Implement a bluetooth picker dialog for Android

chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java

Index: chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java b/chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java
index 6c92d6240828507a80d4aea4012f7601389e50fa..ea2027d75611f1199636ac69ec7491d5965c3ba2 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/ItemChooserDialog.java
@@ -6,6 +6,7 @@ package org.chromium.chrome.browser;
 
 import android.app.Dialog;
 import android.content.Context;
+import android.content.DialogInterface;
 import android.graphics.Color;
 import android.graphics.drawable.ColorDrawable;
 import android.text.SpannableString;
@@ -30,7 +31,9 @@ import org.chromium.chrome.R;
 import org.chromium.ui.base.DeviceFormFactor;
 import org.chromium.ui.widget.TextViewWithClickableSpans;
 
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
 /**
  * A general-purpose dialog for presenting a list of things to pick from.
@@ -75,20 +78,36 @@ public class ItemChooserDialog {
         public final SpannableString mNoneFound;
         // A status message to show above the button row.
         public final SpannableString mStatus;
+        // An error state.
+        public final SpannableString mErrorMessage;
+        // A status message to go with the error state.
+        public final SpannableString mErrorStatus;
         // The label for the positive button (e.g. Select/Pair).
         public final String mPositiveButton;
 
         public ItemChooserLabels(SpannableString title, String searching, SpannableString noneFound,
-                SpannableString status, String positiveButton) {
+                SpannableString status, SpannableString errorMessage, SpannableString errorStatus,
+                String positiveButton) {
             mTitle = title;
             mSearching = searching;
             mNoneFound = noneFound;
             mStatus = status;
+            mErrorMessage = errorMessage;
+            mErrorStatus = errorStatus;
             mPositiveButton = positiveButton;
         }
     }
 
     /**
+     * The various states the dialog can represent.
+     */
+    private enum State {
+        STARTING,
+        PROGRESS_UPDATE_AVAILABLE,
+        SHOWING_ERROR,
+    }
+
+    /**
      * An adapter for keeping track of which items to show in the dialog.
      */
     private class ItemAdapter extends ArrayAdapter<ItemChooserRow>
@@ -105,6 +124,9 @@ public class ItemChooserDialog {
         // or -1 (INVALID_POSITION) if nothing is selected.
         private int mSelectedItem = ListView.INVALID_POSITION;
 
+        // A set of keys that are marked as disabled in the dialog.
+        private Set<String> mDisabledEntries = new HashSet<String>();
+
         public ItemAdapter(Context context, int resource) {
             super(context, resource);
 
@@ -133,6 +155,26 @@ public class ItemChooserDialog {
             return row.mKey;
         }
 
+        /**
+         * Sets whether the itam is enabled. Disabled items are grayed out.
+         * @param id The id of the item to affect.
+         * @param enabled Whether the item should be enabled or not.
+         */
+        public void setEnabled(String id, boolean enabled) {
+            if (enabled) {
+                mDisabledEntries.remove(id);
+            } else {
+                mDisabledEntries.add(id);
+            }
+            notifyDataSetChanged();
+        }
+
+        @Override
+        public boolean isEnabled(int position) {
+            ItemChooserRow item = getItem(position);
+            return !mDisabledEntries.contains(item.mKey);
+        }
+
         @Override
         public int getViewTypeCount() {
             return 1;
@@ -159,7 +201,12 @@ public class ItemChooserDialog {
                 view.setTextColor(Color.WHITE);
             } else {
                 view.setBackground(null);
-                view.setTextColor(mDefaultTextColor);
+                if (!isEnabled(position)) {
+                    view.setTextColor(getContext().getResources().getColor(
+                            R.color.primary_text_disabled_material_light));
+                } else {
+                    view.setTextColor(mDefaultTextColor);
+                }
             }
 
             ItemChooserRow item = getItem(position);
@@ -185,7 +232,7 @@ public class ItemChooserDialog {
 
     // Individual UI elements.
     private TextViewWithClickableSpans mTitle;
-    private TextViewWithClickableSpans mNotFoundMessage;
+    private TextViewWithClickableSpans mEmptyMessage;
     private ProgressBar mProgressBar;
     private ListView mListView;
     private TextView mStatus;
@@ -225,17 +272,13 @@ public class ItemChooserDialog {
         mStatus = (TextView) dialogContainer.findViewById(R.id.status);
         mTitle = (TextViewWithClickableSpans) dialogContainer.findViewById(
                 R.id.dialog_title);
-        mNotFoundMessage =
-                (TextViewWithClickableSpans) dialogContainer.findViewById(
-                        R.id.not_found_message);
+        mEmptyMessage =
+                (TextViewWithClickableSpans) dialogContainer.findViewById(R.id.not_found_message);
 
         mTitle.setText(labels.mTitle);
         mTitle.setMovementMethod(LinkMovementMethod.getInstance());
 
