Made the TagEditor more reliable.

app/src/main/java/com/kabouzeid/gramophone/misc/DialogAsyncTask.java

@@ -0,0 +1,104 @@
+package com.kabouzeid.gramophone.misc;
+
+import android.app.Dialog;
+import android.content.Context;
+import android.os.AsyncTask;
+import android.os.Handler;
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * @author Karim Abou Zeid (kabouzeid)
+ */
+public abstract class DialogAsyncTask<Params, Progress, Result> extends AsyncTask<Params, Progress, Result> {
+    private final int delay;
+    private WeakReference<Context> contextWeakReference;
+    private WeakReference<Dialog> dialogWeakReference;
+
+    private boolean supposedToBeDismissed;
+
+    public DialogAsyncTask(Context context) {
+        this(context, 0);
+    }
+
+    public DialogAsyncTask(Context context, int showDelay) {
+        this.delay = showDelay;
+        contextWeakReference = new WeakReference<>(context);
+        dialogWeakReference = new WeakReference<>(null);
+    }
+
+    @Override
+    protected void onPreExecute() {
+        super.onPreExecute();
+        if (delay > 0) {
+            new Handler().postDelayed(new Runnable() {
+                @Override
+                public void run() {
+                    initAndShowDialog();
+                }
+            }, delay);
+        } else {
+            initAndShowDialog();
+        }
+    }
+
+    private void initAndShowDialog() {
+        Context context = getContext();
+        if (!supposedToBeDismissed && context != null) {
+            Dialog dialog = createDialog(context);
+            dialogWeakReference = new WeakReference<>(dialog);
+            dialog.show();
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    protected void onProgressUpdate(Progress... values) {
+        super.onProgressUpdate(values);
+        Dialog dialog = getDialog();
+        if (dialog != null) {
+            onProgressUpdate(dialog, values);
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    protected void onProgressUpdate(@NonNull Dialog dialog, Progress... values) {
+    }
+
+    @Nullable
+    protected Context getContext() {
+        return contextWeakReference.get();
+    }
+
+    @Nullable
+    protected Dialog getDialog() {
+        return dialogWeakReference.get();
+    }
+
+    @Override
+    protected void onCancelled(Result result) {
+        super.onCancelled(result);
+        tryToDismiss();
+    }
+
+    @Override
+    protected void onPostExecute(Result result) {
+        super.onPostExecute(result);
+        tryToDismiss();
+    }
+
+    private void tryToDismiss() {
+        supposedToBeDismissed = true;
+        try {
+            Dialog dialog = getDialog();
+            if (dialog != null)
+                dialog.dismiss();
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
+    protected abstract Dialog createDialog(@NonNull Context context);
+}

app/src/main/java/com/kabouzeid/gramophone/misc/UpdateToastMediaScannerCompletionListener.java

@@ -0,0 +1,59 @@
+package com.kabouzeid.gramophone.misc;
+
+import android.annotation.SuppressLint;
+import android.app.Activity;
+import android.media.MediaScannerConnection;
+import android.net.Uri;
+import android.widget.Toast;
+
+import com.kabouzeid.gramophone.R;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * @author Karim Abou Zeid (kabouzeid)
+ */
+public class UpdateToastMediaScannerCompletionListener implements MediaScannerConnection.OnScanCompletedListener {
+    int scanned = 0;
+    int failed = 0;
+
+    private final String[] toBeScanned;
+
+    private final String scannedFiles;
+    private final String couldNotScanFiles;
+
+    private final WeakReference<Toast> toastWeakReference;
+    private final WeakReference<Activity> activityWeakReference;
+
+    @SuppressLint("ShowToast")
+    public UpdateToastMediaScannerCompletionListener(Activity activity, String[] toBeScanned) {
+        this.toBeScanned = toBeScanned;
+        scannedFiles = activity.getString(R.string.scanned_files);
+        couldNotScanFiles = activity.getString(R.string.could_not_scan_files);
+        toastWeakReference = new WeakReference<>(Toast.makeText(activity, "", Toast.LENGTH_SHORT));
+        activityWeakReference = new WeakReference<>(activity);
+    }
+
+    @Override
+    public void onScanCompleted(final String path, final Uri uri) {
+        Activity activity = activityWeakReference.get();
+        if (activity != null) {
+            activity.runOnUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    Toast toast = toastWeakReference.get();
+                    if (toast != null) {
+                        if (uri == null) {
+                            failed++;
+                        } else {
+                            scanned++;
+                        }
+                        String text = " " + String.format(scannedFiles, scanned, toBeScanned.length) + (failed > 0 ? " " + String.format(couldNotScanFiles, failed) : "");
+                        toast.setText(text);
+                        toast.show();
+                    }
+                }
+            });
+        }
+    }
+}