Adapt the height of a TextBox - c#

I am working on a UserControl that contains a multiline TextBox.
When using my control, one will be able to set the text that will be displayed. The TextBox should then adapt its Height to make the text fit, the Width cannot change.
So here is the property that handles the text :
[Editor(typeof(MultilineStringEditor), typeof(UITypeEditor))]
public string TextToDisplay
{
get
{
return internalTextBox.Text;
}
set
{
internalTextBox.Text = value;
AdaptTextBoxSize();
}
}
My first attempt was rather simple :
private void AdaptTextBoxSize()
{
int nbLignes = internalTextBox.Lines.Length;
float lineHeight = internalTextBox.Font.GetHeight();
internalTextBox.Height = (int)((nbLignes) * lineHeight);
}
This did not work as it doesn't take into account spacing between two lines of text. So the more lines I have in the text, the more I get clipped.
So I tried this :
private void AdaptTextBoxSize()
{
Size textSize = internalTextBox.GetPreferredSize(new Size(internalTextBox.Width, 0));
internalTextBox.Height = textSize.Height;
}
This does work when all the lines in the textbox are shorter than the Width. But when one line is longer and should be clipped to the next line, GetPreferredSize() returns a larger width than the one I passed, and therefore the height is too small.
So I changed again and tried this one:
private void AdaptTextBoxSize()
{
Size textSize = TextRenderer.MeasureText(
internalTextBox.Text,
internalTextBox.Font,
new Size(internalTextBox.Width, 0),
TextFormatFlags.WordEllipsis
);
internalTextBox.Height = textSize.Height;
}
This time the returned Width is correct, as it does not exceed the one I passed, but the height is the same as the previous trial. So it doesn't work either. I tried different combinations for TextFormatFlags, but could not manage to find the winning one...
Is this a bug from the framework?
The real question here is, is there another thing I can try, or another to achieve what I want (i.e. auto-adapt the height when setting the TextToDisplay property)?

TextBox.GetPositionFromCharIndex returns the pixel position of a character. Position here means top/left so we need to add one more line..
This seems to work here:
textBox.Height = textBox.GetPositionFromCharIndex(textBox4.Text.Length - 1).Y + lineHeight;
I get the line height like this:
int lineHeight = -1;
using (TextBox t = new TextBox() { Font = textBox.Font }) lineHeight = t.Height;
I set the Height instead of the ClientSize.Height, which is slightly wrong unless BorderStyle is None. You can change to textBox.ClientSize = new Size(textBox.ClientSize.Width, l + lh);

Related

Text scaling problem with itext7, hidden margins?

