Improving lazing loading. The scrollbars updates itself

src/assets/main.js

@@ -25,11 +25,19 @@ function bindTooltipsWithDelegation() {
 
     // Add a single mouseenter and mouseleave listener to the parent element
     element.addEventListener("mouseenter", (event) => {
+        //console.debug("Entering element", event.target)
+
         const cell = event.target.closest("[data-tooltip]");
-        if (!cell) return;
+        if (!cell) {
+          // console.debug("  No 'data-tooltip' attribute found. Stopping.");
+          return;
+        }
 
         const no_tooltip = element.hasAttribute("mmt-no-tooltip");
-        if (no_tooltip) return;
+        if (no_tooltip) {
+          // console.debug("  Attribute 'mmt-no-tooltip' found. Cancelling.");
+          return;
+        }
 
         const content = cell.querySelector(".truncate") || cell;
         const isOverflowing = content.scrollWidth > content.clientWidth;

src/components/datagrid_new/assets/Datagrid.js

@@ -1,10 +1,6 @@
 function bindDatagrid(datagridId, allowColumnsReordering) {
-    bindScrollbars(datagridId);
+    manageScrollbars(datagridId, true);
-    makeResizable(datagridId)
+    makeResizable(datagridId);
-
-    document.body.addEventListener('htmx:sseBeforeMessage', function (e) {
-        console.log("htmx:sseBeforeMessage", e)
-    })
 }
 
 function bindScrollbars(datagridId) {
@@ -180,6 +176,224 @@ function bindScrollbars(datagridId) {
     });
 }
 
