diff --git a/src/main.c b/src/main.c
index 7c3ebe9..adf41e3 100644
--- a/src/main.c
+++ b/src/main.c
@@ -24,6 +24,7 @@ static void cleanup(void);
 
 static monitor_t *monitors = NULL;
 static wallpaper_config_t *wallpaper_config = NULL;
+static GMainLoop *loop = NULL;
 
 /* 调试函数，开发完成后删除 */
 static void print_monitor_list_info(monitor_t *monitor_list) {
@@ -84,12 +85,10 @@ void init_monitors(void) {
 void init_wallpaper(void) {
   wallpaper_config = parse_wallpaper_config(wallpager_list);
   if (!wallpaper_config) return;
-  if (wallpaper_interval) {
-    g_timeout_add_seconds(wallpaper_interval, update_wallpaper,
-                          wallpaper_config);
-  }
 
   update_wallpaper(wallpaper_config);
+  if (!wallpaper_interval) return;
+  g_timeout_add_seconds(wallpaper_interval, update_wallpaper, wallpaper_config);
 }
 
 gboolean update_wallpaper(gpointer user_data) {
@@ -100,6 +99,10 @@ gboolean update_wallpaper(gpointer user_data) {
   set_wallpaper_by_index(index);
   uint32_t monitor_count = 0;
   for (monitor_t *m = monitors; m; m = m->next) monitor_count++;
+
+  /* 屏幕比壁纸多则不动态切换 */
+  if (!monitor_count || monitor_count >= wc->count) return false;
+
   if (monitor_count) {
     index += monitor_count;
     index %= wc->count;
@@ -114,10 +117,13 @@ void set_wallpaper_by_index(uint32_t index) {
   rect_size_t *screen_size = get_screen_size();
   uint32_t *wallpaper = generate_wallpaper(
     wallpaper_config, monitors, index, screen_size->width, screen_size->height);
-  set_wallpaper(wallpaper);
+
+  if (wallpaper) {
+    set_wallpaper(wallpaper);
+    free(wallpaper);
+  }
 
   free(screen_size);
-  free(wallpaper);
 }
 
 wallpaper_config_t *parse_wallpaper_config(const char **wallpapers) {
@@ -194,7 +200,7 @@ int main(int argc, char *argv[]) {
 
   free_window_list(window_list);
 
-  GMainLoop *loop = g_main_loop_new(NULL, FALSE);
+  loop = g_main_loop_new(NULL, FALSE);
   g_main_loop_run(loop);
 
   cleanup();