save status display

check for URI existence before read file. Maybe this helps when content
provider is not ready onResume

app/src/main/java/org/wntr/mdeditor/MainActivity.kt

@@ -16,7 +16,6 @@ import android.provider.OpenableColumns
 import android.util.Log
 import android.view.Menu
 import android.view.MenuItem
-import android.view.Window
 import android.view.WindowInsets
 import android.view.WindowManager
 import android.webkit.ConsoleMessage
@@ -67,8 +66,8 @@ class MainActivity : AppCompatActivity() {
             {
                 className: "editor-statusbar-left",
                 onUpdate: (el) => {
-                el.innerHTML = "<i class=\"fa fa-circle\"></i>"
-            }
+                    el.innerHTML = saveStatus()
+                }    
             },
             {
                 className: "displayName",
@@ -953,7 +952,6 @@ class MainActivity : AppCompatActivity() {
             selectFileForSaveAs()
             return
         }
-
         catch (e: Exception) {
             Log.d(javaClass.simpleName, "Problem with accessing file\n${e.stackTraceToString()}")
             this.runOnUiThread(
@@ -969,8 +967,19 @@ class MainActivity : AppCompatActivity() {
         }
 
         try {
-            this. runOnUiThread({
+            this.runOnUiThread({
                 webView.evaluateJavascript("getValue();") {
+                    if (it == "") {
+                        return@evaluateJavascript
+                    } else if (it == "null") {
+                        Toast.makeText(
+                            this,
+                            "Problem with file buffer. Please reopen manually.",
+                            Toast.LENGTH_LONG
+                        ).show()
+                        openFile()
+                        return@evaluateJavascript
+                    }
                     mdeValue =
                         metaData.toString() + URLDecoder.decode(it.removeSurrounding("\""))
                     if (mdeValue.length.toLong() == textFile.statSize) {
@@ -985,7 +994,10 @@ class MainActivity : AppCompatActivity() {
                     Log.d(javaClass.simpleName, "File saved: ${thisFileUri}")
                     textFile.close()
                     this@MainActivity.runOnUiThread {
-                        webView.evaluateJavascript("easyMDE.codemirror.doc.markClean();", {})
+                        webView.evaluateJavascript(
+                            "easyMDE.codemirror.doc.markClean();" +
+                                   "easyMDE.updateStatusBar(\"editor-statusbar-left\",saveStatus());"
+                            , {})
                     }
                 }
             })
@@ -1037,6 +1049,13 @@ class MainActivity : AppCompatActivity() {
         }
     }
 
+    fun checkURIResource(context: Context, uri: Uri?): Boolean {
+        val cursor = context.contentResolver.query(uri!!, null, null, null, null)
+        val doesExist = cursor != null && cursor.moveToFirst()
+        cursor?.close()
+        return doesExist
+    }
+
     @Throws(IOException::class)
     private fun readFile(uri: Uri) {
         //TODO: Which permissions are really needed?
@@ -1068,6 +1087,19 @@ class MainActivity : AppCompatActivity() {
         CoroutineScope(Dispatchers.Main).launch {
             withContext(Dispatchers.IO) {
                 try {
+                    if (!checkURIResource(applicationContext, uri)) {
+                        Log.d(javaClass.simpleName, "URI unavailable")
+                        this@MainActivity.runOnUiThread({
+                            Toast.makeText(
+                                this@MainActivity,
+                                "URI check failed\n" +
+                                        "Better open from another storage location\n" ,
+                                Toast.LENGTH_LONG
+                            ).show()
+                        })
+                        thisFileUri = null
+                        return@withContext
+                    }
                     contentResolver.openInputStream(uri)?.use { inputStream ->
                         BufferedReader(InputStreamReader(inputStream)).use { reader ->
                             var i = ""
@@ -1096,8 +1128,10 @@ class MainActivity : AppCompatActivity() {
                     this@MainActivity.runOnUiThread({
                         Toast.makeText(
                             this@MainActivity,
-                            "File not found during reading.\n$e",
-                            Toast.LENGTH_LONG
+                            "File not found during reading.\n" +
+                                 "Current Buffer is not connected to any file now.\n" +
+                                 "Save with other file name or open another.",
+                                    Toast.LENGTH_LONG
                         ).show()
                     })
                     thisFileUri = null
@@ -1136,6 +1170,7 @@ class MainActivity : AppCompatActivity() {
                     val script = "if (typeof easyMDE !== 'undefined') {" +
                                  "easyMDE.codemirror.doc.setValue(`${mdeValue}`);" +
                                  "easyMDE.codemirror.doc.markClean();" +
+                                 "easyMDE.updateStatusBar(\"editor-statusbar-left\",saveStatus());" +
                                  "easyMDE.codemirror.focus();" +
                                  "easyMDE.codemirror.doc.setCursor(JSON.parse(`${metaData.cursor}`));" +
                                  "pasteText();" +
@@ -1145,7 +1180,6 @@ class MainActivity : AppCompatActivity() {
                     webView.evaluateJavascript(script, {
                         thisFileUri = uri
                         Log.d(javaClass.simpleName,"File read: ${thisFileUri}")
-                        saveFile()
                     })
                     webView.requestFocus()
                 })
@@ -1154,6 +1188,7 @@ class MainActivity : AppCompatActivity() {
     }
 
     private fun saveMetaToSharedPrefs() {
+        if (thisFileUri == null) return
         Log.d(javaClass.simpleName, "saving to shared prefs cursor: ${metaData.cursor} in file: ${thisFileUri}")
         getSharedPreferences("prefs", Context.MODE_PRIVATE)
             .edit().apply {
@@ -1186,7 +1221,6 @@ class MainActivity : AppCompatActivity() {
 
     override fun onPause() {
         super.onPause()
-        /*outState.putString("test", "onSaveInstanceState-String")*/
         saveFile()
         webView.evaluateJavascript("easyMDE.codemirror.doc.getCursor();") {
             metaData.cursor=it
@@ -1198,11 +1232,6 @@ class MainActivity : AppCompatActivity() {
 
     override protected fun onRestoreInstanceState(savedInstanceState: Bundle) {
         super.onRestoreInstanceState(savedInstanceState)
-        /*        findViewById<TextView>(R.id.edittext_lifecycle).text = savedInstanceState.getString("test")*/
-        /*webView.evaluateJavascript("getValue();", ValueCallback<String>() {
-            saveFile(it)
-        })*/
-
         Log.i(javaClass.simpleName, "\"onRestoreInstanceState\" durchlaufen")
     }
 }

app/src/main/java/org/wntr/mdeditor/mdMeta.kt

@@ -12,7 +12,9 @@ class mdMeta {
     var ID: String? = null
     var updatedAt: String? = null
     var cursor: String =  "{ line: 0, ch: 0, sticky: null }"
-
+        get() =
+            if (field.equals("null"))  "{ line: 0, ch: 0, sticky: null }"
+            else field
 
     fun put(key: String, value: String) {
         metaData.put(key, value)

app/src/main/res/raw/controller.js

@@ -75,3 +75,9 @@ function toggleTheme() {
     if (i>themes.length-1) i=0
 }
 
+function saveStatus() {
+    if (typeof easyMDE === 'undefined') return ''
+    else if (easyMDE.codemirror.doc.isClean()) return '*'
+    return ''
+}
+