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RichTextBox not showing the text

I am trying to create a Bitmap from a RichTextBox and set it as the background image for a panel, but unfortunately the text is not shown.
Bitmap l_bitmap = new Bitmap(m_control.Width, m_control.Height);
m_control.DrawToBitmap(l_bitmap, new Rectangle(0, 0, l_bitmap.Width, l_bitmap.Height));
m_panel.BackgroundImage = l_bitmap;
m_panel.Refresh();
m_control is my RichTextBox. When I debug, I can see that the control contains the text I wrote, but the bitmap just shows an empty RichTextBox.
I use the same code for other types of controls (Button, CheckBox, TextBox...). The text is shown with no problems.

Well you are trying to create a bitmap from the control. The text you put in there isn't the control, so it won't bother to chow it as bitmap. Try to create a picture from screen (like a screenshot).
Example:
Graphics gr = Graphics.FromImage(l_bitmap);
gr.CopyFromScreen(m_control.PointToScreen(Point.Empty), point.Empty, m_control.Size);
This will make a bitmap from your given points. This will additional show you the text.
EDIT
Maybe you can use this instead. In addition to your idea, I simply put a label onto my panel. (L for Label and P for Panel)
As you can see, the label is empty because I cleared the Text property. Now, when you click one of the buttons below the panel, it will update the label.Text propertie and there will be the text you gave the control.
Here is some example:
As you can see, the label shows the Name of the control. Completly custom as you can see on my source code:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public RichTextBox tmpRtf = new RichTextBox();
//Poor button name incoming...
private void button1_Click(object sender, EventArgs e)
{
if (tmpRtf == null)
tmpRtf = new RichTextBox();
//You can add any text here and it will be shown on the label.
this.tmpRtf.Text = "Richtextbox";
this.UpdatePanel(this.tmpRtf);
}
//Custom method to update the panel for any control. Can pobably be done way better than this, but hey.
private void UpdatePanel(object pControl)
{
//Checks if control is a rtf
if(pControl is RichTextBox)
{
//This is your code! Ay.
Bitmap l_bitmap = new Bitmap(this.panel1.Width / 2, this.panel1.Height / 2);
(pControl as RichTextBox).DrawToBitmap(l_bitmap, new Rectangle(0, 0, l_bitmap.Width, l_bitmap.Height));
this.tmpRtf.BackColor = Color.LightGray;
this.panel1.BackgroundImage = l_bitmap;
this.panel1.BackgroundImageLayout = ImageLayout.Center;
this.labelControlName.Text = this.tmpRtf.Text;
this.panel1.Refresh();
}
}
}
Its not possible to show text on a control thats not visualized. But you can build a workaround! Or, instead of taking a picture you can simply create the control on top of it, that will also show the Text and maybe the user can test it (e.g. click on buttons, look at the control behaviour).
Hopefully this is something to get you inspired that there are always more ways to accomplish.

Can't Add Tab Page To TabControl Inside The Constructor Of My WinForms Application

