.getResource("img.png")!!.toURI()
backgroundPosition += BackgroundPosition.CENTER
backgroundRepeat += Pair(BackgroundRepeat.NO_REPEAT, BackgroundRepeat.NO_REPEAT)
borderColor += box(Color.BLUE)
}
s(style2){
textFill = Color.YELLOW
maxWidth = infinity
maxHeight = infinity
alignment = Pos.CENTER
borderColor += box(Color.YELLOW)
}
When switch = false, there is a background image and a blue border. When switch = true, there is the same background image and a yellow border. I'm not finding out how to get the background image to remove. Interestingly enough, if I add a different background image to style2, it changes correctly.
Edit: To remove two toggleClasses and introduce new strange problem:
class MyView : View(){
...
init{
...
row{
repeat(myviewmodel.numSwitches){
val switch = myviewmodel.switches[it]
val notSwitch = switch.not()
label("my label"){
addClass(UIAppStyle.style2)
toggleClass(UIAppStyle.style1, notSwitch)
}
}
}
}
This code snippet does not work for me. However, if I add private var throwsArray = mutableListOf<ObservableValue<Boolean>>() as a field of MyView and add notSwitch to the array, then the same exact code works. It's almost as if notSwitch is going out of scope and becoming invalidated unless I add it to a local array in the class?
I don’t understand why you want to have two different toggleClass for the same control. As you pointed out, the problem in your case is that when the backgroundImage is set, you need to set a new one in order to change it. But in your case, you only have to add the style without backgroundImage first and them set toggleClass with the style with backgroundImage. Like this:
label("my label"){
addClass(UIAppStyle.style2)
toggleClass(UIAppStyle.style1, switch)
}
button {
action {
switch.value = !switch.value;
}
}
Edit: This ilustrate what I'm talking about in comments:
class Example : View("Example") {
override val root = vbox {
val switch = SimpleBooleanProperty(false)
val notSwitch = switch.not()
label("my label"){
addClass(UIAppStyle.style2)
toggleClass(UIAppStyle.style1, notSwitch)
}
button("One") {
action {
switch.value = !switch.value;
}
}
button("Two") {
action {
notSwitch.get()
}
}
}
}
You can put the notSwitch.get() in any action and without trigger that action it does the work. Check how I put it in the action of button Two, but without clicking that button even once, it works.
This is actually some kind of hack, in order to achieve what you want. But I don’t see the reason why my initial solution with true as default value for property shouldn’t work.
Edited to do inverse of status
Here is simple example of a working toggle class using your styling:
class TestView : View() {
override val root = vbox {
val status = SimpleBooleanProperty(false)
label("This is a label") {
addClass(UIAppStyle.base_cell)
val notStatus = SimpleBooleanProperty(!status.value)
status.onChange { notStatus.value = !it } // More consistent than a not() binding for some reason
toggleClass(UIAppStyle.smiling_cell, notStatus)
}
button("Toggle").action { status.value = !status.value }
}
init {
importStylesheet<UIAppStyle>()
}
}
As you can see, the base class is added as the default, while styling with the image is in the toggle class (no not() binding). Like mentioned in other comments, the toggleClass is picky, additive in nature, and quiet in failure so it can sometimes be confusing.
FYI I got to this only by going through your github code and I can say with confidence that the not() binding is what screwed you in regards to the toggleClass behaviour. Everything else causing an error is related to other problems with the code. Feel free to ask in the comments or post another question.

