I am implementing a new class that extends CheckBox
In the constructor I am giving it a specific dimensions like this:
setHeight(size);
setWidth(size);
measure(size, size);
But whenever I call getHeight() or getWidth() it always gives me 0.
Am I doing something wrong?
It looks like you are trying to get your views width and height before it is initialized. This is the reason why you need to be more specific when you say whenever especially if you put your code in onCreate. If your view is visible at all try adding simple onClick and get and Log your width and height then and see what happens.
Hope this helps and enjoy your work.
Related
I'm facing a problem with the LWUIT's Textfield.
In some of my Forms I display a CategoryBar, while in others I hide it.
In some of the Forms I have Textfields, the problem presents itself when I focus on one and make the Virtual Keyboard (VKB) to appear. When the VKB appears, the screen components resize themselves to adjust to the Textfield to be visible while text is entered, but when I hide the VKB, either through the back button or the return key on the VKB, the Textfield remains with the focus, not only that, when the screen components resize themselves, the current visible Form resizes itself as if there was no CategoryBar present, so any components that are at the bottom of the Form are hidden by the CategoryBar.
This is fixed by displaying another Form (this includes PopupChoiceGroup and DatePicker) and then going back to the Form that is covered by the CategoryBar.
In other Forms where no CategoryBar is visible, sometimes the resizing when the VKB is shown causes the Forms to resize themselves as if the CategoryBar was visible, making it possible to interact with it when it shouldn't be available.
How can I make sure the focus is completely lost on the Textfield? Also, how to make sure a Form is resized correctly whether a CategoryBar is visible or not?
EDIT
I've been digging through the class reference for TextField, Form and VKB, in the later I found a method called autoAdjust which according to documentation:
Auto adjust size of the dialog. This method is triggered from a
sizeChanged event.
The method sizeChanged sounded like something I should check and in the Form's reference the description for this method is:
This method is only invoked when the underlying canvas for the form
gets a size changed event. This method will trigger a relayout of the
Form. This method will get the callback only if this Form is the
Current Form
This method seemed like the callback for resizing I was looking for, so I overrode it and placed a NotificatioBar to be displayed with the width and height values sent when the method was called.
What I found after testing this on my device was that when the Form was being resized after the VKB was shown or hidden, the height value sometimes instead of being 270 (the height for the Form when the CategoryBar is being displayed) it was sent as 320 (the full screen height, as if no CategoryBar was being displayed).
So far I haven't been able to understand why would the Form ignores the fact that the CategoryBar is being displayed or not when resizing the itself.
I tried to change the Form height inside its sizeChanged method but the Form wasn't affected by it. It seems to me what I have to modify is the canvas where the Form is being drawn, but I don't really know for sure since the canvas is hidden in LWUIT.
Could it be the canvas where my Form is being drawn is the one at fault? What is provoking this behaviour?
At the moment I found a workaround to avoid having my Components hidden by the CategoyBar because the Form resized wrongly after the VKB hid, for the scenario in which the Form resizes wrongly and displays the CategoryBar (which I don't know why is visible if I'm calling to its setVisibility method and passing false).
First I overrode the sizeChanged method:
protected void sizeChanged(int w, int h){
if(h > 270){
mainContainer.getStyle().setMargin(Component.BOTTOM, 50);
}
else{
mainContainer.getStyle().setMargin(Component.BOTTOM, 0);
}
}
I check the height value, if the value is greater than the expected height when the CategoryBar is being displayed then I set the bottom of my Container to 50, so it'll be visible.
But this wasn't enough because if I show again the same form and it resizes correctly then the Container will remain with a bottom of 50. So I overrode the onShow method too:
protected void onShow(){
int containerBottom = mainContainer.getStyle().getMargin(Component.BOTTOM);
if(this.getHeight() == 270 && containerBottom == 50){
mainContainer.getStyle().setMargin(Component.BOTTOM, 0);
}
}
I had to make sure if the height was 270 and my Container's bottom was 50 then the Container's bottom should be 0.
Since I haven't found a way to avoid having my Form to resize and show the CategoryBar when it shouldn't be displayed at all, I don't consider myself with a full answer. Will update if I find a workaround for this.