I have a C# Form application that has a TabControl in the main form. This TabControl is used to display multilple TabPages that contain a CustomControl. This CustomControl is just a Panel with a few buttons and a PictureBox.
Here is a picture of my app when it starts up. As you can see the tab control (the white area) is empty:
If the user clicks the "Add Image" button they are presented with an OpenFileDialog to select the image then the addImage method is called with the selected file:
private void doAddImage()
{
OpenFileDialog openFileDialog = new OpenFileDialog();
openFileDialog.Filter = Constants.Global.IMAGE_FILE_FILTER();
if (openFileDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
string imageFileName = openFileDialog.FileName;
addImage(imageFileName);
}
}
private void addImage(string imageFileName)
{
// Create a new bitmap and image preview custom control. Then create a new tab
// page and add the custom control to the tab page.
Bitmap bitMap = new Bitmap(imageFileName);
ImagePreviewCustomControl previewControl = new ImagePreviewCustomControl(bitMap);
previewControl.Dock = DockStyle.Fill;
TabPage tabPage = new TabPage(Path.GetFileNameWithoutExtension(imageFileName));
tabPage.Controls.Add(previewControl);
// Insert the new tab page to the right of the currently selected tab page
int selectedTabIndex = imagesTabControl.SelectedIndex;
imagesTabControl.TabPages.Insert(selectedTabIndex + 1, tabPage);
imagesTabControl.SelectedIndex = selectedTabIndex + 1;
}
As you can see, in the addImage method I create the Bitmap, CustomControl, and TabPage and then insert it into the TabControl.
I start my application, click the "Add Image" button, everything works just fine.
Here is a picture with a tab page added:
While I am testing my app I don't want to have to add an image manually using the OpenFileDialog every time so in my constructor I just call addImage with some fixed image file name that I want to test with:
public ImageViewerApp()
{
InitializeComponent();
addImage(#"C:\MyImages\Calculator-3-icon.png");
}
The problem I am having is that when I try to add the image in my constructor it doesn't show up in the TabControl. The application starts up blank (like the first picture).
As stated above when the application is already running and I click the "Add Image" button it gets added just fine.
I found a property in the TabControl class called Created which states:
"Gets a value indicating whether the control has been created"
So to try and figure out what's going on I write the value of Created to the console just before I call addImage in the constructor. (I have a custom console for debugging my Form applications.)
public ImageViewerApp()
{
InitializeComponent();
TestConsole.WriteLine(imagesTabControl.Created);
addImage(#"D:\Development\Work\Other\Stardock\Start8\_downloaded\Calculator-3-icon.png");
}
The value of Created just before the call to addImage in the constructor is:
False
I put another console output inside the addImage method:
private void doAddImage()
{
TestConsole.WriteLine(imagesTabControl.Created);
OpenFileDialog openFileDialog = new OpenFileDialog();
...
...
}
The value of Created after the app has started and the user presses the "Add Image" button is:
True
Why is it that the TabControl is not Created inside my constructor (even after the InitializeComponent() call) and the once the application is running it is Created?
=UPDATE========================================================================
Based on the suggestion by Hans Passant I have added the following code to my addImage method:
int selectedTabIndex = -1;
if (imagesTabControl.TabCount > 0)
{
selectedTabIndex = imagesTabControl.SelectedIndex;
}
else
{
selectedTabIndex = imagesTabControl.SelectedIndex + 1;
}
imagesTabControl.TabPages.Insert(selectedTabIndex, tabPage);
imagesTabControl.SelectedIndex = selectedTabIndex;
This doesn't work.
===============================================================================
=UPDATE2=======================================================================
int selectedTabIndex = imagesTabControl.SelectedIndex;
if (imagesTabControl.TabCount == 0) selectedTabIndex = -1;
imagesTabControl.TabPages.Insert(selectedTabIndex, tabPage);
imagesTabControl.SelectedIndex = selectedTabIndex;
This causes the following Exception:
{"InvalidArgument=Value of '-1' is not valid for 'index'.\r\nParameter name: index"}
===============================================================================
=UPDATE3=======================================================================
I tried the folllowing code:
int selectedTabIndex = imagesTabControl.SelectedIndex;
if (imagesTabControl.TabCount == 0) selectedTabIndex = -1;
imagesTabControl.TabPages.Insert(selectedTabIndex + 1, tabPage);
imagesTabControl.SelectedIndex = selectedTabIndex + 1;
This one doesn't throw an exception but again no tab page added after calling
addImage in the constructor.
===============================================================================
=UPDATE4=======================================================================
I have kindof given up on adding an image in the constructor. So instead I am using an enum RunMode and a variable RUN_MODE of that type. Then, if RUN_MODE == RunMode.TESTI call a method to add a random image when I click the button. (The OpenFileDialog is not used. I just parse through all the image files in the fixed directory IMAGE_DIRECTORY.
enum RunMode { NORMAL, TEST }
private static string IMAGE_DIRECTORY = #"D:\\Work\Images";
...
...
private void doAddImage()
{
if (RUN_MODE == RunMode.TEST)
{
addRandomImage();
return;
}
OpenFileDialog openFileDialog = new OpenFileDialog();
openFileDialog.Filter = Constants.Global.IMAGE_FILE_FILTER();
if (openFileDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
string imageFileName = openFileDialog.FileName;
addImage(imageFileName);
}
}
private void addRandomImage()
{
string[] allFiles = Directory.GetFiles(IMAGE_DIRECTORY);
List<string> imageFileNames = new List<string>();
foreach (string file in allFiles)
{
bool isImageFile = Constants.Global.IMAGE_EXTENSIONS.Contains(Path.GetExtension(file));
if (isImageFile)
{
imageFileNames.Add(file);
}
}
int randomIndex = new Random().Next(imageFileNames.Count);
addImage(imageFileNames.ElementAt(randomIndex));
}
This works. Now when I click the "Add Image" button during TEST_MODE I skip the
OpenFileDialog and just add a random image.
I would like to understand the issues with TabControl but at this point I just
need to continue development. My current solution works great.
As I person who like to understand everything I would like to use other people's
suggestions so I will keep monitoring this question for a solution.
===============================================================================