+function manageScrollbars(datagridId, binding) {
+    console.debug("manageScrollbars on element " + datagridId + " with binding=" + binding);
+
+    const datagrid = document.getElementById(datagridId);
+
+    if (!datagrid) {
+        console.error(`Datagrid with id "${datagridId}" not found.`);
+        return;
+    }
+
+    const verticalScrollbar = datagrid.querySelector(".dt2-scrollbars-vertical");
+    const verticalWrapper = datagrid.querySelector(".dt2-scrollbars-vertical-wrapper");
+    const horizontalScrollbar = datagrid.querySelector(".dt2-scrollbars-horizontal");
+    const horizontalWrapper = datagrid.querySelector(".dt2-scrollbars-horizontal-wrapper");
+    const body = datagrid.querySelector(".dt2-body");
+    const table = datagrid.querySelector(".dt2-table");
+
+    if (!verticalScrollbar || !verticalWrapper || !horizontalScrollbar || !horizontalWrapper || !body || !table) {
+        console.error("Essential scrollbars or content elements are missing in the datagrid.");
+        return;
+    }
+
+    const computeScrollbarVisibility = () => {
+        // Determine if the content is clipped
+        const isVerticalRequired = body.scrollHeight > body.clientHeight;
+        const isHorizontalRequired = table.scrollWidth > table.clientWidth;
+
+        // Show or hide the scrollbar wrappers
+        requestAnimationFrame(() => {
+            verticalWrapper.style.display = isVerticalRequired ? "block" : "none";
+            horizontalWrapper.style.display = isHorizontalRequired ? "block" : "none";
+        });
+    };
+
+    const computeScrollbarSize = () => {
+        // Vertical scrollbar height
+        const visibleHeight = body.clientHeight;
+        const totalHeight = body.scrollHeight;
+        const wrapperHeight = verticalWrapper.offsetHeight;
+
+        let scrollbarHeight = 0;
+        if (totalHeight > 0) {
+            scrollbarHeight = (visibleHeight / totalHeight) * wrapperHeight;
+        }
+
+        // Horizontal scrollbar width
+        const visibleWidth = table.clientWidth;
+        const totalWidth = table.scrollWidth;
+        const wrapperWidth = horizontalWrapper.offsetWidth;
+
+        let scrollbarWidth = 0;
+        if (totalWidth > 0) {
+            scrollbarWidth = (visibleWidth / totalWidth) * wrapperWidth;
+        }
+
+        requestAnimationFrame(() => {
+            verticalScrollbar.style.height = `${scrollbarHeight}px`;
+            horizontalScrollbar.style.width = `${scrollbarWidth}px`;
+        });
+    };
+
+    const updateVerticalScrollbarForMouseWheel = () => {
+        const maxScrollTop = body.scrollHeight - body.clientHeight;
+        const wrapperHeight = verticalWrapper.offsetHeight;
+
+        if (maxScrollTop > 0) {
+            const scrollRatio = wrapperHeight / body.scrollHeight;
+            verticalScrollbar.style.top = `${body.scrollTop * scrollRatio}px`;
+        }
+    };
+
+    if (binding) {
+        // Clean up existing managers if they exist
+        if (datagrid._managers) {
+            // Remove drag events
+            if (datagrid._managers.dragManager) {
+                verticalScrollbar.removeEventListener("mousedown", datagrid._managers.dragManager.verticalMouseDown);
+                horizontalScrollbar.removeEventListener("mousedown", datagrid._managers.dragManager.horizontalMouseDown);
+                document.removeEventListener("mousemove", datagrid._managers.dragManager.mouseMove);
+                document.removeEventListener("mouseup", datagrid._managers.dragManager.mouseUp);
+            }
+
+            // Remove wheel events
+            if (datagrid._managers.wheelManager) {
+                body.removeEventListener("wheel", datagrid._managers.wheelManager.handleWheelScrolling);
+            }
+
+            // Remove resize events
+            if (datagrid._managers.resizeManager) {
+                window.removeEventListener("resize", datagrid._managers.resizeManager.handleResize);
+            }
+        }
+
+        // Create managers
+        const dragManager = {
+            isDragging: false,
+            startY: 0,
+            startX: 0,
+
+            updateVerticalScrollbar: (deltaX, deltaY) => {
+                const wrapperHeight = verticalWrapper.offsetHeight;
+                const scrollbarHeight = verticalScrollbar.offsetHeight;
+                const maxScrollTop = body.scrollHeight - body.clientHeight;
+                const scrollRatio = maxScrollTop / (wrapperHeight - scrollbarHeight);
+
+                let newTop = parseFloat(verticalScrollbar.style.top || "0") + deltaY;
+                newTop = Math.max(0, Math.min(newTop, wrapperHeight - scrollbarHeight));
+
+                verticalScrollbar.style.top = `${newTop}px`;
+                body.scrollTop = newTop * scrollRatio;
+            },
+
+            updateHorizontalScrollbar: (deltaX, deltaY) => {
+                const wrapperWidth = horizontalWrapper.offsetWidth;
+                const scrollbarWidth = horizontalScrollbar.offsetWidth;
+                const maxScrollLeft = table.scrollWidth - table.clientWidth;
+                const scrollRatio = maxScrollLeft / (wrapperWidth - scrollbarWidth);
+
+                let newLeft = parseFloat(horizontalScrollbar.style.left || "0") + deltaX;
+                newLeft = Math.max(0, Math.min(newLeft, wrapperWidth - scrollbarWidth));
+
+                horizontalScrollbar.style.left = `${newLeft}px`;
+                table.scrollLeft = newLeft * scrollRatio;
+            },
+
+            verticalMouseDown: (e) => {
+                disableTooltip();
+                dragManager.isDragging = true;
+                dragManager.startY = e.clientY;
+                dragManager.startX = e.clientX;
+                document.body.style.userSelect = "none";
+                verticalScrollbar.classList.add("dt2-dragging");
+            },
+
+            horizontalMouseDown: (e) => {
+                disableTooltip();
+                dragManager.isDragging = true;
+                dragManager.startY = e.clientY;
+                dragManager.startX = e.clientX;
+                document.body.style.userSelect = "none";
+                horizontalScrollbar.classList.add("dt2-dragging");
+            },
+
+            mouseMove: (e) => {
+                if (dragManager.isDragging) {
+                    const deltaY = e.clientY - dragManager.startY;
+                    const deltaX = e.clientX - dragManager.startX;
+
+                    // Determine which scrollbar is being dragged
+                    if (verticalScrollbar.classList.contains("dt2-dragging")) {
+                        dragManager.updateVerticalScrollbar(deltaX, deltaY);
+                    } else if (horizontalScrollbar.classList.contains("dt2-dragging")) {
+                        dragManager.updateHorizontalScrollbar(deltaX, deltaY);
+                    }
+
+                    // Reset start points for next update
+                    dragManager.startY = e.clientY;
+                    dragManager.startX = e.clientX;
+                }
+            },
+
+            mouseUp: () => {
+                dragManager.isDragging = false;
+                document.body.style.userSelect = "";
+                verticalScrollbar.classList.remove("dt2-dragging");
+                horizontalScrollbar.classList.remove("dt2-dragging");
+                enableTooltip();
+            }
+        };
+
+        const wheelManager = {
+            handleWheelScrolling: (event) => {
+                const deltaX = event.deltaX;
+                const deltaY = event.deltaY;
+
+                // Scroll the body and table content
+                body.scrollTop += deltaY; // Vertical scrolling
+                table.scrollLeft += deltaX; // Horizontal scrolling
+
+                // Update the vertical scrollbar position
+                updateVerticalScrollbarForMouseWheel();
+
+                // Prevent default behavior to fully manage the scroll
+                event.preventDefault();
+            }
+        };
+
+        const resizeManager = {
+            handleResize: () => {
+                computeScrollbarVisibility();
+                computeScrollbarSize();
+                updateVerticalScrollbarForMouseWheel();
+            }
+        };
+
+        // Store managers on datagrid for cleanup
+        datagrid._managers = {
+            dragManager,
+            wheelManager,
+            resizeManager
+        };
+
+        // Bind events
+        verticalScrollbar.addEventListener("mousedown", dragManager.verticalMouseDown);
+        horizontalScrollbar.addEventListener("mousedown", dragManager.horizontalMouseDown);
+        document.addEventListener("mousemove", dragManager.mouseMove);
+        document.addEventListener("mouseup", dragManager.mouseUp);
+
+        body.addEventListener("wheel", wheelManager.handleWheelScrolling, {passive: false});
+
+        window.addEventListener("resize", resizeManager.handleResize);
+    }
+
+    // Always execute computations
+    computeScrollbarVisibility();
+    computeScrollbarSize();
+}
+
 function makeResizable(datagridId) {
     console.debug("makeResizable on element " + datagridId);
 