EDIT
I tried with explicitly setting the shown/hidden status by calling the setVisibility method inside the onShow method of every Form I have. So far I've been able to avoid the visual problems I experienced previously. I'm not sure if this problem was due to LWUIT or due to J2ME restrictions but this is how I worked around it.
Color newColor = new Color(197,222,90);
JButton newButton;
newButton = new JButton(icon);
newButton.setBacgroundColor(newColor);
When it is pressed it changes color. How can I keep it from changing color? I have multiple buttons, so if there is solution in one or two rows please help me, and keep in mind that I'm beginner, writing some huge classes won't help me, because I have multiple buttons with different names to be affected with this.
EDIT: Solution in one line is:
UIManager.put("Button.select", newColor);
But it changes all button colors but I need another to have different a color.
EDIT2: After some research I figured out there isn't an easy solution (but it should be). How I see it I have 2 solutions, 1. is to break buttons to separate classes and set UIManager for them, and second is to make custom buttons. It is just too much work for button.
I've found nothing that can change that particular behavior on a normal JButton. The problem being, that whatever you write in your actionlistener for the button, will occur AFTER you've let go of the mousebutton, and not "while clicking".
There are workarounds, however.
My preferred choice is, to remove all graphics from the button, and then add your own images to the button's regular and pressed states. You could take a screenshot of your GUI, cut out the button, and set that image to be both states.
JButton myButton = new JButton();
// Sets button x, y, width, height. Make the size match the image.
myButton.setBounds(5, 30, 100, 30);
// Remove border-graphics.
myButton.setBorder(null);
// Remove default graphics from the button
myButton.setContentAreaFilled(false);
// Remove the focus-indicating dotted square when focused (optional)
myButton.setFocusPainted(false);
// Here, myImage is a simple BufferedImage object.
// You can set one like this, provided you have an "images" package,
// next to your main class (ex: com.somecompany.someprogram.images),
// that contains an image:
BufferedImage myImage = ImageIO.read(getClass().getResource("images/myImage.png"));
// Then we simply apply our image to both states for the button, and we're done.
myButton.setIcon(new ImageIcon(myImage));
myButton.setPressedIcon(new ImageIcon(myImage));
Obviously there are many ways to retain and load an image, but since that's not the issue here, I'll leave additional methods out of it.
There's no need to go through it all countless times, though. It should be pretty easy to write your own custom implementation of the JButton class, in which a custom constructor takes a single parameter, being the BufferedImage, and then the constructor sets it up accordingly (changes the icons). Then all you have to do when you create a new JButton, is to use your own class, and pass it an image:
JButton btn = new MyCustomJButton(myImage);
You could also easily get along with very few images. All you need is a HashMap which holds all the images, with a String as a key. Imagine you need 4 OK-buttons. You make a single image of a button with the text "OK" written on it. Then you put that image into the HashMap, like so:
myMap.put("OK", myImage);
Then you could do this when creating a button, over and over again if you'd like more:
JButton btn = new MyCustomJButton(myMap.get("OK"));
Alternatively:
Another way of achieving this, which is pretty elaborate, but probably considered "the right way", is to use ButtonUI, as presented in this answer to another post.
If the OP is referring to the temporary change of background colour on a button with an icon at the moment the mouse is pressed, the following statement does the trick:
button.setContentAreaFilled(false);
"If you wish to have a transparent button, such as an icon only button, for example, then you should set this to false."
This took me a long time to figure out. It seems to be a little known technique, perhaps since its name gives little clue as to its effect.
With only first lane we can still see that it is clicked. You need to combine those two:
button1.setContentAreaFilled(false);
button1.setEnabled(false);
and if you don't wanna in grey color you put another button under him.
panelname.add(button1,+5,+5); \\(first not clicable, not visible button, notice +5)
panelname.add(button2,-5,-5); \(-5,-5 means it is 5 points under panel)
I am trying to change the height of my textview through code when the 4 inch screen is detected. Unfortunately I cant get my current code to work. Can anyone see what is wrong? Both ways its written it doesn't work. In the code I show both ways I've tried. I have this written in viewDidLoad method too.