JonP's answer gave me the idea to just wait for the window handle to be created before inserting the tab, so I tried some events occuring between Form construction and Tab Control display.
I found it to work with both the Load or Shown events:
Right-click on the Form (the root, not child controls) in the Designer view > Properties > Events (flash icon) > Behavior > enter a method name for the Load or Shown event and confirm. To generate a Load event callback you can also double-click on the Form itself. This should generate something like this:
this.Load += new System.EventHandler(this.Form1_Load);
// or
this.Shown += new System.EventHandler(this.Form1_Shown);
Setup the tabs in the callback:
private void Form1_Load(object sender, EventArgs e)
{
// Add image (this will call imagesTabControl.TabPages.Insert(selectedTabIndex + 1, tabPage))
// This must be done on Load event because Insert requires
// the window handle, which is not ready in the constructor
addImage(#"path_to_image.png");
}

I have had this problem too and have found a workaround; I think it must be a bug with Insert():
Don't use Insert(), it usually does nothing, use Add() instead; this reliably adds a TabPage to the end of the collection.
After adding it swap it with the tab position where you actually want it.
imagesTabControl.TabPages.Add(tabPage);
// Now swap the two tabs:
imagesTabControl.TabPages[imagesTabControl.TabCount - 1] = imagesTabControl.TabPages[selectedTabIndex + 1];
imagesTabControl.TabPage[selectedTabIndex + 1] = tabPage;
Your mileage may vary of course :-)
Stop Press! An even better fix is to read the class's Handle member before calling Insert():
var handle = imagesTabControl.Handle;
Insert() works perfectly after you do that. Obvious isn't it???? The help page for Handle has this possible relevant Remark showing that the object actually does something when you read Handle:
The value of the Handle property is a Windows HWND. If the handle has not yet been created, referencing this property will force the handle to be created.

You could remove the TabControl from the designer and then instead just manually create the TabControl programmatically and add it to the Form immediately after InitializeComponent(). Then after you create the TabControl, call addImage(). Something like:
InitializeComponent();
TabControl tc = new TabControl();
tc.Location = new Point(10, 10);
tc.Size = new Size(100, 100);
tc.Visible = true;
tc.Anchor = (AnchorStyles.Bottom | AnchorStyles.Right | AnchorStyles.Left | AnchorStyles.Top);
this.Controls.Add(tc)
addImage("c:\pathToImage\image.bmp");

Clickable image grid in windows form?

If this is a dumb question, forgive me. I have a small amount of experience with C#, but not to this degree yet.
I have a series of images that I want to put into a grid with space around each image, also text beneath them and I want them to be clickable, so when they're clicked they hilite, and double click runs an event. The best example I have for this is the user interface of the program ACDSee. I've googled this for hours, and haven't come up with anything applicable. Is this difficult or simple? Can anyone give me an example, or point me in the right direction?
Cheers.