I'm trying to get this c# function from within a asp.netcore razor project using itext7 (7.1.7) to output a div containing text that scales up to within the constraints given with height and width. However, for some reason it seems there's some kind of hidden margin that will not scale the text to the boundaries of the given width and height, even though the margins are set to 0.
At the moment the maximum text i get is only half of what it should be.
Also, the paragraph, nor the div is actually set to the min width and min height.
Any help how to fix this is appreciated
public Div MakeScaledTxtDiv(string _displayTxt ,PdfFont _Pdffont, float _maxHeight,
float _maxWidth, Canvas _canvas, bool _showBorder)
{
Div nameDiv = new Div();
iText.Kernel.Geom.Rectangle posRect = new iText.Kernel.Geom.Rectangle(_maxWidth,_maxHeight);
Paragraph txtPara = new Paragraph()
.SetVerticalAlignment(VerticalAlignment.MIDDLE)
.SetTextAlignment(iText.Layout.Properties.TextAlignment.CENTER);
if (_showBorder)
txtPara.SetBorder(new DashedBorder(1));
if (_maxHeight > 0)
txtPara.SetMaxHeight(_maxHeight);
if (_maxWidth > 0)
txtPara.SetMaxWidth(_maxWidth);
txtPara
.SetMargin(0f)
.SetPadding(0f)
.SetFont(_Pdffont)
.Add(_displayTxt);
float fontSizeToSet = 1;
float fontSizeMax = 42;
float curFontSize = fontSizeMax;
bool m_bGoodfit = false;
while (!m_bGoodfit)
{
txtPara.SetFontSize(curFontSize);
ParagraphRenderer renderer = (ParagraphRenderer)txtPara.CreateRendererSubTree().SetParent(_canvas.GetRenderer());
LayoutContext context = new LayoutContext(new LayoutArea(1, posRect));
var fits = renderer.Layout(context).GetStatus();
if (fits == LayoutResult.FULL)
{
fontSizeToSet = curFontSize;
m_bGoodfit = true;
}
else
{
curFontSize -= 1;
if (curFontSize == 1)
{
fontSizeToSet = curFontSize;
m_bGoodfit = true;
}
}
}
txtPara.SetFontSize(fontSizeToSet);
if (_maxHeight > 0)
{
nameDiv.SetMinHeight(_maxHeight)
.SetMaxHeight(_maxHeight)
.SetHeight(_maxHeight);
}
if (_maxWidth > 0)
{
nameDiv.SetMinWidth(_maxWidth)
.SetMaxWidth(_maxWidth)
.SetWidth(_maxWidth);
}
nameDiv
.SetMargin(0f)
.SetPadding(0f)
.SetVerticalAlignment(VerticalAlignment.MIDDLE)
.SetTextAlignment(iText.Layout.Properties.TextAlignment.CENTER);
if (_showBorder)
nameDiv.SetBorder(new DottedBorder(1));
nameDiv.Add(txtPara).SetVerticalAlignment(VerticalAlignment.MIDDLE);
return nameDiv;
}
What worked for me was to change the multiplier number 0.7f slightly bigger in the code below (code referenced from https://stackoverflow.com/a/57929067/5490413).
It seems as that multiplier gets bigger/smaller, the space between the text and field bottom border grows/shrinks accordingly. Maybe start with 1.2f and find one that fits.
Paragraph linePara = new Paragraph().Add(lineTxt)
.SetTextAlignment(iText.Layout.Properties.TextAlignment.CENTER).SetBorder(new DottedBorder(1))
.SetMultipliedLeading(0.7f);
lineDiv.Add(linePara);
FYI I came across the exact issue you were facing: How to scale text within a fixed rectangle with itext7?
I tried with the answer posted there https://stackoverflow.com/a/57929067/5490413 and faced the same hidden bottom margin issue here.

Auto sized multi line text in a button

I have a button that needs the font size of the text to be changed based on how much text is in the button. This is changed dynamically during run-time.
Basically, the text needs to start fairly large, then it needs to test how much text is in the button and decide whether to go down in size or not. It could do this in a loop by decreasing the size by one, repainting, and testing each time to see if the text fits now. If not, loop again until it does.
But the problem is with testing it. The button has multi line text, and that's the way I want it. So I can't simply test the width of the text with the width of the button using something like TextRenderer.MeasureText, because that assumes the text will only be one line. It never measures based on if it can fit on two or more lines.
So if one line of text at a certain font is 40 pixels in height, even if its on 3 lines of text on the button, TextRenderer.MeasureText.Height will show 40 pixels. And with margins and padding on the button, and space between lines of text, I can't just do 40 * 3 to get how much 3 lines would be, it's not that simple.
So... how do I test whether or not the text in the button is too big for the button?
I could set Auto Ellipsis property to true, but there's no way to test to see if the Auto Ellipsis has been used or not. So that doesn't help.
I could set Auto Size to true and test to see if the button size changed, then bring it back to the right size and lower the text size, but, it resizes based on width, before it moves text to the second line, so it's always on one line. So that doesn't help.
Any ideas? I just want to auto size multi line text. It seems so simple.
Here is solutions for this for Windows Forms:
Set the starting size on TextBox than the size will be changed by this event handler.
private void textBox1_TextChanged(object sender, EventArgs e)
{
var textBox = sender as TextBox;
if(!string.IsNullOrEmpty(textBox.Text))
{
Graphics g = textBox.CreateGraphics();
var width = g.MeasureString("a", textBox.Font).Width;//Get One Symbol Width
var totalWidth = width * textBox.Text.Length; // Calculate the width of the full text
if(totalWidth<width*10) // do what you want depending on conditions
{
textBox.Font=new Font(textBox.Font.Name,20f);
}
else if(totalWidth < width * 20)
{
textBox.Font = new Font(textBox.Font.Name, 16f);
}
else if(totalWidth < width * 30)
{
textBox.Font = new Font(textBox.Font.Name, 14f);
}
else if (totalWidth < width * 40)
{
textBox.Font = new Font(textBox.Font.Name, 12f);
}
else if (totalWidth < width * 50)
{
textBox.Font = new Font(textBox.Font.Name, 10f);
}
}
}

