Android: Add the ability to delete cheats

Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/features/cheats/model/CheatsViewModel.java

@@ -20,6 +20,7 @@ public class CheatsViewModel extends ViewModel
 
   private final MutableLiveData<Integer> mCheatAddedEvent = new MutableLiveData<>(null);
   private final MutableLiveData<Integer> mCheatChangedEvent = new MutableLiveData<>(null);
+  private final MutableLiveData<Integer> mCheatDeletedEvent = new MutableLiveData<>(null);
   private final MutableLiveData<Boolean> mOpenDetailsViewEvent = new MutableLiveData<>(false);
 
   private ArrayList<PatchCheat> mPatchCheats;
@@ -200,6 +201,41 @@ public class CheatsViewModel extends ViewModel
     mCheatChangedEvent.setValue(null);
   }
 
+  /**
+   * When a cheat is deleted, the integer stored in the returned LiveData
+   * changes to the position of that cheat, then changes back to null.
+   */
+  public LiveData<Integer> getCheatDeletedEvent()
+  {
+    return mCheatDeletedEvent;
+  }
+
+  public void deleteSelectedCheat()
+  {
+    Cheat cheat = mSelectedCheat.getValue();
+    int position = mSelectedCheatPosition;
+
+    setSelectedCheat(null, -1);
+
+    if (mPatchCheats.remove(cheat))
+      mPatchCheatsNeedSaving = true;
+    if (mARCheats.remove(cheat))
+      mARCheatsNeedSaving = true;
+    if (mGeckoCheats.remove(cheat))
+      mGeckoCheatsNeedSaving = true;
+
+    notifyCheatDeleted(position);
+  }
+
+  /**
+   * Notifies that the cheat at the given position has been deleted.
+   */
+  private void notifyCheatDeleted(int position)
+  {
+    mCheatDeletedEvent.setValue(position);
+    mCheatDeletedEvent.setValue(null);
+  }
+
   public LiveData<Boolean> getOpenDetailsViewEvent()
   {
     return mOpenDetailsViewEvent;

Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/features/cheats/ui/CheatDetailsFragment.java

@@ -13,6 +13,7 @@ import android.widget.TextView;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+import androidx.appcompat.app.AlertDialog;
 import androidx.fragment.app.Fragment;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.ViewModelProvider;
@@ -32,6 +33,7 @@ public class CheatDetailsFragment extends Fragment
   private TextView mLabelNotes;
   private EditText mEditNotes;
   private EditText mEditCode;
+  private Button mButtonDelete;
   private Button mButtonEdit;
   private Button mButtonCancel;
   private Button mButtonOk;
@@ -59,6 +61,7 @@ public class CheatDetailsFragment extends Fragment
     mLabelNotes = view.findViewById(R.id.label_notes);
     mEditNotes = view.findViewById(R.id.edit_notes);
     mEditCode = view.findViewById(R.id.edit_code);
+    mButtonDelete = view.findViewById(R.id.button_delete);
     mButtonEdit = view.findViewById(R.id.button_edit);
     mButtonCancel = view.findViewById(R.id.button_cancel);
     mButtonOk = view.findViewById(R.id.button_ok);
@@ -69,6 +72,7 @@ public class CheatDetailsFragment extends Fragment
     mViewModel.getSelectedCheat().observe(getViewLifecycleOwner(), this::onSelectedCheatUpdated);
     mViewModel.getIsEditing().observe(getViewLifecycleOwner(), this::onIsEditingUpdated);
 
+    mButtonDelete.setOnClickListener(this::onDeleteClicked);
     mButtonEdit.setOnClickListener((v) -> mViewModel.setIsEditing(true));
     mButtonCancel.setOnClickListener((v) ->
     {
@@ -84,6 +88,16 @@ public class CheatDetailsFragment extends Fragment
     mEditCode.setError(null);
   }
 
+  private void onDeleteClicked(View view)
+  {
+    AlertDialog.Builder builder =
+            new AlertDialog.Builder(requireContext(), R.style.DolphinDialogBase);
+    builder.setMessage(getString(R.string.cheats_delete_confirmation, mCheat.getName()));
+    builder.setPositiveButton(R.string.yes, (dialog, i) -> mViewModel.deleteSelectedCheat());
+    builder.setNegativeButton(R.string.no, null);
+    builder.show();
+  }
+
   private void onOkClicked(View view)
   {
     clearEditErrors();
@@ -138,6 +152,7 @@ public class CheatDetailsFragment extends Fragment
     mEditNotes.setVisibility(notesVisibility);
 
     boolean userDefined = cheat != null && cheat.getUserDefined();
+    mButtonDelete.setEnabled(userDefined);
     mButtonEdit.setEnabled(userDefined);
 
     // If the fragment was recreated while editing a cheat, it's vital that we
@@ -162,6 +177,7 @@ public class CheatDetailsFragment extends Fragment
     mEditNotes.setEnabled(isEditing);
     mEditCode.setEnabled(isEditing);
 
+    mButtonDelete.setVisibility(isEditing ? View.GONE : View.VISIBLE);
     mButtonEdit.setVisibility(isEditing ? View.GONE : View.VISIBLE);
     mButtonCancel.setVisibility(isEditing ? View.VISIBLE : View.GONE);
     mButtonOk.setVisibility(isEditing ? View.VISIBLE : View.GONE);

Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/features/cheats/ui/CheatsAdapter.java

@@ -37,6 +37,12 @@ public class CheatsAdapter extends RecyclerView.Adapter<CheatItemViewHolder>
       if (position != null)
         notifyItemChanged(position);
     });
+
+    mViewModel.getCheatDeletedEvent().observe(owner, (position) ->
+    {
+      if (position != null)
+        notifyItemRemoved(position);
+    });
   }
 
   @NonNull

Source/Android/app/src/main/res/layout/fragment_cheat_details.xml

@@ -141,7 +141,18 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         app:barrierDirection="top"
-        app:constraint_referenced_ids="button_edit,button_cancel,button_ok" />
+        app:constraint_referenced_ids="button_delete,button_edit,button_cancel,button_ok" />
+
+    <Button
+        android:id="@+id/button_delete"
+        android:layout_width="0dp"
+        android:layout_height="wrap_content"
+        android:layout_margin="@dimen/spacing_large"
+        android:text="@string/cheats_delete"
+        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintEnd_toStartOf="@id/button_edit"
+        app:layout_constraintTop_toBottomOf="@id/barrier"
+        app:layout_constraintBottom_toBottomOf="parent" />
 
     <Button
         android:id="@+id/button_edit"
@@ -149,7 +160,7 @@
         android:layout_height="wrap_content"
         android:layout_margin="@dimen/spacing_large"
         android:text="@string/cheats_edit"
-        app:layout_constraintStart_toStartOf="parent"
+        app:layout_constraintStart_toEndOf="@id/button_delete"
         app:layout_constraintEnd_toStartOf="@id/button_cancel"
         app:layout_constraintTop_toBottomOf="@id/barrier"
         app:layout_constraintBottom_toBottomOf="parent" />

Source/Android/app/src/main/res/values/strings.xml

@@ -400,6 +400,8 @@
     <string name="cheats_notes">Notes</string>
     <string name="cheats_code">Code</string>
     <string name="cheats_edit">Edit</string>
+    <string name="cheats_delete">Delete</string>
+    <string name="cheats_delete_confirmation">Are you sure you want to delete "%1$s"?</string>
     <string name="cheats_error_no_name">Name can\'t be empty</string>
     <string name="cheats_error_no_code_lines">Code can\'t be empty</string>
     <string name="cheats_error_on_line">Error on line %1$d</string>