Add flag to emulate mobile during preview

Since the is_mobile check was moved to compile-time instead of runtime
in 0a6a441041, we need a way to override
the check when previewing using the 'mobile' flag.

Signed-off-by: kernelkind <kernelkind@gmail.com>
Signed-off-by: William Casarin <jb55@jb55.com>

Cargo.toml

@@ -45,6 +45,7 @@ egui_virtual_list = "0.3.0"
 
 [features]
 default = []
+emulate_mobile = []
 profiling = ["puffin", "puffin_egui", "eframe/puffin"]
 
 [profile.small]

preview

@@ -1,2 +1,20 @@
 #!/usr/bin/env bash
-cargo run --bin ui_preview --release -- "$@"
+
+MOBILE_FLAG=0
+FILTERED_ARGS=()
+
+# Loop through the command line arguments
+for arg in "$@"; do
+    if [[ "$arg" == "--mobile" ]]; then
+        MOBILE_FLAG=1
+    else
+        # Add non '--mobile' arguments to the filtered list
+        FILTERED_ARGS+=("$arg")
+    fi
+done
+
+if [[ "$MOBILE_FLAG" -eq 1 ]]; then
+    cargo run --bin ui_preview --features emulate_mobile --release -- "${FILTERED_ARGS[@]}"
+else
+    cargo run --bin ui_preview --release -- "$@"
+fi

src/ui/mod.rs

@@ -38,7 +38,13 @@ pub fn padding<R>(
 }
 
 #[inline]
+#[allow(unreachable_code)]
 pub fn is_mobile(_ctx: &egui::Context) -> bool {
+    #[cfg(feature = "emulate_mobile")]
+    {
+        return true;
+    }
+
     #[cfg(any(target_os = "android", target_os = "ios"))]
     {
         true

src/ui_preview/main.rs

@@ -54,14 +54,17 @@ macro_rules! previews {
 #[tokio::main]
 async fn main() {
     let mut name: Option<String> = None;
+
+    #[allow(unused_assignments)]
+    #[allow(unused_mut)]
     let mut is_mobile = false;
+    #[cfg(feature = "emulate_mobile")]
+    {
+        is_mobile = true
+    }
 
     for arg in env::args() {
-        if arg == "--mobile" {
-            is_mobile = true;
-        } else {
-            name = Some(arg);
-        }
+        name = Some(arg);
     }
 
     let name = if let Some(name) = name {