From 1ac25358b84482661c449eb0cc532023516339ce Mon Sep 17 00:00:00 2001
From: tibbi <tibor@kaputa.sk>
Date: Mon, 2 Sep 2019 20:58:07 +0200
Subject: [PATCH] add an initial check related to exiting the app with unsaved
 changes

---
 .../simplemobiletools/draw/pro/activities/MainActivity.kt  | 7 +++++++
 .../com/simplemobiletools/draw/pro/views/MyCanvas.kt       | 2 ++
 2 files changed, 9 insertions(+)

diff --git a/app/src/main/kotlin/com/simplemobiletools/draw/pro/activities/MainActivity.kt b/app/src/main/kotlin/com/simplemobiletools/draw/pro/activities/MainActivity.kt
index b410a2c..3f6a667 100644
--- a/app/src/main/kotlin/com/simplemobiletools/draw/pro/activities/MainActivity.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/draw/pro/activities/MainActivity.kt
@@ -51,6 +51,7 @@ class MainActivity : SimpleActivity(), CanvasListener {
     private var uriToLoad: Uri? = null
     private var color = 0
     private var brushSize = 0f
+    private var savedPathsHash = 0L
     private var isEraserOn = false
     private var isImageCaptureIntent = false
     private var isEditIntent = false
@@ -140,6 +141,11 @@ class MainActivity : SimpleActivity(), CanvasListener {
         return true
     }
 
+    override fun onBackPressed() {
+        val hasUnsavedChanges = savedPathsHash != my_canvas.getDrawingHashCode()
+        super.onBackPressed()
+    }
+
     private fun launchSettings() {
         startActivity(Intent(applicationContext, SettingsActivity::class.java))
     }
@@ -344,6 +350,7 @@ class MainActivity : SimpleActivity(), CanvasListener {
 
     private fun saveImage() {
         SaveImageDialog(this, defaultExtension, defaultPath, defaultFilename) {
+            savedPathsHash = my_canvas.getDrawingHashCode()
             saveFile(it)
             defaultPath = it.getParentPath()
             defaultFilename = it.getFilenameFromPath()
diff --git a/app/src/main/kotlin/com/simplemobiletools/draw/pro/views/MyCanvas.kt b/app/src/main/kotlin/com/simplemobiletools/draw/pro/views/MyCanvas.kt
index 7be43a7..9ba9e25 100644
--- a/app/src/main/kotlin/com/simplemobiletools/draw/pro/views/MyCanvas.kt
+++ b/app/src/main/kotlin/com/simplemobiletools/draw/pro/views/MyCanvas.kt
@@ -248,6 +248,8 @@ class MyCanvas(context: Context, attrs: AttributeSet) : View(context, attrs) {
         mListener?.toggleUndoVisibility(mPaths.isNotEmpty() || mLastPaths.isNotEmpty())
     }
 
+    fun getDrawingHashCode() = mPaths.hashCode().toLong() + (mBackgroundBitmap?.hashCode()?.toLong() ?: 0L)
+
     override fun onTouchEvent(event: MotionEvent): Boolean {
         if (mAllowZooming) {
             mScaleDetector!!.onTouchEvent(event)