我有一个 JTextField，它的大小可能会因分辨率而异。JTextField 将包含一个 3 个字母的字符串。
我想以这样一种方式设置 JTextField 的字体大小，以最大化字体大小，同时仍然完美地使文本适合 JTextField 内部。
有没有算法可以做到这一点？
问问题
1226 次
3 回答
2
给定字体大小中字符串的宽度a为x. 可用空间为s。然后你显然可以使用 factor: 来放大你的字体s / x。所以选择a * s / x字体大小。要知道x，用任意字体大小计算字符串的宽度a。
于 2013-10-15T21:56:37.467 回答
1
是的，我知道这是一个古老的线程......但我只是遇到了类似的问题并创建了自定义 JTextField 类来解决它。此类使用一些“校准文本”，这是我的实现所独有的，但对于其他用途很容易更改。
因此，它将在两种情况下更改字体：
- 控件已调整大小 - 使用静态“校准文本”来确定大小
- 文本更改 - 根据当前文本动态调整文本大小（向上和向下）
public class DynamicText extends JTextField implements ComponentListener
{
private final int MIN_SIZE = 5;
private final int MAX_SIZE = 100;
private int pfvMinFontSize = 5; // minimum font size
private int pfvMaxFontSize = 100; // maximum font size
private boolean pfvAutoScale = true; // enabled the autoscaling feature
int cached_width = 0;
int cached_height = 0;
int widthLimitPixels;
float calcMax;
public DynamicText()
{
super();
this.getDocument().addDocumentListener(new TextChanged(this));
addComponentListener(this);
}
public DynamicText(int cols)
{
super(cols);
this.getDocument().addDocumentListener(new TextChanged(this));
addComponentListener(this);
}
public int getMinFontSize()
{
return pfvMinFontSize;
}
public void setMinFontSize(int val)
{
if (val >= MIN_SIZE)
{
pfvMinFontSize = val;
}
}
public int getMaxFontSize()
{
return pfvMaxFontSize;
}
// TODO: Check to make sure max is larger than min
public void setMaxFontSize(int val)
{
if (val <= MAX_SIZE)
{
pfvMaxFontSize = val;
}
}
public boolean getAutoScale()
{
return pfvAutoScale;
}
public void setAutoScale(boolean val)
{
pfvAutoScale = val;
}
@Override
public void componentResized(ComponentEvent e)
{
// to keep from having to process multiple events
if (this.getWidth() != cached_width || this.getHeight() != cached_height)
{
cached_width = this.getWidth();
cached_height = this.getHeight();
/*
* I do not consider this part of the optional AutoScale feature
* since this will just scale the font for the "calibrated"
* text this the maximum size
*/
Font ft = this.getFont();
float fontSize = pfvMinFontSize;
FontMetrics metrics;
int widthPixels = 0;
int widthLimitPixels = this.getWidth() - this.getMargin().left - this.getMargin().right;
float calcMax = (this.getHeight() - this.getMargin().top - this.getMargin().bottom) / 1.5f;
while (widthPixels < widthLimitPixels && fontSize <= pfvMaxFontSize && fontSize <= calcMax)
{
++fontSize;
Font temp = ft.deriveFont(fontSize);
metrics = this.getFontMetrics(temp);
widthPixels = metrics.stringWidth("00000000 00000000 00000000 00000000 .b.");
}
--fontSize;
this.setFont(ft.deriveFont(fontSize));
}
}
@Override
public void componentMoved(ComponentEvent e)
{
// nothing
}
@Override
public void componentShown(ComponentEvent e)
{
// nothing
}
@Override
public void componentHidden(ComponentEvent e)
{
// nothing
}
private class TextChanged implements DocumentListener
{
JTextField jtf;
public TextChanged(JTextField source)
{
jtf = source;
}
@Override
public void insertUpdate(DocumentEvent e)
{
resizeFont();
}
@Override
public void removeUpdate(DocumentEvent e)
{
resizeFont();
}
@Override
public void changedUpdate(DocumentEvent e)
{
// not applicable here...
}
private void resizeFont()
{
if (pfvAutoScale && jtf.getHeight() > 0)
{
Font ft = jtf.getFont();
String viewText = jtf.getText();
float fontSize = pfvMinFontSize;
FontMetrics metrics;
int widthPixels = 0;
int widthLimitPixels = jtf.getWidth() - jtf.getMargin().left - jtf.getMargin().right;
float calcMax = (jtf.getHeight() - jtf.getMargin().top - jtf.getMargin().bottom) / 1.5f;
while (widthPixels < widthLimitPixels && fontSize <= pfvMaxFontSize && fontSize <= calcMax)
{
++fontSize;
Font temp = ft.deriveFont(fontSize);
metrics = jtf.getFontMetrics(temp);
widthPixels = metrics.stringWidth(viewText);
}
--fontSize;
jtf.setFont(ft.deriveFont(fontSize));
}
}
}
}
于 2021-06-02T02:16:04.540 回答
0
我使用了 Martijn 的答案以及以下答案：
...为了写下我的问题的完整答案。就这样吧。感谢所有做出贡献的人。
您将需要导入以下内容：
import javax.swing.JTextField;
import java.awt.Font;
import java.awt.image.BufferedImage;
import java.awt.FontMetrics;
import java.lang.Math;
...................................
public int getFontSize(JTextField text, int columnsToHold){
//Create a sample test String (we will it later in our calculations)
String testString = "";
for(int i = 0; i<columnsToHold; i++){
testString = testString + "5";
}
//size will hold the optimal Vertical point size for the font
Boolean up = null;
int size = text.getHeight();
Font font;
while (true) {
font = new Font("Default", 0, size);
int testHeight = getFontMetrics(font).getHeight();
if (testHeight < height && up != Boolean.FALSE) {
size++;
up = Boolean.TRUE;
} else if (testHeight > height && up != Boolean.TRUE) {
size--;
up = Boolean.FALSE;
} else {
break;
}
}
//At this point, size holds the optimal Vertical font size
//Now we will calculate the width of the sample string
BufferedImage img = new BufferedImage(1, 1, BufferedImage.TYPE_INT_ARGB);
FontMetrics fm = img.getGraphics().getFontMetrics(font);
int width = fm.stringWidth(testString);
//Using Martijn's answer, we calculate the optimal Horizontal font size
int newFontSize = size * textos[0].getWidth()/width;
//The perfect font size will be the minimum between both optimal font sizes.
//I have subtracted 2 from each font so that it is not too tight to the edges
return Math.min(newFontSize-2, size-2);
}
于 2013-11-13T04:01:38.947 回答