If this cannot be worked out then can anyone help me out to set height attribute value in attribute inspector for both the screens (with height 568 and 480)
my code,
if ((int)[[UIScreen mainScreen] bounds].size.height==568)
{
[myTextView setFrame:CGRectMake(20.0f, 78.0f, 280.0f, 415.0f)];
}
uncheck 'use autolayout' from interface builder and use 'autosizing' from interface builder to resize your textview height
I'm having trouble creating a fluid layout with Vaadin. As I understand it, in order for a container's size to be calculated based on its contents, I have to use the setSizeUndefined() method.
This works fine, but an issue arises when I want to add components wich take up all the available space to this container with undefined size. I cannot get this to work.
Here's a simplified sample of what I'm trying to do:
VerticalLayout layout = new VerticalLayout();
layout.setSizeUndefined();
layout.setMargin(false);
layout.addComponent(createButton("A somewhat longer label"));
layout.addComponent(createButton("Short label"));
private Button createButton(String label) {
Button button = new Button(label);
button.setSizeFull();
button.setWidth("100%");
return button;
}
The buttons do not take up the entire width of the vertical layout container. I have read here and there that one is not allowed to set "100%" sizes inside containers with undefined size, but then how am I supposed to achieve what I want to achieve bearing in mind that I need that undefined size for my fluid layout?
In case someone thinks the undefined size is not necessary for my use case, I'll be happy to provide more information on that. I have a strong Flex background which may cause met to look at this problem from the wrong angle.
You are correct, you cannot use relatively sized components within a VerticalLayout that has an undefined size. The functionality you are looking for exists in an add-on called WeeLayout.
I need to show the only component on the form - HTMLComponent. Reaching the bottom of the form/component while vertical scrolling scroll bar jumps back to the top of the form. I need to prevent this.
I've tried to turn on/off scrolling on the form and HTMLComponent but anyway if there's a scroll bar - it will return to the top from the bottom. Also I've tried border and box layouts and additional container for HTMLComponent - no use.
Any ideas how to prevent such scrolling issue?
Try this (it works for me - LWUIT 1.5):
htmlComponent.getComponentForm().setCyclicFocus(false);
If you get a NullPointerException, call it after adding to the HtmlComponent to a form.
If you want to get rid of the bottom/top jump scroll, you can use
form.setCyclicFocus(false)
You should stick with border layout and place the HTML component in the center for this particular use case. You can disable form scrolling since the HTML component is indeed scrollable by default:
form.setScrollable(false);
HTMLComponent is itself scrollable
to prevent scrolling
setScrollable(false);
for horizontal scroll off
setScrollableX(false);
hope this will solve your issue
...or, you can paste this code on your Form class
public void keyPressed(int keyCode) {
int tecla = Display.getInstance().getGameAction(keyCode);
if(tecla == 8){
//if hit ENTER or principal key in mobile keyboard
}else if(tecla == 6){//down key
if(this.list_component_name.getSelectedIndex() < this.list_component_name.size() - 1)
this.list_component_name.setSelectedIndex(this.lista_bodegas.getSelectedIndex() + 1);
}else if(tecla == 1){//up key
if(this.list_component_name.getSelectedIndex() > 0)
this.list_component_name.setSelectedIndex(this.list_component_name.getSelectedIndex() - 1);
}
}
That's also work for me
form.serScrollable(false) or form.setCyclicFocus(false) didn't work for me.
I have a form and just a single HTMLComponent in it.
The problem is in HTMLComponent itself and disabling focus of the form won't affect it.
You can try with making the whole component focusable which might help in scrolling in a proper way. Along with this you should add your html component in Boderlayout.center of form and make form scrollable true and cyclic focus false.
In LWUITImplementation we have function getDragPathTime(). This javaDoc about this function:
/**
* Indicates what drag points are valid for the drag speed calculation.
* Points that are older then the current time - the path time are ignored
*
* #return the relevance time per point
*/
I also was problem especially in devices with OS S-60 Nokia. Lists was jumped from buttom to top. i solved this problem by change the return value. I change the value to 600( from 200). this occurs to fewer sampling and prevent the "jump".