TreeView scrolling jumps when using large graphic nodes (TornadoFX/JavaFX)

In the following TornadoFX/Kotlin code
import javafx.scene.control.TreeItem
import javafx.scene.control.TreeView
import tornadofx.*
class MyObj {
var type : Int = 0
constructor(type : Int) {
this.type = type
}
}
class MainView: View("Minimal TV demo") {
var treeRoot : TreeItem<MyObj> = TreeItem()
var objectsTreeView : TreeView<MyObj>? = null
override val root = vbox {
objectsTreeView = treeview(treeRoot) {
showRootProperty().value = false
cellFormat {
if(it.type == 0) {
text = "Test"
graphic = null
}
else {
text = null
graphic = vbox {
label("Label 1")
button("123")
textarea {
prefWidth = 100.0
prefHeight = 125.0
}
}
}
}
}
}
init {
with (root) {
for(i in 1..10) {
val x = TreeItem(MyObj(0))
treeRoot.children.add(x)
x.children.add(TreeItem(MyObj(1)))
}
}
}
}
when opening a few of the tree items and scrolling the tree view, the tree view contents and slider seems to act rather "jumpy", i.e. when I move the slider down, the mouse moves but the slider and content stay where it is, until the mouse gets so far down, then the content jumps. It just doesn't feel or look good.
I believe I could get around this by adding separate TreeItem's for each UI element row, but is there a way to achieve a smooth scroll without doing this? I tried suing a fixed cell height, which seems to work, but of course this doesn't look right at all given that some rows a shorter than others.
Don't use cellFormat for complex tree UIs, since the elements will be recreated very rapidly and most probably cause flicker. Your best bet is to create a subclass of TreeCellFragment and configured it using the cellFragment call.
Now you can create the UI only once per Tree cell, and reuse it when the data it represents changes. This is much more performant.

dynamic add component

I want to dynamically add component in Container like Canvas(TileList constraints each child has the same size, GridList is poor in performance), for example
<mx:Canvas id="myHolder" width="600" height="550">
</mx:Canvas>
<mx:Button label="Add Button" click="addButton()"/>
when I click the button, I hope add a component(whatever the component is, and maybe each component has different size), and if the total width of all added child is greater than myHolder, I hope the new child can begin in new line, and stretch the height of myHolder at the same time.(layout with custom code is better)
On Canvas you have complete freedom to lay components anywhere using their x and y properties, so there's a lot of ways to skin this cat. Since you need rows, one of the methods may be (not tested):
//inside of your Canvas-based component
private function updateChildrenPositions():void
{
var rowY:Number = 0;
var rowWidth:Number = 0;
var rowHeight:Number = 0;
for (var i:int = 0, total:int = numChildren; i < total; i++)
{
var child:DisplayObject = getChildAt(i);
if (rowWidth + child.width > width)
{
//child will cause overflow, start next row
rowY += rowHeight;
rowWidth = 0;
rowHeight = 0;
}
rowWidth += child.width;
child.x = rowWidth;
child.y = rowY;
if (child.height > rowHeight) rowHeight = child.height; //accumulating max height
}
height = rowY + rowHeight;
}
This assumes Canvas has fixed width and set height depending on layout. You can add paddings and gaps later, it's a good exercise :)
To get the functionality you want, I wouldn't use an HBox. As alxx suggested, a TileList would be a better fit in this situation.
Here are some examples using a TileList to get you started:
http://blog.flexexamples.com/category/halo/tilelist/
http://learn.adobe.com/wiki/display/Flex/TileList

