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The MouseMove handler checks to see if a ball is grabbed and if the mouse is inside the client area, so that you cannot drag a ball off the screen. All being correct, it updates the position of the currently active ball. This method is found on lines 112–126.
Lastly, on lines 148–156 the Paint handler paints the balls on the surface of the form.
Reading and Writing RESX XML Files
Resource files, as we mentioned at the beginning of this chapter, come in several flavors—
.resources files and .resx files. Resx files are the raw, uncompiled XML used as a basic source form for resources. In the previous example, we showed the ResourceReader and
ResourceWriter classes. There are corresponding ResXResourceReader and
ResXResourceWriter classes that can be used to maintain the XML forms of the resources.
In our last example for this chapter, we’ve created a simple application that lets you load chosen bitmap, text, and icon files and convert these to a .RESX resource file (see Listing 3.4.8). The complexity of the task and the simplicity of this application show off some of the raw power of the Windows Forms architecture.
LISTING 3.4.8 ResXUtilForm.cs: The RESX Writer Utility
1:using System;
2:using System.Drawing;
3:using System.Collections;
4:using System.ComponentModel;
5:using System.Windows.Forms;
6:using System.Data;
7:using System.IO;
8:
9:/*
10:* NOTES: A bug in an early version of the .NET framework caused
11:* the program to raise an exception when the resource name is
12:* edited. In this file there are two sections of commented code
13:* that are designed to work around this problem
14:* If this code fails, simply uncomment the sections marked
15:* BUGFIXER and re-compile
16:*
17:*/
18:
19:namespace ResxUtil
20:{
21:/// <summary>
22:/// Summary description for Form1.
23:/// </summary>
24:public class ResXUtilForm : System.Windows.Forms.Form
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25:{
26:private System.Windows.Forms.ListView listView1;
27:private System.Windows.Forms.Button button1;
28:private System.Windows.Forms.Button button2;
29:private System.Windows.Forms.ImageList imageList1;
30:private System.Windows.Forms.ColumnHeader columnHeader2;
31:private System.Windows.Forms.ColumnHeader columnHeader1;
32:private System.ComponentModel.IContainer components;
34:public ResXUtilForm()
35:{
36://
37:// Required for Windows Form Designer support
38://
39:InitializeComponent();
40:
41://BUGFIXER uncomment the line below
42://this.listView1.LabelEdit=false;
43:}
44:
45:/// <summary>
46:/// Clean up any resources being used.
47:/// </summary>
48:protected override void Dispose( bool disposing )
49:{
50:if( disposing )
51:{
52:if (components != null)
53:{
54:components.Dispose();
55:}
56:}
57:base.Dispose( disposing );
58:}
59:
60:#region Windows Form Designer generated code
61:/// <summary>
62:/// Required method for Designer support - do not modify
63:/// the contents of this method with the code editor.
64:/// </summary>
65:private void InitializeComponent()
66:{
67:this.components = new System.ComponentModel.Container();
68:System.Resources.ResourceManager resources =
new System.Resources.ResourceManager(typeof(ResXUtilForm));
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108:this.listView1.KeyDown +=
new System.Windows.Forms.KeyEventHandler(this.listView1_KeyDown);
109:this.listView1.LabelEdit=true;
110://
111:// button1
112://
113:this.button1.Location = new System.Drawing.Point(696, 328);
114:this.button1.Name = “button1”;
115:this.button1.Size = new System.Drawing.Size(104, 32);
116:this.button1.TabIndex = 1;
117:this.button1.Text = “Save”;
118:this.button1.Click += new System.EventHandler(this.button1_Click);
119://
120:// button2
121://
122:this.button2.Location = new System.Drawing.Point(8, 328);
123:this.button2.Name = “button2”;
124:this.button2.Size = new System.Drawing.Size(88, 32);
125:this.button2.TabIndex = 2;
126:this.button2.Text = “Add...”;
127:this.button2.Click += new System.EventHandler(this.button2_Click);
128://
129:// ResXUtilForm
130://
131:this.AllowDrop = true;
132:this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
133:this.ClientSize = new System.Drawing.Size(816, 373);
134:this.Controls.AddRange(new System.Windows.Forms.Control[] {
135: |
this.button2, |
136: |
this.button1, |
137: |
this.listView1}); |
138:this.FormBorderStyle =
System.Windows.Forms.FormBorderStyle.FixedDialog;
139:this.Name = “ResXUtilForm”;
140:this.Text = “ResX Utility”;
141:this.ResumeLayout(false);
143:}
144:#endregion
146:/// <summary>
147:/// The main entry point for the application.