Add padding to a TextObj item in a ZedGraph chart

Is it possible to add padding to a TextObj? I am looking to display a value on the chart, with a visible border, but the text is always too close to the border. Is it possible to extend the height/width of the box to always leave some space/padding?
I have tried updating the height/width of the box, but this doesn't appear to have any effect. I have also used empty string spaces and while this works on the left-hand side, it has no effect on the right side.
Is there a correct way to do this?
Try this,
public partial class Form1 : Form
{
GraphPane myPane;
public Form1()
{
InitializeComponent();
myPane = zedGraphControl1.GraphPane;
AddTxtObject();
}
private void AddTxtObject()
{
TextObj txtObj = new TextObj("ZedGraph Version 5.1.5.xxx", 0.7, 0.8, CoordType.PaneFraction, AlignH.Left, AlignV.Bottom);
txtObj.FontSpec.FontColor = Color.GreenYellow;
txtObj.FontSpec.Size = 10;
txtObj.FontSpec.Fill.Color = Color.Black;
txtObj.FontSpec.Border.Color = Color.Black;
txtObj.FontSpec.Border.Width = 25.0f;
myPane.GraphObjList.Add(txtObj);
zedGraphControl1.Refresh();
}
}
By changing font size & the border width, you may achieve padding effect with Zedgraph.

How can I keep the RadioButton text and an additional Label in alignment?