It doesn't seem to be very difficult. I would suggest the following steps:
Add a new "User Control" to your project for image thumbnails. It can contain a docked PictureBox and a Label or LinkLabel at its bottom.
For the space around each thumbnail simply play with the Padding property of the user control.
For the so called grid that is going to hold the thumbnails, use a FlowLayoutPanel, and simply add instances of the above mentioned user-control to this panel.
For visual representation of being selected, change the background color of the user-control instance to blue (for example), and back to control-face when deselected. It is recommended to implement an IsSelected property for the user-control as well.
To emulate thumbnail selection, handle the Click event of the user-control and assign the events for all thumbnail instances to a single event-handler method. Store a global reference to the already selected thumbnail, name it e.g., SelectedThumbnail initialized with null. In the event-handler body compare the sender with the global SelectedThumbnail, and update it if required. If the user-control associated with the sender is not selected (i.e., its background is not blue, or IsSelected is false) make it selected, or change its background. Otherwise change the background to its default color (e.g., control-face).
The Click event handler body looks something like this:
MyThumbnailControl ctrl = sender as MyThumbnailControl;
if(ctrl == null) return;
if(ctrl == SelectedThumbnail) return; // selected again
if(ctrl != SelectedThumbnail)
{
ctrl.IsSelected = true;
ctrl.BackColor = Color.Blue;
// it's better to set the back-color in the IsSelected property setter, not here
SelectedThumbnail.IsSelected = false;
SelectedThumbnail.BackColor = Color.Control;
SelectedThumbnail = ctrl; // important part
}
It's also recommended that all thumbnail instances that are going to be added to the so-called grid, be referenced in a separate array too. Therefore changing selection with arrow-keys would be possible with simple index calculations.
Further Notes: I assumed that the user-control that is to be created is named MyThumbnailControl, just a random name to refer to that control. When you create a new user-control, the wizard generates a class for you with your desired name (e.g., MyThumbnailControl), you can define a property inside it named IsSelected and implement its getter and setter. See this for a tutorial. After defining the user-control you can instantiate instances from its corresponding class. Also by global reference, I meant a variable at the form (or any parent control) level. To keep it simple we can add a reference of the selected thumbnail in the form that is going to hold the grid and thumbnails: MyThumbnailControl selectedThumb = null; or something like this in the body of the form.

Here is something, I just fixed you.
Create a C# project name CreateImageList and in the Form1 add the following 5 controls with their default name i.e. Panel1, PictureBox1, Label1, Button1, Button2:
How it works:
When the page load it create an imageList objects and load all .jpg images from a folder you provide
ImageList Images are set into the PictureBox control and when user clicks "Button1" the picturebox shows next image in ImageList and when user clicks "Button2" the PictureBox shows previous image from ImageList.
The Label1 shows the currentImage counter from the ImageList Arrage. If you want to write something specific, you can create an array of text and sync with your image counter.
When user click on PictureBox the a border is create to show Picture highlighted
When user Double Click on PictureBox a MessageBox appears shows DoubleClick event.
Now, you can use the following code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
namespace CreateImageList
{
public partial class Form1 : Form
{
private int currentImage = 0;
protected Graphics myGraphics;
ImageList iPicList = new ImageList();
public Form1()
{
InitializeComponent();
DirectoryInfo dirImages = new DirectoryInfo("C:\\2012");
iPicList.ImageSize = new Size(255, 255);
iPicList.TransparentColor = Color.White;
myGraphics = Graphics.FromHwnd(panel1.Handle);
foreach (FileInfo file in dirImages.GetFiles())
{
if (file.Extension == ".jpg")
{
Image myImage = Image.FromFile(file.FullName);
iPicList.Images.Add(myImage);
}
}
if (iPicList.Images.Empty != true)
{
panel1.Refresh();
currentImage = 0;
// Draw the image in the panel.
iPicList.Draw(myGraphics, 1, 1, currentImage);
// Show the image in the PictureBox.
pictureBox1.Image = iPicList.Images[currentImage];
label1.Text = "Image #" + currentImage;
}
}
private void showImage(int imgIndex)
{
// Draw the image in the panel.
iPicList.Draw(myGraphics, 1, 1, currentImage);
// Show the image in the PictureBox.
pictureBox1.Image = iPicList.Images[currentImage];
label1.Text = "image #" + currentImage;
panel1.Refresh();
}
private void button1_Click(object sender, EventArgs e)
{
if (iPicList.Images.Count - 1 > currentImage)
{
currentImage++;
}
else
{
currentImage = 0;
}
showImage(currentImage);
}
private void button2_Click(object sender, EventArgs e)
{
if (iPicList.Images.Count - 1 >= currentImage)
{
if (currentImage == 0)
currentImage = iPicList.Images.Count-1;
else
currentImage--;
}
else
{
currentImage = iPicList.Images.Count;
}
showImage(currentImage);
}
private void pictureBox1_DoubleClick(object sender, EventArgs e)
{
MessageBox.Show("Picture Box Double clicked");
}
private void pictureBox1_Click(object sender, EventArgs e)
{
panel1.Refresh();
myGraphics.DrawRectangle(Pens.Black, 0, 0, iPicList.Images[currentImage].Width + 1, iPicList.Images[currentImage].Height + 1);
pictureBox1.Image = iPicList.Images[currentImage];
}
}
}
The changes you need are:
Change the Following folder to a place where you have lots of jpg:
DirectoryInfo dirImages = new DirectoryInfo("C:\\2012");
Also if you are dealing with other kind of images, make change here:
if (file.Extension == ".jpg") // Change it to your image type.
If you don't want to use the the buttons to go up and down, you have several other options to host PictureBox control in scrollable Panel or list or something else.