148:/// </summary>
149:[STAThread]
150:static void Main()
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195:can.DialogResult=DialogResult.Cancel;
196:can.Location=new Point(260,32);
197:can.Size=new Size(75,22);
198:can.Text=”Cancel”;
199:f.Controls.Add(can);
200:TextBox tb=new TextBox();
201:tb.Location=new Point(5,5);
202:tb.Size=new Size(330,25);
203:tb.Text=”Resource”+
204:((object)(this.listView1.Items.Count+1)).ToString();
205:f.Controls.Add(tb);
206:if(f.ShowDialog()==DialogResult.Cancel || tb.Text.Trim() == “”)
207:return;
208:resname=tb.Text.Trim();
209:*/
210:
211:
212:if(icon>=0)
213:{
214:ListViewItem item=new ListViewItem(resname,icon);
215:item.SubItems.Add(s);
216:this.listView1.Items.Add(item);
217:}
218:}
219:}
220:
221:private void button1_Click(object sender, System.EventArgs e)
222:{
223:if(this.listView1.Items.Count>0)
224:{
225://Check that all resources have a name
226:foreach(ListViewItem item in this.listView1.Items)
227:{
228:if(item.Text==”Undefined”)
229:{
230:MessageBox.Show(“All resources must have names”);
231:return;
232:}
233:}
234:
235://Fetch the filename for the resx file
236:SaveFileDialog dlg=new SaveFileDialog();
237:dlg.Title=”Save .resx file”;
238:dlg.Filter=”XML resource files|.resx”;
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283:}
284:}
286:rw.Generate();
287:rw.Close();
288:}
289:}
290:
291:
292:private void listView1_KeyDown(object sender,
293:System.Windows.Forms.KeyEventArgs e)
294:{
295:if(this.listView1.SelectedIndices.Count==0)
296:return;
297:if(e.KeyCode.Equals(Keys.Delete))
298:this.listView1.Items.RemoveAt(
299:this.listView1.SelectedIndices[0]);
300:}
301:}
302: 303: }
NOTE
Be aware that the style of layout in this and other listings has been modified to fit an 80 column format. In particular, the InitializeComponent method has been modified from its original form. If you download the file from the Sams Web site, it might differ slightly in layout, but it will be functionally identical.
By now, you should be able to go through the InitializeComponent and understand what’s happening, so we’ll just pick out highlights of the application.
Lines 79–80 create a set of column headers used when the ListView is in Detail mode to provide headers for each column of information. We have chosen to display the item icon from an ImageList plus the name of the resource, which you must choose, along with the full filename of the source resource.
Lines 89–92 set up the ImageList, bringing in the image stream and setting up sizes and transparent color and so on.
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Lines 98–100 add the column headers to the list view control. Lines 93–104 set the properties of the ListView to enable row selection (so you can delete an object from the list), label editing (which lets you name your resource, locations, and sizes for the control), and finally, the KeyDown handler (which only responds to the Delete key).
Lines 110–128 are the buttons. One adds a resource, the other saves the RESX file.
Lines 155–219 handle the Add button. This allows you to browse files (lines 154 and 155) for bitmaps, text, or icons. After you find a resource candidate, lines 168–179 decide whether it’s a file we care about and select the correct icon. Finally, lines 212–217 use the icon selection to create a ListViewItem that has a label (at first “Undefined”) and a sub-item that populates the second column of the list control with the filename.
The Save button on lines 221–284 does a quick check to see if all the resources have been named (lines 226–233) and then gets a filename for the target file (lines 236–240). Lines 243–244 make a new ResXResourceWriter and then pass it into a foreach loop that goes through item by item and creates the resources.
The switch statement (line 249) has three cases. Cases 0 and 2 are handled the same way because, for the XML format, there is no distinction between a bitmap and an icon. Case 1 (lines 254–276) reads in the text file one line at a time and separates the lines into the namevalue pairs used to create each text resource. The name is prefixed with the name you chose for the text file in the listbox. Note that this demonstration only understands text files with the “<name string>=<value string>” syntax. Other files are likely to give errors. After processing is done, lines 286 and 287 write and close the RESX file.
Finally, lines 292–300 handle the Delete key presses and remove items from the list if you want.
A Note about Bugs
Line 42 and the block of code on lines 184–208 are a contingency plan that solves a potential problem with an early version of the .NET framework. If you edit the resource name and the program crashes, uncomment the two sections of code in the lines marked “BUGFIXER” and recompile the program. It will work in a slightly different way, and it will not crash.
Notice also how the bugfix code creates a dialog box on-the-fly for you.
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NOTE
For applications built with Visual Studio, the complete solution is included as a zip archive on the Sams Web site (http://www.samspublishing.com).
Summary
In this chapter, you have seen how to create text resources by hand, how to internationalize applications using satellite assemblies, how to use Visual Studio to create applications with image and other resources, and how to dynamically create and use resource files in your programs. In the next chapter, we’ll be looking at the powerful graphics options available to you with GDI+.