src/components/datagrid_new/components/DataGrid.py

@@ -446,8 +446,8 @@ class DataGrid(BaseComponent):
       _mk_keyboard_management(),
       Div(
         self.mk_table_header(),
-        # self.mk_table_body(),
+        #self.mk_table_body(),
-        # self.mk_table_body_sse(),
+        #self.mk_table_body_sse(),
         self.mk_table_body_page(),
         self.mk_table_footer(),
         cls="dt2-inner-table"),
@@ -490,7 +490,12 @@ class DataGrid(BaseComponent):
     )
   
   def mk_table_body_sse(self):
-    
+    """
+    This function is used to create a sse update
+    Unfortunately, the sse does not update the correct element
+    tb_{self._id} is not updated
+    Plus UI refreshment issues
+    """
     max_height = self._compute_body_max_height()
     
     return Div(
@@ -505,7 +510,10 @@ class DataGrid(BaseComponent):
     )
   
   def mk_table_body_page(self):
-    
+    """
+    This function is used to update the table body when the vertical scrollbar reaches the end
+    A new page is added when requested
+    """
     max_height = self._compute_body_max_height()
     
     return Div(
@@ -552,13 +560,17 @@ class DataGrid(BaseComponent):
     else:
       last_row = None
     
-    return [Div(
+    rows =  [Div(
       *[self.mk_body_cell(col_pos, row_index, col_def) for col_pos, col_def in enumerate(self._state.columns)],
       cls="dt2-row",
       data_row=f"{row_index}",
       id=f"tr_{self._id}-{row_index}",
       **self.commands.get_page(page_index + 1) if row_index == last_row else {}
     ) for row_index in df.index[start:end]]
+    
+    rows.append(Script(f"manageScrollbars('{self._id}', false);"),)
+    
+    return rows
   
   async def mk_body_content_sse(self):
     df = self._get_filtered_df()

src/components/datagrid_new/components/commands.py

@@ -100,9 +100,10 @@ class DataGridCommandManager(BaseCommandManager):
   def get_page(self, page_index=0):
     return {
         "hx-get": f"{ROUTE_ROOT}{Routes.GetPage}",
-        "hx-swap": "afterend",
+        "hx-target": f"#tb_{self._id}",
-        "hx-vals": f'{{"_id": "{self._id}", "page": "{page_index}"}}',
+        "hx-swap": "beforeend",
-        "hx-trigger": "intersect once",
+        "hx-vals": f'{{"_id": "{self._id}", "page_index": "{page_index}"}}',
+        "hx-trigger": f"intersect root:#tb_{self._id} once",
     }
   
   def _get_hide_show_columns_attrs(self, mode, col_defs: list, new_value, cls=""):

src/core/fasthtml_helper.py

@@ -7,6 +7,9 @@ attr_map = {
     "_id": "id",
 }
 
+def safe_attr(attr_name):
+  attr_name = attr_name.replace("hx_", "hx-")
+  return attr_map.get(attr_name, attr_name)
 
 def to_html(item):
   if item is None:
@@ -31,7 +34,7 @@ class MyFt:
   
   def to_html(self):
     body_items = [to_html(item) for item in self.children]
-    return f"<{self.name} {' '.join(f'{attr_map.get(k, k)}="{v}"' for k, v in self.attrs.items())}>{' '.join(body_items)}</div>"
+    return f"<{self.name} {' '.join(f'{safe_attr(k)}="{v}"' for k, v in self.attrs.items())}>{' '.join(body_items)}</div>"
   
   def __ft__(self):
     return NotStr(self.to_html())