I'm working on a C# project using .NET 3.5 and Windows Forms. I need to design a decision step with multiple options that require a bit of explanatory text. For this, I want to have a set of RadioButtons to choose an option, followed by an additional Label each that contains the explanation.
I want to keep the label of the radio buttons and the label containing the explanatory text aligned - I've added red lines to the image to illustrate this. I could probably tweak some margins or other settings on the second label, but that would probably start to look weird as soon as the user chooses a different theme or changes some other settings. What is the canonical (and most robust) way to do this?
Your question boils down to two partial problems:
How large is the RadioButton (or the CheckBox when thinking ahead)..
How large is the gap between the glyph and the Text.
The first question is trivial:
Size s = RadioButtonRenderer.GetGlyphSize(graphics,
System.Windows.Forms.VisualStyles.RadioButtonState.CheckedNormal);
..using a suitable Graphics object. Note that I use the RadioButtonState CheckedNormal as I don't you want the Lables to align differently when the Buttons are checked or unchecked..
The second one is anything but trivial. The gap may or may not be constant and there is another gap to the left of the glyph! If I really wanted to get it right I guess I would write a routine to measure the text offset at startup:
public Form1()
{
InitializeComponent();
int gapRB = getXOffset(radioButton1);
int gapLB = getXOffset(label1);
label1.Left = radioButton1.Left + gapRB - gapLB;
}
Here is the measurement function. Note that is doesn't even use the Glyph measurement. Also note that it isn't enough to measure the text offset of the RadioButton. You also need to measure the offset of the Label!
int getXOffset(Control ctl)
{
int offset = -1;
string save = ctl.Text; Color saveC = ctl.ForeColor; Size saveSize = ctl.Size;
ContentAlignment saveCA = ContentAlignment.MiddleLeft;
if (ctl is Label)
{
saveCA = ((Label)ctl).TextAlign;
((Label)ctl).TextAlign = ContentAlignment.BottomLeft;
}
using (Bitmap bmp = new Bitmap(ctl.ClientSize.Width, ctl.ClientSize.Height))
using (Graphics G = ctl.CreateGraphics() )
{
ctl.Text = "_";
ctl.ForeColor = Color.Red;
ctl.DrawToBitmap(bmp, ctl.ClientRectangle);
int x = 0;
while (offset < 0 && x < bmp.Width - 1)
{
for (int y = bmp.Height-1; y > bmp.Height / 2; y--)
{
Color c = bmp.GetPixel(x, y);
if (c.R > 128 && c.G == 0) { offset = x; break; }
}
x++;
}
}
ctl.Text = save; ctl.ForeColor = saveC; ctl.Size = saveSize;
if (ctl is Label) { ((Label)ctl).TextAlign = saveCA; }
return offset;
}
Now the Texts do align pixel perfect..:
Note that I use two original controls from my form. Therefore much of the code is simply storing and restoring the properties I need to manipulate for the measurement; you can save a few lines by using two dummies.. Also note that I wrote the routine so that it can measure RadioButtons and Labels and probably CheckBoxes as well..
Is it worth it? You decide..!
PS: You could also owner-draw the RadioButton and the Label text in one.. this would have the interesting side-effect, that the whole text would be clickable..:
Here is a quick and dirty implementation of owner drawing a CheckBox: Prepare it by setting AutoSize = false and by adding the real text together with the extra text into the Tag, separated by a e.g. "§". Feel free to change this setup, maybe using the Label control..
I clear the Text to prevent it from drawing it and I decide on an offset. To measure it, you could use the GetGlyphSize from above.. Note how the DrawString method honors embedded '\n' characters.
The Tag contained this string:
A Rose is a Rose is a Rose..§A Rose is a rose is a rose is a rose is /
A rose is what Moses supposes his toes is / Couldn't be a lily or a
taffy daphi dilli / It's gotta be a rose cuz it rhymes with mose!
And I for the screenshot I actually used this line:
e.Graphics.DrawString(texts[1].Replace("/ ", "\n"), ...
Here is the Paint event:
private void checkBox1_Paint(object sender, PaintEventArgs e)
{
checkBox1.Text = "";
string[] texts = checkBox1.Tag.ToString().Split('§');
Font font1 = new Font(checkBox1.Font, FontStyle.Regular);
e.Graphics.DrawString(texts[0], checkBox1.Font, Brushes.Black, 25, 3);
if (texts.Length > 0)
{
SizeF s = e.Graphics.MeasureString(texts[1], checkBox1.Font, checkBox1.Width - 25);
checkBox1.Height = (int) s.Height + 30;
e.Graphics.DrawString(texts[1], font1, Brushes.Black,
new RectangleF(new PointF(25, 25), s));
}
}
The simplest out-of-the-box solution (it seems to me) would be to use 3 controls instead of 2: a radio button (with the text set to ""), a label (to go beside the radio button) and another label (to go below them). This would allow you easier configuration in designer, but (far more importantly) simpler run-time evaluation and adjustment, if necessary, to keep them in alignment should styles change.
I do understand that this takes away the benefit of clicking the label to select the radio button, but you could add that behavior in the label's Click event if you need it.
Alternatively, you could create a UserControl containing the text-free radio button and the label, and handle the behavior within that UserControl while exposing the label's location.
If you don't care about the radiobutton's text being bold, you could set it's label to a multiline string, and set CheckAlign to TopLeft:
radioButton2.CheckAlign = ContentAlignment.TopLeft;
radioButton2.Text = #"Radiobutton
Explanation text";
Don't know why I didn't think of this earlier, but the following approach seems to work:
Use a TableLayoutPanel with two columns that are set to adjust their width automatically.
Place all RadioButtons in the first column and set them to span both columns.
Place all Labels in the second column, setting all margins to 0.
Add a disabled, but visible (!) "spacer" RadioButton without text in an additional row at the end of the layout.
When displaying the form, convert the first column to a fixed size and hide the "spacer".
The key point seems to be that the "spacer" has to be visible initially - otherwise the column will get a size of 0.
This is my test form in the designer:
To change the layout, I used the following Load handler:
private void TestForm_Load(object sender, EventArgs e)
{
// find the column with the spacer and back up its width
int column = tableLayoutPanel.GetColumn(radioButtonSpacer);
int width = tableLayoutPanel.GetColumnWidths()[column];
// hide the spacer
radioButtonSpacer.Visible = false;
// set the column to the fixed width retrieved before
tableLayoutPanel.ColumnStyles[column].SizeType = SizeType.Absolute;
tableLayoutPanel.ColumnStyles[column].Width = width;
}
And this is the result at runtime:
You could add an invisible dummy label having the same text as the radiobutton. Then, get the length of that label and calculate the correct position of the explanation label.
labelDummy.Text = radioButton1.Text;
labelExplanation.Left = radioButton1.Right - labelDummy.Width;
However, this still appears to be some pixels off, even though I the label's margin to 0, maybe some additional tweaking can fix this. Here's a screenshot to show what I mean. The label's background is green to be able to see the extra margin.