Is there a multiline text workaround for Flex

Is there a workaround for displaying multiline text in Flex 3? The two controls I have tried so far are mx:Text, and mx:TextArea. Each control has its own bug associated with it. For reference: mx:Text bug - http://bugs.adobe.com/jira/browse/SDK-9819 mx:TextArea bug - http://bugs.adobe.com/jira/browse/SDK-12616. Basically, neither control handles scrolling correctly if you do not specify a height and the text wraps onto the next line (height is determined dynamically by Flex, based on the wrapping). Does anybody have a workaround that might be helpful?
Thanks.
Update: One of the methods I have tried in the past has been to manually calculate the height of a mx:Text element. I can do this by using the following:
var textItem:Text = new Text();
var len:int = value.length;
var lines:int = int(len/115) + 1;
var height:int = lines * 20;
textItem.height = height;
While this seems to get around the problem in mx:Text, there is one big fault. The calculation relies heavily on font-size, letter-spacing, and the width of textItem. I can use this method, and move on with my project. However, maintenance on this is inevitable, and with code like this, it will a gigantic PITA.
I've had to deal with this a few times myself. The best way I've found to get dynamic height sizing of <mx:Text> is to leave the height out of the text and then specify a percent height of 100% on the enclosing VBox, HBox, etc. Something like the following should work for you:
<mx:VBox width="100%" height="100%">
<mx:Text text="Your really long text goes here." width="100%"/>
</mx:VBox>
As this is a bit of a hack itself, your milage may vary.
Edit
If you want to extend your above example so that maintenance on the code is easier, you should look into the TextLineMetrics class. This will allow you to measure the width and height of your text, taking into account font, size, etc. The docs for TextLineMetrics can be found here. To use your above example, you'd want to do something like the following:
var textItem:Text = new Text();
var metrics:TextLineMetrics = textItem.measureText( value );
var len:int = metrics.width;
var lines:int = int(len/textItem.width) + 1;
var height:int = lines * metrics.height;
textItem.height = height;
I use a variable height text area class that works very well for me:
package
{
import mx.controls.TextArea;
/**
* TextArea that xpands to the height of the content contained
* within.
* #author joel
*
*/
public class VariableHeightTextArea extends TextArea
{
public function VariableHeightTextArea()
{
super();
}
override protected function updateDisplayList(unscaledWidth:Number, unscaledHeight:Number) : void
{
super.updateDisplayList(unscaledWidth, unscaledHeight);
if(this.height != int(this.textField.measuredHeight) + 5 )
{
this.height = this.textField.measuredHeight + 5;
}
}
}
}

