i want to use following symbols for buttons in my app:
arrows http://img402.imageshack.us/img402/3176/arrowso.jpg
here my code:
Button goToFirstButton = new Button("\uE318");
Button prevPageButton = new Button("\uE312");
Button nextPageButton = new Button("\uE313");
Button goToLastButton = new Button("\uE319");
and the result is
result http://img693.imageshack.us/img693/9063/resultbu.jpg
It seems, that \uE318 and \uE313 are wrong. What should i use instead? For goToLastButton and goToFirstButton i prefer to use this images
alt text http://img3.imageshack.us/img3/5724/singlearrow.jpg
but i can't find, which code should i use.
I would suggest to use Icons on Buttons instead of special characters, because the ability
to display may be strongly affected by availability of fonts on client workstation.
The unicode codepoints you want to use are part of a private use area, i.e. every font manufacturer is free to put whatever character they like at whatever position. The font you used to look up the arrow characters is simply a different font than the one used for displaying the button text. If the button text maps \uE318 and \uE313 to some Chinese (?) graphem, then that's not wrong, just different.
Although multiple people have made the argument you should avoid using these codepoints because you can't rely on the users' systems having a font which displays these characters, the reason you're getting the wrong characters in your example case has been entirely missed. All of the symbols you are trying to draw are in the "private use area" which means that the symbols involved will potentially be different in every single font.
The Unicode standard states:
Private Use Area (E000-F8FF)
* The Private Use Area does not contain any character assignments, consequently no character code charts or namelists are provided for this area.
If you embed the particular font you want to use to insure you can use these codepoints, that's fine. But that does mean you should, indeed, use the \u#### notation in your code, because embedding the characters as Unicode directly means the source won't make sense unless somebody views it in the correct font.
All in all, it's probably better to use icons unless you already have a symbol font you think is simply far superior to any graphical work you would otherwise do.
◀ ▶
There are a couple of symbols close to what you want in the Geometric Shapes chart. However, as others have said, use icons and stay out of the private use area.
Java source files are UTF-8 encoded, so you can put the symbols you want directly in the source code (just copy 'n paste from a font viewer or web), as long as you use a decent editor. No need to use this confusing "\uXXXX" notation. For instance, I've found this useful for Greek letters commonly used in scientific notation (δ, ρ, ψ...) - you can even use them as variable names.
Of course, your font of choice must have the symbols you want, otherwise it won't work.
I would suggest that if you are worried about the client font's ability to display a particular character, use the following:
private static final HashMap<Character, Font> fontCache = new HashMap<Character, Font>();
public static Font getFontThatCanDisplay(char c, int style, float size) {
Font f = fontCache.get(c);
if (f == null) {
f = UIManager.getFont("Label.font");
for (Font font: GraphicsEnvironment.getLocalGraphicsEnvironment().getAllFonts()) {
if (font.canDisplay(c)) {
f = font;
break;
}
}
fontCache.put(c, f);
}
return f.deriveFont(style, size);
}
I also suggest using icons. Not all fonts have symbols for all unicode character points.
You may get it working by specifying a particular font. But what if that font is found on Windows 7 computers, but not on Mac OS X or Linux or Windows XP? Then the system will choose another font, based on the browser defaults, and that default might not have the symbols you want.
I will defend using Unicode glyphs on buttons, but it's really easy to implement the Icon interface and use paintIcon() to draw anything you want. The tutorial "Creating a Custom Icon Implementation" is a good example; this code shows a more complex, animated histogram.
Related
I am having a Whatsapp chat txt file inside of which emojis have been replaced by such text------> "���"
I want to convert that text to specifics emojis. How can I do that and use it inside a java application?
As #Abhishek pointed out, you need to use a different type of encoding. Whatsapp does backup with UTF-8 converting the emoticons into string representations. If you want to see the real emoji, you will have to use Unicode instead. Unicode contains sections which specify emoji as "characters". They're regular characters, you only need a font which can display them. Also see the Unicode Emoji FAQ.
In a text file, characters are basically encoded as numbers in the form of bytes. To display those visually on a computer screen you need a font which contains the visual glyph to render this character. Since the process is always numeric identifier → font → visible glyph, it should be pretty obvious that a "character" can be anything visual, including emoji or any other image.
Maybe all you need is a a font which contains the visual glyph to render these characters. See this for reference.
I am working a java chat application and I am adding emoticons by replacing the emoticon shortcut, like :) ,with ◕‿◕ . Its not an image that I am replacing it with but simple text. Now the problem that I am facing is that sometimes I get just Square boxes instead of the actual thing that I want. I am making these images/texts in MS Word by converting the unicode to the actual image. I am also using various online resources to get these images/text.
Can anyone tell me how to get rid of the boxes and get the actual text.
My encoding is in UTF-8 and my font is also set to monospaced.
Your unicode-character is probably not supported by your font. Either the font implements the character as a box, or the operating system / font-renderer draws a box instead of the glyph.