-        mNotFoundMessage.setText(labels.mNoneFound);
-        mNotFoundMessage.setMovementMethod(LinkMovementMethod.getInstance());
-
-        mStatus.setText(labels.mSearching);
+        mEmptyMessage.setMovementMethod(LinkMovementMethod.getInstance());
         mStatus.setMovementMethod(LinkMovementMethod.getInstance());
 
         mConfirmButton = (Button) dialogContainer.findViewById(R.id.positive);
@@ -252,10 +295,10 @@ public class ItemChooserDialog {
 
         mItemAdapter = new ItemAdapter(mContext, R.layout.item_chooser_dialog_row);
         mListView.setAdapter(mItemAdapter);
-        mListView.setEmptyView(mNotFoundMessage);
-        mNotFoundMessage.setVisibility(View.GONE);
+        mListView.setEmptyView(mEmptyMessage);
         mListView.setOnItemClickListener(mItemAdapter);
         mListView.setDivider(null);
+        setState(State.STARTING);
 
         // The list is the main element in the dialog and it should grow and
         // shrink according to the size of the screen available (clamped to a
@@ -282,6 +325,12 @@ public class ItemChooserDialog {
         mDialog.addContentView(view,
                 new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,
                                               LinearLayout.LayoutParams.MATCH_PARENT));
+        mDialog.setOnDismissListener(new DialogInterface.OnDismissListener() {
+            @Override
+            public void onDismiss(DialogInterface dialog) {
+                mItemSelectedCallback.onItemSelected("");

[newt (away), 2015/09/02 17:48:42]

Seems like you'll end up calling onItemSelected() twice if the user clicks the
confirm button: once with the selected item's key and once with the empty
string. Is that what you want?

[Finnur, 2015/09/03 11:51:45]

Both handlers do, indeed, fire, but the second message never reaches the native
level. However, it isn't necessary to keep the onDismiss handler once the
onClick handler (for the commit button fires), so I now null it there just to
make sure.

+            }
+        });
 
         Window window = mDialog.getWindow();
         if (!DeviceFormFactor.isTablet(mContext)) {
@@ -296,6 +345,10 @@ public class ItemChooserDialog {
         mDialog.show();
     }
 
+    public void dismiss() {
+        mDialog.dismiss();
+    }
+
     /**
      * Add items to show in the dialog.
      *
@@ -306,17 +359,20 @@ public class ItemChooserDialog {
      */
     public void showList(List<ItemChooserRow> list) {
         mProgressBar.setVisibility(View.GONE);
-        mStatus.setText(mLabels.mStatus);
-
-        if (list.isEmpty()) {
-            boolean showEmptyMessage = mItemAdapter.isEmpty();
-            mNotFoundMessage.setVisibility(
-                    showEmptyMessage ? View.VISIBLE : View.GONE);
-            mListView.setVisibility(showEmptyMessage ? View.GONE : View.VISIBLE);
-        } else {
-            mListView.setVisibility(View.VISIBLE);
+
+        if (!list.isEmpty()) {
             mItemAdapter.addAll(list);
         }
+        setState(State.PROGRESS_UPDATE_AVAILABLE);
+    }
+
+    /**
+     * Sets whether the item is enabled.
+     * @param id The id of the item to affect.
+     * @param enabled Whether the item should be enabled or not.
+     */
+    public void setEnabled(String id, boolean enabled) {
+        mItemAdapter.setEnabled(id, enabled);
     }
 
     /**
@@ -324,5 +380,37 @@ public class ItemChooserDialog {
      */
     public void clear() {
         mItemAdapter.clear();
+        setState(State.STARTING);
+    }
+
+    /**
+     * Set the error state for the dialog.
+     */
+    public void setErrorState() {
+        setState(State.SHOWING_ERROR);
+    }
+
+    private void setState(State state) {
+        switch (state) {
+            case STARTING:
+                mStatus.setText(mLabels.mSearching);
+                mListView.setVisibility(View.GONE);
+                mProgressBar.setVisibility(View.VISIBLE);
+                break;
+            case SHOWING_ERROR:
+                mProgressBar.setVisibility(View.GONE);
+                mEmptyMessage.setText(mLabels.mErrorMessage);
+                mStatus.setText(mLabels.mErrorStatus);
+                break;
+            case PROGRESS_UPDATE_AVAILABLE:
+                mStatus.setText(mLabels.mStatus);
+                mProgressBar.setVisibility(View.GONE);
+                mListView.setVisibility(View.VISIBLE);
+
+                boolean showEmptyMessage = mItemAdapter.isEmpty();
+                mEmptyMessage.setText(mLabels.mNoneFound);
+                mEmptyMessage.setVisibility(showEmptyMessage ? View.VISIBLE : View.GONE);
+                break;
+        }
     }
 }