auto import from //depot/cupcake/@135843

src/com/android/settings/bluetooth/BluetoothEnabler.java

@@ -0,0 +1,149 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings.bluetooth;
+
+import com.android.settings.R;
+import com.android.settings.bluetooth.LocalBluetoothManager.ExtendedBluetoothState;
+
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.preference.Preference;
+import android.preference.CheckBoxPreference;
+import android.text.TextUtils;
+import android.util.Config;
+
+/**
+ * BluetoothEnabler is a helper to manage the Bluetooth on/off checkbox
+ * preference. It is turns on/off Bluetooth and ensures the summary of the
+ * preference reflects the current state.
+ */
+public class BluetoothEnabler implements Preference.OnPreferenceChangeListener {
+    
+    private static final boolean LOCAL_LOGD = Config.LOGD || false;
+    private static final String TAG = "BluetoothEnabler";
+    
+    private final Context mContext; 
+    private final CheckBoxPreference mCheckBoxPreference;
+    private final CharSequence mOriginalSummary;
+    
+    private final LocalBluetoothManager mLocalManager;
+
+    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
+        @Override
+        public void onReceive(Context context, Intent intent) {
+            handleStateChanged(mLocalManager.getBluetoothState());
+        }
+    };
+
+    public BluetoothEnabler(Context context, CheckBoxPreference checkBoxPreference) {
+        mContext = context;
+        mCheckBoxPreference = checkBoxPreference;
+        
+        mOriginalSummary = checkBoxPreference.getSummary();
+        checkBoxPreference.setPersistent(false);
+        
+        mLocalManager = LocalBluetoothManager.getInstance(context);
+        if (mLocalManager == null) {
+            // Bluetooth not supported
+            checkBoxPreference.setEnabled(false);
+        }
+    }
+
+    public void resume() {
+        if (mLocalManager == null) {
+            return;
+        }
+        
+        ExtendedBluetoothState state = mLocalManager.getBluetoothState();
+        // This is the widget enabled state, not the preference toggled state
+        mCheckBoxPreference.setEnabled(state == ExtendedBluetoothState.ENABLED ||
+                state == ExtendedBluetoothState.DISABLED);
+        // BT state is not a sticky broadcast, so set it manually
+        handleStateChanged(state);
+        
+        mContext.registerReceiver(mReceiver, 
+                new IntentFilter(LocalBluetoothManager.EXTENDED_BLUETOOTH_STATE_CHANGED_ACTION));
+        mCheckBoxPreference.setOnPreferenceChangeListener(this);
+    }
+    
+    public void pause() {
+        if (mLocalManager == null) {
+            return;
+        }
+        
+        mContext.unregisterReceiver(mReceiver);
+        mCheckBoxPreference.setOnPreferenceChangeListener(null);
+    }
+    
+    public boolean onPreferenceChange(Preference preference, Object value) {
+        // Turn on/off BT
+        setEnabled((Boolean) value);
+        
+        // Don't update UI to opposite state until we're sure
+        return false;
+    }
+    
+    private void setEnabled(final boolean enable) {
+        // Disable preference
+        mCheckBoxPreference.setEnabled(false);
+        
+        mLocalManager.setBluetoothEnabled(enable);
+    }
+    
+    private void handleStateChanged(ExtendedBluetoothState state) {
+
+        if (state == ExtendedBluetoothState.DISABLED || state == ExtendedBluetoothState.ENABLED) {
+            mCheckBoxPreference.setChecked(state == ExtendedBluetoothState.ENABLED);
+            mCheckBoxPreference
+                    .setSummary(state == ExtendedBluetoothState.DISABLED ? mOriginalSummary : null);
+            
+            mCheckBoxPreference.setEnabled(isEnabledByDependency());
+            
+        } else if (state == ExtendedBluetoothState.ENABLING ||
+                state == ExtendedBluetoothState.DISABLING) {
+            mCheckBoxPreference.setSummary(state == ExtendedBluetoothState.ENABLING
+                    ? R.string.wifi_starting
+                    : R.string.wifi_stopping);
+            
+        } else if (state == ExtendedBluetoothState.UNKNOWN) {
+            mCheckBoxPreference.setChecked(false);
+            mCheckBoxPreference.setSummary(R.string.wifi_error);
+            mCheckBoxPreference.setEnabled(true);
+        }
+    }
+
+    private boolean isEnabledByDependency() {
+        Preference dep = getDependencyPreference();
+        if (dep == null) {
+            return true;
+        }
+        
+        return !dep.shouldDisableDependents();
+    }
+    
+    private Preference getDependencyPreference() {
+        String depKey = mCheckBoxPreference.getDependency();
+        if (TextUtils.isEmpty(depKey)) {
+            return null;
+        }
+        
+        return mCheckBoxPreference.getPreferenceManager().findPreference(depKey);
+    }
+    
+}