Enable a button to be clicked at design-time in Visual Studio?

My setting:
I've got a C# application (.NET 3.5) in Visual Studio 2008. No chance to switch to WPF or whatsoever :).
My app contains a custom control (a button class derived from Windows.Forms.Button) that acts as a replacement for the Windows.Forms.TabControl. I can associate these buttons with one another and each button can be associated with one control that it is dealing with (usually some sort of Windows.Forms.Panel). It looks something like this:
public class TabButton : System.Windows.Forms.Button
{
// ...
protected override void OnClick(EventArgs e)
{
base.OnClick(e);
this.myAssociatedControl.Visible = true;
this.tellMyBuddiesToHideTheirControls();
}
// ...
}
Basically it is just about clicking a button, showing its bound control and having the controls bound to the associated buttons disappear - just like the TabControl, but the approach is easily designable and I can place the buttons far from their content panels.
The problem:
This works pretty well at runtime, but the usage at design time is arguably odd: With the mouse, find a control that´s belonging to the group and run a series of <Send To Back>s until the desired control is visible.
The question:
Is there a way to tell the VS designer to evaluate the clicks on the buttons at design time like it does with the TabControl so that I can switch the tabs just by clicking them like I would at runtime?
I've been searching for quite a while now. There are some articles here at SO but they only seem to cover adding additional attributes to the properties designer.

