[FIX] fix issue directory chooser mode

[ADD] add infos for directory chooser, and detail view mode in readme.md

Author: aiekick

ImGuiFileDialog/ImGuiFileDialog.cpp

@@ -1271,16 +1271,19 @@ namespace igfd
 		bool found = false;
 		int itemIdx = 0;
 		const char* p = dlg_filters;
-		while (*p)
+		if (p)
 		{
-			if (m_SelectedExt == std::string(p))
+			while (*p)
 			{
-				found = true;
-				FilterIndex = itemIdx;
-				break;
+				if (m_SelectedExt == std::string(p))
+				{
+					found = true;
+					FilterIndex = itemIdx;
+					break;
+				}
+				p += strlen(p) + 1;
+				itemIdx++;
 			}
-			p += strlen(p) + 1;
-			itemIdx++;
 		}
 		if (!found)
 		{

README.md

@@ -158,7 +158,16 @@ ImVec2 minSize = maxSize * 0.5f;
 igfd::ImGuiFileDialog::Instance()->FileDialog("ChooseFileDlgKey", ImGuiWindowFlags_NoCollapse, minSize, maxSize);
 ```
 
-![alt text](doc/contraintDisplay.gif)
+![alt text](doc/dialog_constraints.gif)
+
+## Detail View Mode
+
+You can have tables display like that.
+
+- you need to use imgui tables branch (not merged in master at this moment)
+- uncomment "#define USE_IMGUI_TABLES" in you custom config file (CustomImGuiFileDialogConfig.h in this example)
+
+![alt text](doc/imgui_tables_branch.gif)
 
 ## Using ImGuiFileDialog as a module