I would say the Font used in your application just cannot show some chars. Find one which font really can and use it there.
Font has boolean canDisplay(char c) method which you can use.
See also the doc about font
I need to display some Bengali characters. I've tried to set the font to a Bengali Unicode font but It does not work properly. The last hope to fulfill my project is to use Character.UnicodeBlock. But I do not have any idea about it. Is it really possible to get the actual display of any Unicode character in Java? How can I use Character.UnicodeBlock in a component?
I assume Java 7.
First one needs a Unicode font.
If this font goes into the Windows fonts, and there is no name clash with an already existing font, everything should work.
Otherwise one might store the font as resource file in the application:
InputStream fontIn = getClass().getResourceAsStream("/.../... .ttf");
Font font = Font.createFont(Font.TRUETYPE_FONT, file);
GraphicsEnvironment.getLocalGraphicsEnvironment().registerFont(font);
After this jEditorPane.setFont(font) should work. Mind, the text in the JEditorPane should not be HTML, where own fonts might be set.
It is tricky, because of font substitution, on font decoding using names.
Another problem might be hard-coded strings in the java source: the encoding of the java source (the editor) must be the same as is used by the javac compiler. For international projects best both UTF-8 (javac -encoding=UTF-8 ...). To test whether there is a problem with that one can test with "\u099C" for জ.
For a play button in a Java GUI I currently use a button with the label set to ' ▻ ' (found this symbol in a Unicode symbol table). As I understand, it is better to not use such symbols directly in source code but rather use the explicit unicode representation like \u25BB in this example, because some tools (editor, ...) might not be able to handle files with non-ASCII content (is that correct?).
Assuming the compiled class contains the correct character, under which circumstances would the GUI not show the intended symbol on a current PC operating system? Linux, Windows, Mac should all support UTF-16, right? Do available fonts or font settings cause problems to this approach?
(Of course I could add an icon, but why add extra resources if a symbol should already be available... given that this is a portable solution)
Do available fonts or font settings cause problems to this approach?
Unfortunately they do. You can use unicode in the source code of course, but the problem is that currently unicode has 246,943 code points assigned so obviously no font has even a fraction of those defined. You'll get squares or some other weird rendering when the glyph isn't available. I've had cases where relatively simple symbols such as ³ render fine on one Windows computer and show up as squares in the next, almost identical computer. All sort of language and locale settings and minor version changes affect this, so it's quite fragile.
AFAIK there are few, if any, characters guaranteed to be always available. Java's Font class has some methods such as canDisplay and canDisplayUpTo, which can be useful to check this at runtime.
Instead of using icons, you could bundle some good TrueType font that has the special characters you need, and then use that font everywhere in your app.
I currently use a button with the label set to ' ▻ '
rather than I always use JButton(String text, Icon icon), and Icon doesn't matter if is there this Font or another Font, UTF-16 or Unicode
Most of editors have support for unicode, so go on.
Look at this post: Eclipse French support
If you are using simple editor like notepad then when you save type name and below it choose UTF encoding ( http://www.sevenforums.com/software/72727-how-make-notepad-save-txt-files-unicode.html )
In my Java application I want to output striked letters (like html tag do). Is there any way to do this using Unicode (combine )
You can use U+0336, the combining long stroke overlay, to accomplish this task.
The official Combining Diacritical Marks unicode chart lists "strikethrough" as an 'informative alias', meaning that this is is the official specified purpose of this character.
0336 ̶◌ COMBINING LONG STROKE OVERLAY
= strikethrough
• connects on left and right
For comparison, here is U+0336 compared to the html <strike> tag:
U̶n̶i̶c̶o̶d̶e ̶c̶o̶m̶b̶i̶n̶i̶n̶g̶ ̶l̶o̶n̶g̶ ̶s̶t̶r̶o̶k̶e̶ ̶o̶v̶e̶r̶l̶a̶y̶
Hypertext strike tag
Note that many font rendering engines do not render U+0336 correctly, and when possible one should use markup formatting or another mechanism. Depending on your browser, the above text likely has a large gap in the line around the "m" in combining, and #Alex78191 reports that it renders so low for them that it looks more like an underline than a strikethrough.
For this reason, one should still prefer HTML another markup technology over U+0336 for this purpose, given the option.
No, this is not possible. While there is the concept of a stroke as diacritic, it's not available as a separate Unicode character, probably because the various letters that use a stroke diacritic do not place it at the same height or even angle. So the result would not resemble strikethrough markup anyway.
To output strikethrough text in Java, you need to use an output format that allows you to use explicit markup. If you have a Swing app, you're in luck as many Swing components support HTML. Otherwise it depends on what presentation technology you're using.
As said before, Unicode doesn't do that, but a lot of Swing components understand basic HTML tags.
JLabel label = new JLabel("<html><s>My stroke</s></html>")
No. Unicode does not define a combining strikeout mark. Unicode's view is that this is the job of markup -- like HTML.