simplify app initialization code

examples/example1/src/main.d

@@ -4,45 +4,22 @@ import dlangui.all;
 import std.stdio;
 import std.conv;
 
-version (linux) {
-	//pragma(lib, "png");
-	pragma(lib, "xcb");
-	pragma(lib, "xcb-shm");
-	pragma(lib, "xcb-image");
-	pragma(lib, "X11-xcb");
-	pragma(lib, "X11");
-	pragma(lib, "dl");
-}
 
-/// workaround for link issue when WinMain is located in library
-version(Windows) {
-    private import win32.windows;
-    private import dlangui.platforms.windows.winapp;
-    extern (Windows)
-        int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
-                    LPSTR lpCmdLine, int nCmdShow)
-        {
-            return DLANGUIWinMain(hInstance, hPrevInstance,
-                                  lpCmdLine, nCmdShow);
-        }
-}
+mixin APP_ENTRY_POINT;
 
 /// entry point for dlangui based application
 extern (C) int UIAppMain(string[] args) {
-    // setup resource dir
-	version (Windows) {
-    	string resourceDir = exePath() ~ "..\\res\\";
-    	string i18nDir = exePath() ~ "..\\res\\i18n\\";
-	} else {
-    	string resourceDir = exePath() ~ "../../res/";
-    	string i18nDir = exePath() ~ "../../res/i18n/";
-	}
-    string[] imageDirs = [
-        resourceDir
+    // resource directory search paths
+    string[] resourceDirs = [
+        appendPath(exePath, "../res/"),   // for Visual D and DUB builds
+        appendPath(exePath, "../../res/") // for Mono-D builds
     ];
-    drawableCache.resourcePaths = imageDirs;
-    i18n.resourceDir = i18nDir;
-    i18n.load("ru.ini", "en.ini");
+    // setup resource directories - will use only existing directories
+    drawableCache.setResourcePaths(resourceDirs);
+    // setup i18n - look for i18n directory inside one of passed directories
+    i18n.findTranslationsDir(resourceDirs);
+    // select translation file - for english language
+    i18n.load("en.ini"); //"ru.ini", "en.ini"
 
     // create window
     Window window = Platform.instance().createWindow("My Window", null);
@@ -162,9 +139,7 @@ extern (C) int UIAppMain(string[] args) {
 	    window.mainWidget = (new Button()).text("sample button");
 	}
     window.show();
-    //window.showPopup((new TextWidget()).text("POPUP"d));
-    window.windowCaption = "New Window Caption";
-
+    //window.windowCaption = "New Window Caption";
     // run message loop
     return Platform.instance().enterMessageLoop();
 }

src/dlangui/all.d

@@ -8,7 +8,33 @@ This module is just to simplify import of most useful DLANGUI modules.
 Synopsis:
 
 ----
+// helloworld
 import dlangui.all;
+// required in one of modules
+mixin DLANGUI_ENTRY_POINT;
+
+/// entry point for dlangui based application
+extern (C) int UIAppMain(string[] args) {
+    // resource directory search paths
+    string[] resourceDirs = [
+        appendPath(exePath, "../res/"),   // for Visual D and DUB builds
+        appendPath(exePath, "../../res/") // for Mono-D builds
+    ];
+    // setup resource directories - will use only existing directories
+    drawableCache.setResourcePaths(resourceDirs);
+    // setup i18n - look for i18n directory inside one of passed directories
+    i18n.findTranslationsDir(resourceDirs);
+    // select translation file - for english language
+    i18n.load("en.ini"); //"ru.ini", "en.ini"
+
+    // create window
+    Window window = Platform.instance().createWindow("My Window", null);
+    window.mainWidget = (new Button()).text("Hello world"d);
+    // run message loop
+    return Platform.instance().enterMessageLoop();
+}
+
+
 ----
 
 Copyright: Vadim Lopatin, 2014

src/dlangui/core/i18n.d

@@ -40,6 +40,7 @@ Authors:   $(WEB coolreader.org, Vadim Lopatin)
 */
 module dlangui.core.i18n;
 
+import dlangui.core.types;
 import dlangui.core.logger;
 import std.utf;
 
@@ -108,6 +109,18 @@ class UIStringTranslator {
     @property string resourceDir() { return _resourceDir; }
     /// set i18n resource directory
     @property void resourceDir(string dir) { _resourceDir = dir; }
+    /// looks for i18n directory inside one of passed dirs, and uses first found as directory to read i18n files from
+    string findTranslationsDir(string[] dirs ...) {
+        import std.file;
+        foreach(dir; dirs) {
+            string path = appendPath(dir, "i18n/");
+            if (exists(path) && isDir(path)) {
+                _resourceDir = path;
+                return _resourceDir;
+            }
+        }
+        return null;
+    }
 