Styling UITextField

I've been playing around with different methods of determining at runtime the width of a "label" so that I can resize the "label" because I don't want it to truncate. I've finally found an easy solution through UITextField which allows me to set the .autoSize which is great! However, now I'm trying to "style" (simply adjust font and font size) of the UITextField but it seems that I have to do it manually with '.htmlText' (which I'll gladly accept if that is the ONLY way).
I'm using the .text to set the value of the label.
My test case involves a HBox (I'm actually using a Grid but they should be the same and I've done testing on both):
I style the HBox and the style carries through to the UITextField. I don't believe this will work for me because I have other components inside that I need to style differently.
I've tried: UITextFormat and TextFormat (I see that the .htmlText being updated accordingly but the output doesn't update. Then I noticed that whenever I called hbox.addChild(myUITextField) it would override the .htmlText
I've tried setting the style with myUITextField.setStyle("fontSize", 20) before and/or after the call to addChild neither of which made an impact on the display as per what I noted above.
Changes are being made but they seem to be overrided when I add it to the display.
So what do I need to do in order to style the UITextField aside from manually setting it along with my contents in .htmlText? Solutions not using UITextField is fine as long as there is some easy way of not truncating the text.
EDIT: I want to just do textField.setStyle('fontSize', 20) and expect that every time I change the text, I wouldn't need to use HTML to go with it (so I can just do textField.text = 'something else' and expect that it will still have a font size of 20). This is what I meant by not using .htmlText (sorry if I wasn't clear before).
2nd EDIT: I guess I should present the whole issue and maybe that'll clarify what I did wrong or couldn't achieve.
My intent is to have a Grid and add text into it. I do not want it to wrap or scroll so I add it to the next row in the Grid when the current row's children total width exceeds some number. In order to add it to the next row, I need to be able to calculate the width of the text. I would like to be able to style that text individually based on cases and there might be other components (like a TextInput). Essentially what I'm trying to accomplish is "Fill in the Blank".
I've included code to show what I'm currently doing and it works somewhat. It might be un-related to the original issue of styling but I can't figure out how to adjust the distance between each UITextField but aside from that this fits what I would like to accomplish. Relevant to the question is: I would like to change the way I style each UITextField (currently setting .htmlText) into something a bit straightforward though like I previously mentioned I'll gladly accept using .htmlText if that's the only solution.
So I have a Grid with x Rows in it and in each row, I have exactly one GridItem. Based on the input, I add UITextField and TextInput into the GridItem going on to the next GridItem when necessary. If you have a better way of doing so then that would be better but I guess what I really want is to find a different way of styling.
Also another problem, I'm not sure of the exact way to add a TextField into the display. I tried:
var t : TextField = new TextField();
t.text = "I'm a TextField";
hBox.addChild(t); // doesn't work
//this.addChild(t); // doesn't work either
But I get the following error:
TypeError: Error #1034: Type Coercion failed: cannot convert flash.text::TextField#172c8f9 to mx.core.IUIComponent.
Here's what I have that's working.
private function styleQuestionString(str : String) : String {
return '<FONT leading="1" face="verdana" size="20">' + str + '</FONT>';
}
private function loadQuestion(str : String) : void {
/* Split the string */
var tmp : Array = str.split("_");
/* Track the current width of the GridItem */
var curWidth : int = 0;
/* Display components that we will add */
var txtField : UITextField = null;
var txtInput : TextInput = null;
/* Track the current GridItem */
var curGridItem : GridItem = null;
/* Track the GridItem we can use */
var gridItemAC : ArrayCollection = new ArrayCollection();
var i : int = 0;
/* Grab the first GridItem from each GridRow of Grid */
var tmpChildArray : Array = questionGrid.getChildren();
for (i = 0; i < tmpChildArray.length; i++) {
gridItemAC.addItem((tmpChildArray[i] as GridRow).getChildAt(0));
}
curGridItem = gridItemAC[0];
gridItemAC.removeItemAt(0);
/* Used to set the tab index of the TextInput */
var txtInputCounter : int = 1;
var txtFieldFormat : UITextFormat = new UITextFormat(this.systemManager);
txtFieldFormat.leading = "1";
//var txtFieldFormat : TextFormat = new TextFormat();
//txtFieldFormat.size = 20;
/* Proper Order
txtField = new UITextField();
txtField.text = tmp[curItem];
txtField.autoSize = TextFieldAutoSize.LEFT;
txtField.setTextFormat(txtFieldFormat);
*/
var txtLineMetrics : TextLineMetrics = null;
var tmpArray : Array = null;
curGridItem.setStyle("leading", "1");
var displayObj : DisplayObject = null;
for (var curItem : int= 0; curItem < tmp.length; curItem++) {
/* Using UITextField because it can be auto-sized! */
/** CORRECT BLOCK (ver 1)
txtField = new UITextField();