Edith says:
By request, an answer to my own question ...
This is the solution that is suitable to my application. It is basically an example from the msdn with some twists to get the custom designer to use a callback on click. Hope it helps anyone :-).
[System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name = "FullTrust")]
public class TabButtonDesigner : System.Windows.Forms.Design.ControlDesigner
{
ShowTabGlyph myGlyph = null;
Adorner myAdorner;
public TabButtonDesigner()
{
}
public override void Initialize(IComponent component)
{
base.Initialize(component);
// Add the custom set of glyphs using the BehaviorService.
// Glyphs live on adornders.
myAdorner = new Adorner();
BehaviorService.Adorners.Add(myAdorner);
myGlyph = new ShowTabGlyph(BehaviorService, Control);
myGlyph.Callback = () =>
{
((MyCustomTabButton)this.Control).ShowMyTab();
};
myAdorner.Glyphs.Add(myGlyph);
}
class ShowTabGlyph : Glyph
{
Control control;
BehaviorService behaviorSvc;
public Action Callback
{
get;
set;
}
public ShowTabGlyph(BehaviorService behaviorSvc, Control control) :
base(new ShowTabBehavior())
{
this.behaviorSvc = behaviorSvc;
this.control = control;
}
public override Rectangle Bounds
{
get
{
// Create a glyph that is 10x10 and sitting
// in the middle of the control. Glyph coordinates
// are in adorner window coordinates, so we must map
// using the behavior service.
Point edge = behaviorSvc.ControlToAdornerWindow(control);
Size size = control.Size;
Point center = new Point(edge.X + (size.Width / 2),
edge.Y + (size.Height / 2));
Rectangle bounds = new Rectangle(
center.X - 5,
center.Y - 5,
10,
10);
return bounds;
}
}
public override Cursor GetHitTest(Point p)
{
// GetHitTest is called to see if the point is
// within this glyph. This gives us a chance to decide
// what cursor to show. Returning null from here means
// the mouse pointer is not currently inside of the glyph.
// Returning a valid cursor here indicates the pointer is
// inside the glyph, and also enables our Behavior property
// as the active behavior.
if (Bounds.Contains(p))
{
return Cursors.Hand;
}
return null;
}
public override void Paint(PaintEventArgs pe)
{
// Draw our glyph. It is simply a blue ellipse.
pe.Graphics.DrawEllipse(Pens.Blue, Bounds);
}
// By providing our own behavior we can do something interesting
// when the user clicks or manipulates our glyph.
class ShowTabBehavior : Behavior
{
public override bool OnMouseUp(Glyph g, MouseButtons button)
{
//MessageBox.Show("Hey, you clicked the mouse here");
//this.
ShowTabGlyph myG = (ShowTabGlyph)g;
if (myG.Callback != null)
{
myG.Callback();
}
return true; // indicating we processed this event.
}
}
}
}
[DesignerAttribute(typeof(TabButtonDesigner))]
public class MyCustomTabButton : System.Windows.Forms.Button
{
// The attribute will assign the custom designer to the TabButton
// and after a rebuild the button contains a centered blue circle
// that acts at design time like the button in runtime does ...
// ...
}

Moving panel with directshow video renderer in it

I have a few panels with different directshow IVideoWindow handles bound to them so that the videos get shown inside the panels (WindowStyle properties are: Child,ClipSiblings,ClipChildren,Caption) Now I would like to move these panels around but I can only manage to move them when the video content is not filling the entire panel and I'm clicking+holding mouse button on the empty panel space. I can move the video windows around in the panels but of course they only move inside their respective panel space.
Is there a way to bind the video window content directly to the panel , for example the entire panel with content moves freely around when I click+hold the videowindow menu bar?
Thanks in advance.
Forgot to mention,this is in c#.

I use the Video Mixing Renderer 9 and have it tied to a user control. I have set the VMR9 to Windowless mode and then set the video clipping window on the IVMRWindowlessControl9 interface to the handle of my user control. I also set the video to fill the panel completely, using IVMRWindowlessControl9.GetNativeVideoSize, IVMRWindowlessControl9.SetAspectRatioMode, and IVMRWindowlessControl9.SetVideoPosition whenever the panel gets resized. When the form that contains my user control gets moved around, the video follows along. This is all done with C# and DirectShow.NET.
Edited to add sample code:
public partial class VideoPanel : UserControl
{
private VideoMixingRenderer9 _renderer;
private IVMRWindowlessControl9 _windowlessControl;
public VideoMixingRenderer9 Renderer
{
get
{
return _renderer;
}
set
{
_renderer = value;
if (_renderer != null)
{
var filterConfig = _renderer as IVMRFilterConfig9;
if (filterConfig != null)
{
filterConfig.SetRenderingMode(VMR9Mode.Windowless);
_windowlessControl = _renderer as IVMRWindowlessControl9;
if (_windowlessControl != null)
{
_windowlessControl.SetVideoClippingWindow(Handle);
SetSize();
}
}
}
}
}
private void SetSize()
{
var srcRect = new DsRect();
var dstRect = new DsRect(ClientRectangle);
int arWidth, arHeight;
_windowlessControl.GetNativeVideoSize(out srcRect.right, out srcRect.bottom, out arWidth, out arHeight);
_windowlessControl.SetAspectRatioMode(VMR9AspectRatioMode.LetterBox);
_windowlessControl.SetVideoPosition(srcRect, dstRect);
}
}

I solved it finally and I can't believe how silly I was. I left out the
hr = videoWindow.put_MessageDrain(hWin.Handle);
line , of course the videowindow wouldnt "listen" to the panel.