     /// convert resource path - зкуpend resource dir if necessary
     string convertResourcePath(string filename) {

src/dlangui/core/types.d

@@ -286,3 +286,68 @@ enum State : uint {
     Parent = 0x10000, // use parent's state
 }
 
+
+
+version (Windows) {
+    immutable char PATH_DELIMITER = '\\';
+} else {
+    immutable char PATH_DELIMITER = '/';
+}
+
+/// returns true if char ch is / or \ slash
+bool isPathDelimiter(char ch) {
+    return ch == '/' || ch == '\\';
+}
+
+/// returns current executable path only, including last path delimiter
+@property string exePath() {
+    import std.file;
+    string path = thisExePath();
+    int lastSlash = 0;
+    for (int i = 0; i < path.length; i++)
+        if (path[i] == PATH_DELIMITER)
+            lastSlash = i;
+    return path[0 .. lastSlash + 1];
+}
+
+/// converts path delimiters to standard for platform inplace in buffer(e.g. / to \ on windows, \ to / on posix), returns buf
+char[] convertPathDelimiters(char[] buf) {
+    foreach(ref ch; buf) {
+        version (Windows) {
+            if (ch == '/')
+                ch = '\\';
+        } else {
+            if (ch == '\\')
+                ch = '/';
+        }
+    }
+    return buf;
+}
+
+/// converts path delimiters to standard for platform (e.g. / to \ on windows, \ to / on posix)
+string convertPathDelimiters(string src) {
+    char[] buf = src.dup;
+    return cast(string)convertPathDelimiters(buf);
+}
+
+/// appends file path parts with proper delimiters e.g. appendPath("/home/user", ".myapp", "config") => "/home/user/.myapp/config"
+string appendPath(string[] pathItems ...) {
+    char[] buf;
+    foreach (s; pathItems) {
+        if (buf.length && !isPathDelimiter(buf[$-1]))
+            buf ~= PATH_DELIMITER;
+        buf ~= s;
+    }
+    return convertPathDelimiters(buf).dup;
+}
+
+/// appends file path parts with proper delimiters (as well converts delimiters inside path to system) to buffer e.g. appendPath("/home/user", ".myapp", "config") => "/home/user/.myapp/config"
+char[] appendPath(char[] buf, string[] pathItems ...) {
+    foreach (s; pathItems) {
+        if (buf.length && !isPathDelimiter(buf[$-1]))
+            buf ~= PATH_DELIMITER;
+        buf ~= s;
+    }
+    return convertPathDelimiters(buf);
+}
+

src/dlangui/graphics/resources.d

@@ -701,8 +701,22 @@ class DrawableCache {
     @property string[] resourcePaths() {
         return _resourcePaths;
     }
+    /// set resource directory paths as variable number of parameters
+    void setResourcePaths(string[] paths ...) {
+        resourcePaths(paths);
+    }
+    /// set resource directory paths array (only existing dirs will be added)
     @property void resourcePaths(string[] paths) {
-        _resourcePaths = paths;
+        string[] existingPaths;
+        foreach(path; paths) {
+            if (exists(path) && isDir(path)) {
+                existingPaths ~= path;
+                Log.d("DrawableCache: adding path ", path, " to resource dir list.");
+            } else {
+                Log.d("DrawableCache: path ", path, " does not exist.");
+            }
+        }
+        _resourcePaths = existingPaths;
         clear();
     }
     /// concatenates path with resource id and extension, returns pathname if there is such file, null if file does not exist

src/dlangui/platforms/common/platform.d

@@ -491,19 +491,29 @@ version (USE_OPENGL) {
     }
 }
 
-version (Windows) {
-    immutable char PATH_DELIMITER = '\\';
-} else {
-    immutable char PATH_DELIMITER = '/';
-}
 
-/// returns current executable path only, including last path delimiter
-string exePath() {
-    import std.file;
-    string path = thisExePath();
-    int lastSlash = 0;
-    for (int i = 0; i < path.length; i++)
-        if (path[i] == PATH_DELIMITER)
-            lastSlash = i;
-    return path[0 .. lastSlash + 1];
+/// put "mixin APP_ENTRY_POINT;" to main module of your dlangui based app
+mixin template APP_ENTRY_POINT() {
+    version (linux) {
+	    //pragma(lib, "png");
+	    pragma(lib, "xcb");
+	    pragma(lib, "xcb-shm");
+	    pragma(lib, "xcb-image");
+	    pragma(lib, "X11-xcb");
+	    pragma(lib, "X11");
+	    pragma(lib, "dl");
+    }
+
+    /// workaround for link issue when WinMain is located in library
+    version(Windows) {
+        private import win32.windows;
+        private import dlangui.platforms.windows.winapp;
+        extern (Windows)
+            int WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
+                        LPSTR lpCmdLine, int nCmdShow)
+            {
+                return DLANGUIWinMain(hInstance, hPrevInstance,
+                                      lpCmdLine, nCmdShow);
+            }
+    }
 }