txtField.text = tmp[curItem];
txtField.autoSize = TextFieldAutoSize.LEFT;
txtField.setTextFormat(txtFieldFormat);
***/
tmpArray = (tmp[curItem] as String).split(" ");
for (i = 0; i < tmpArray.length; i++) {
if (tmpArray[i] as String != "") {
txtField = new UITextField();
txtField.htmlText = styleQuestionString(tmpArray[i] as String);
//txtField.setTextFormat(txtFieldFormat); // No impact on output
txtLineMetrics = curGridItem.measureHTMLText(txtField.htmlText);
curWidth += txtLineMetrics.width + 2;
if (curWidth >= 670) {
curGridItem = gridItemAC[0];
curGridItem.setStyle("leading", "1");
if (gridItemAC.length != 1) {
gridItemAC.removeItemAt(0);
}
// TODO Configure the proper gap distance
curWidth = txtLineMetrics.width + 2;
}
displayObj = curGridItem.addChild(txtField);
}
}
//txtField.setColor(0xFF0000); // WORKS
if (curItem != tmp.length - 1) {
txtInput = new TextInput();
txtInput.tabIndex = txtInputCounter;
txtInput.setStyle("fontSize", 12);
txtInputCounter++;
txtInput.setStyle("textAlign", "center");
txtInput.width = TEXT_INPUT_WIDTH;
curWidth += TEXT_INPUT_WIDTH;
if (curWidth >= 670) {
curGridItem = gridItemAC[0];
if (gridItemAC.length != 1) {
gridItemAC.removeItemAt(0);
}
// TODO Decide if we need to add a buffer
curWidth = TEXT_INPUT_WIDTH + 2;
}
curGridItem.addChild(txtInput);
txtInputAC.addItem(txtInput);
/* Adds event listener so that we can perform dragging into the TextInput */
txtInput.addEventListener(DragEvent.DRAG_ENTER, dragEnterHandler);
txtInput.addEventListener(DragEvent.DRAG_DROP, dragDropHandler);
txtInput.addEventListener(DragEvent.DRAG_EXIT, dragExitHandler);
}
/* Add event so that this label can be dragged */
//txtField.addEventListener(MouseEvent.MOUSE_MOVE, dragThisLabel(event, txtField.text));
}
}
After about 8 hours of searching for a solution to what would seem to be such a simple issue I FINALLY stumbled on your posts here... Thankyou!!!
I have been stumbling around trying to get TextField to work and had no Joy, Label was fine, but limited formatting, and I need to be able to use embedded fonts and rotate. After reading the above this finally worked for me:
var myFormat:TextFormat = new TextFormat();
myFormat.align = "center";
myFormat.font = "myFont";
myFormat.size = 14;
myFormat.color = 0xFFFFFF;
var newTxt:UITextField = new UITextField();
newTxt.text = "HELLO";
addChild(newTxt);
newTxt.validateNow();
newTxt.setTextFormat(myFormat);
The order of addChild before the final 2 steps was critical! (myFont is an embedded font I am using).
One again... a thousand thankyou's...
John
EDIT BASED ON THE ASKERS FEEDBACK:
I didn't realize you wanted to just apply one style to the whole textfield, I thought you wanted to style individual parts. This is even simpler for you, won't give you any trouble at all :)
var textFormat: TextFormat = new TextFormat("Arial", 12, 0xFF0000);
myText.setTextFormat(textFormat);
Be aware that this sets the style to the text that is in the TextField, not necessarily future text you put in. So have your text in the field before you call setTextFormat, and set it again every time you change it just to be sure it stays.
It's probably best if you use a normal TextField as opposed to the component. If you still want the component you may need to call textArea.validateNow() to get it to update with the new style (not 100% sure on that one though) Adobe components are notoriously bad, and should be avoided. :(
To see all available options on the TextFormat object see here
END EDIT ---------
This is easy enough to just do with CSS in a normal old TextField.
var myCSS: String = "Have some CSS here, probably from a loaded file";
var myHTML: String = "Have your HTML text here, and have it use the CSS styles";
// assuming your textfield's name is myText
var styleSheet: StyleSheet = new StyleSheet();
styleSheet.parseCSS(myCSS);
myText.autoSize = TextFieldAutoSize.LEFT;
myText.styleSheet = styleSheet;
myText.htmlText = myHTML;
Supported HTML tags can be found here
Supported CSS can be found here
The reason you have a problem adding Textfield to containers is that it doesn't implement the IUIComponent interface. You need to use UITextField if you want to add it. However, that's presenting me with my own styling issues that brought me to this question.
A few things I know:
TextField is styled using the TextFormat definition, and applying it to the textfield. As Bryan said, order matters.
setStyle does nothing on IUITextField, and the TextFormat method doesn't seem to work the same as in normal TextFields. (Edit #2: Ahah. You need to override the "validateNow" function on UITextFields to use the setTextFormat function)
To autosize a TextArea, you need to do something like this (inheriting from TextArea):
import mx.core.mx_internal;
use namespace mx_internal;
...
super.mx_internal::getTextField().autoSize = TextFieldAutoSize.LEFT;
this.height = super.mx_internal::getTextField().height;
Found this code on, I think, on StackOverflow a while back. Apologies to the original author. But the idea is that you need to access the "mx_internal" raw textfield.
Text and TextArea have wrapping options. (Label does not). So if you set the explicit width of a Text object, you might be able to size using the measuredHeight option and avoid truncation.
(edit: That was #4, but stackoverflow parsed it into a 1...)

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