diff --git a/app/src/main/java/com/ray650128/floatingwindow/DensityExtension.kt b/app/src/main/java/com/ray650128/floatingwindow/DensityExtension.kt
new file mode 100644
index 0000000..6fdc956
--- /dev/null
+++ b/app/src/main/java/com/ray650128/floatingwindow/DensityExtension.kt
@@ -0,0 +1,9 @@
+package com.ray650128.floatingwindow
+
+import android.content.res.Resources
+
+val Int.dp: Int
+    get() = (this * Resources.getSystem().displayMetrics.density).toInt()
+
+val Int.px: Int
+    get() = (this / Resources.getSystem().displayMetrics.density).toInt()
\ No newline at end of file
diff --git a/app/src/main/java/com/ray650128/floatingwindow/utils/DensityUtil.kt b/app/src/main/java/com/ray650128/floatingwindow/utils/DensityUtil.kt
new file mode 100644
index 0000000..70a7117
--- /dev/null
+++ b/app/src/main/java/com/ray650128/floatingwindow/utils/DensityUtil.kt
@@ -0,0 +1,77 @@
+package com.ray650128.floatingwindow.utils
+
+import android.content.Context
+import android.os.Build
+import android.util.DisplayMetrics
+import android.view.WindowManager
+import com.ray650128.floatingwindow.MyApp
+
+
+/**
+ * 畫面尺寸相關工具類別。
+ */
+object DensityUtil {
+
+    /**
+     * 取得螢幕寬度
+     * @return 螢幕寬度(px)
+     */
+    fun getScreenWidth(): Int {
+        val windowManager = MyApp.appContext.getSystemService(Context.WINDOW_SERVICE) as WindowManager
+
+        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
+            val windowMetrics = windowManager.currentWindowMetrics
+            windowMetrics.bounds.width()
+        } else {
+            val metric = DisplayMetrics()
+            windowManager.defaultDisplay.getMetrics(metric)
+            metric.widthPixels
+        }
+    }
+
+    /**
+     * 取得螢幕高度
+     * @return 螢幕高度(px)
+     */
+    fun getScreenHeight(): Int {
+        val windowManager = MyApp.appContext.getSystemService(Context.WINDOW_SERVICE) as WindowManager
+
+        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.R) {
+            val windowMetrics = windowManager.currentWindowMetrics
+            windowMetrics.bounds.height()
+        } else {
+            val metric = DisplayMetrics()
+            windowManager.defaultDisplay.getMetrics(metric)
+            metric.heightPixels
+        }
+    }
+
+    /**
+     * 取得狀態列高度
+     * @return 狀態列高度(px)
+     */
+    fun getStatusBarHeight(): Int {
+        var result = 0
+        val resourceId: Int = MyApp.appContext.resources.getIdentifier(
+            "status_bar_height",
+            "dimen",
+            "android"
+        )
+        if (resourceId > 0) {
+            result = MyApp.appContext.resources.getDimensionPixelSize(resourceId)
+        }
+        return result
+    }
+
+    /**
+     * 取得導航列高度
+     * @return 導航列高度(px)
+     */
+    fun getNavigationBarHeight(): Int {
+        val resources = MyApp.appContext.resources
+        val resourceId: Int = resources.getIdentifier("navigation_bar_height", "dimen", "android")
+        return if (resourceId > 0) {
+            resources.getDimensionPixelSize(resourceId)
+        } else 0
+    }
+}
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