Implement default assist app setting

- Add "None" support to AppListPreference
- Add DefaultAssistPreference to manage assist;
- Add AppListPreferenceWithSettings to show a settings icon;
- Implement DefaultAssistPreference based on AppListPreferenceWithSettings;
- Move voice input settings into ManageAssist and implement it
  based on AppListPreferenceWithSettings;

Bug:20210110
Change-Id: If283b8b55a46b428ecfa6e45dc2123292b1d4302

src/com/android/settings/voice/VoiceInputListPreference.java

@@ -0,0 +1,148 @@
+package com.android.settings.voice;
+
+import android.content.ComponentName;
+import android.content.Context;
+import android.provider.Settings;
+import android.util.AttributeSet;
+import android.view.View;
+import android.view.ViewGroup;
+import android.widget.ArrayAdapter;
+import android.widget.ListAdapter;
+
+import com.android.settings.AppListPreferenceWithSettings;
+import com.android.settings.R;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class VoiceInputListPreference extends AppListPreferenceWithSettings {
+
+    private VoiceInputHelper mHelper;
+
+    // The assist component name to restrict available voice inputs.
+    private ComponentName mAssistRestrict;
+
+    private final List<Integer> mAvailableIndexes = new ArrayList<>();
+
+    public VoiceInputListPreference(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        setDialogTitle(R.string.choose_voice_input_title);
+    }
+
+    @Override
+    protected ListAdapter createListAdapter() {
+        return new CustomAdapter(getContext(), getEntries());
+    }
+
+    @Override
+    protected boolean persistString(String value) {
+        for (int i = 0; i < mHelper.mAvailableInteractionInfos.size(); ++i) {
+            VoiceInputHelper.InteractionInfo info = mHelper.mAvailableInteractionInfos.get(i);
+            if (info.key.equals(value)) {
+                Settings.Secure.putString(getContext().getContentResolver(),
+                        Settings.Secure.VOICE_INTERACTION_SERVICE, value);
+                Settings.Secure.putString(getContext().getContentResolver(),
+                        Settings.Secure.VOICE_RECOGNITION_SERVICE,
+                        new ComponentName(info.service.packageName,
+                                info.serviceInfo.getRecognitionService())
+                                .flattenToShortString());
+                setSummary(getEntry());
+                setSettingsComponent(info.settings);
+                return true;
+            }
+        }
+
+        for (int i = 0; i < mHelper.mAvailableRecognizerInfos.size(); ++i) {
+            VoiceInputHelper.RecognizerInfo info = mHelper.mAvailableRecognizerInfos.get(i);
+            if (info.key.equals(value)) {
+                Settings.Secure.putString(getContext().getContentResolver(),
+                        Settings.Secure.VOICE_INTERACTION_SERVICE, "");
+                Settings.Secure.putString(getContext().getContentResolver(),
+                        Settings.Secure.VOICE_RECOGNITION_SERVICE, value);
+                setSummary(getEntry());
+                setSettingsComponent(info.settings);
+               return true;
+            }
+        }
+
+        setSettingsComponent(null);
+        return true;
+    }
+
+    @Override
+    public void setPackageNames(CharSequence[] packageNames, CharSequence defaultPackageName) {
+        // Skip since all entries are created from |mHelper|.
+    }
+
+    public void setAssistRestrict(ComponentName assistRestrict) {
+        mAssistRestrict = assistRestrict;
+    }
+
+    public void refreshVoiceInputs() {
+        mHelper = new VoiceInputHelper(getContext());
+        mHelper.buildUi();
+
+        final String assistKey =
+                mAssistRestrict == null ? "" : mAssistRestrict.flattenToShortString();
+
+        mAvailableIndexes.clear();
+        List<CharSequence> entries = new ArrayList<>();
+        List<CharSequence> values = new ArrayList<>();
+        for (int i = 0; i < mHelper.mAvailableInteractionInfos.size(); ++i) {
+            VoiceInputHelper.InteractionInfo info = mHelper.mAvailableInteractionInfos.get(i);
+            entries.add(info.appLabel);
+            values.add(info.key);
+
+            if (info.key.contentEquals(assistKey)) {
+                mAvailableIndexes.add(i);
+            }
+        }
+
+        final boolean assitIsService = !mAvailableIndexes.isEmpty();
+        final int serviceCount = entries.size();
+
+        for (int i = 0; i < mHelper.mAvailableRecognizerInfos.size(); ++i) {
+            VoiceInputHelper.RecognizerInfo info = mHelper.mAvailableRecognizerInfos.get(i);
+            entries.add(info.label);
+            values.add(info.key);
+            if (!assitIsService) {
+                mAvailableIndexes.add(serviceCount + i);
+            }
+        }
+        setEntries(entries.toArray(new CharSequence[entries.size()]));
+        setEntryValues(values.toArray(new CharSequence[values.size()]));
+
+        if (mHelper.mCurrentVoiceInteraction != null) {
+            setValue(mHelper.mCurrentVoiceInteraction.flattenToShortString());
+        } else if (mHelper.mCurrentRecognizer != null) {
+            setValue(mHelper.mCurrentRecognizer.flattenToShortString());
+        } else {
+            setValue(null);
+        }
+    }
+
+    private class CustomAdapter extends ArrayAdapter<CharSequence> {
+
+        public CustomAdapter(Context context, CharSequence[] objects) {
+            super(context, com.android.internal.R.layout.select_dialog_singlechoice_material,
+                    android.R.id.text1, objects);
+        }
+
+        @Override
+        public boolean areAllItemsEnabled() {
+            return false;
+        }
+
+        @Override
+        public boolean isEnabled(int position) {
+            return mAvailableIndexes.contains(position);
+        }
+
+        @Override
+        public View getView(int position, View convertView, ViewGroup parent) {
+            View view = super.getView(position, convertView, parent);
+            view.setEnabled(isEnabled(position));
+            return view;
+        }
+    }
+}