AutoSize for Label / TextBox in .NET Compact Framework

I'm quite simply going totally bonkers with the omission of the AutoSize-property for the Label and TextBox controls in .NET Compact Framework. I have a simple app, that's supposed to list a bunch of text data (generally between one-liners to a few paragraphs of text) in a TabControl. Everything else works smoothly, but my attempts at dynamically resizing the Label / TextBox -controls I use to display the text are failing miserably.
Here's the way I've tried doing it:
/*
Variables:
s = The text intended for the TextBox
NewTB = TextBox object
width = Intended width
whiteSpaceAdjustment = amount of pixels per line to adjust "wasted" whitespace due to wrapping
*/
String[] linesArray = s.Replace(Environment.NewLine, "\n").Split(new char[] { '\n' });
int lines = 0;
int lineHeight = g.MeasureString(
s.Replace("\n", "").Replace("\r", ""),
LabelFont
).ToSize().Height;
foreach (String str in linesArray) {
if (str.Length == 0) {
lines++;
continue;
}
szz = g.MeasureString(str, LabelFont).ToSize();
lines += szz.Width / (width - whiteSpaceAdjustment);
lines += (szz.Width % width) != 0 ? 1 : 0;
}
NewTB.Height = lines * lineHeight;
NewTB.Width = width;
...but the problem is that the range needed for whiteSpaceAdjustment is too huge. When it's large enough to actually work on the most extreme cases (paragraphs made mostly up of really long words), most boxes end up being a line or two too tall.
I'm probably going to have to implement word wrapping myself, but before I go there, is there anybody with a nice clean solution ready for this?
I'd be forever grateful!
Try this article
www.mobilepractices.com/2007/12/multi-line-graphicsmeasurestring.html
Make sure you also look at the link at the bottom of the article to be able to use different fonts.
If you are using .Net CF 3.5 you may be able to turn their example into an extension method. Otherwise I'd suggest that you create a new control inheriting from the framework control.
This is what I developed for auto re-size width of label in WinCE.
/// <summary>
/// This class provides dynamic size labels, i.e. as the text grows lable width will grow with it.
/// </summary>
public partial class AutoSizeLabel : UserControl
{
private string _strText;
private const int padding = 10;
public AutoSizeLabel()
{
InitializeComponent();
}
public override string Text
{
get
{
return _strText;
}
set
{
_strText = value;
Refresh();
}
}
protected override void OnPaint(PaintEventArgs pe)
{
SizeF size = pe.Graphics.MeasureString(this.Text, this.Font);
this.Size = new Size((int)size.Width + padding, this.Height);
if (this.Text.Length > 0)
{
pe.Graphics.DrawString(this.Text,
this.Font,
new SolidBrush(this.ForeColor),
(this.ClientSize.Width - size.Width) / 2,
(this.ClientSize.Height - size.Height) / 2);
}
// Calling the base class OnPaint
base.OnPaint(pe);
}
}

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