NFC: async enabling/disabling, ala Bluewooth & Wifi. (d36d650a) · Commits · e / os / android_packages_apps_Settings

res/values/strings.xml

+1 −0

Original line number	Diff line number	Diff line
		@@ -784,6 +784,7 @@
		<string name="nfc_quick_toggle_title">NFC</string>
		<!-- Used in the 1st-level settings screen as the turn-on summary -->
		<string name="nfc_quick_toggle_summary">Use Near Field Communication to read and exchange tags</string>
		<string name="nfc_toggle_error" msgid="8998642457947607263">An error occurred.</string>

		<!-- Wi-Fi Settings --> <skip />
		<!-- Used in the 1st-level settings screen to turn on Wi-Fi -->

src/com/android/settings/nfc/NfcEnabler.java

+61 −25

Original line number	Diff line number	Diff line
		@@ -17,10 +17,15 @@
		package com.android.settings.nfc;

		import com.android.settings.R;

		import android.content.BroadcastReceiver;
		import android.content.Context;
		import android.content.Intent;
		import android.content.IntentFilter;
		import android.nfc.NfcAdapter;
		import android.preference.Preference;
		import android.os.Handler;
		import android.preference.CheckBoxPreference;
		import android.preference.Preference;
		import android.provider.Settings;
		import android.util.Log;

		@@ -35,6 +40,20 @@ public class NfcEnabler implements Preference.OnPreferenceChangeListener {
		private final Context mContext;
		private final CheckBoxPreference mCheckbox;
		private final NfcAdapter mNfcAdapter;
		private final IntentFilter mIntentFilter;
		private final Handler mHandler = new Handler();

		private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
		@Override
		public void onReceive(Context context, Intent intent) {
		String action = intent.getAction();
		if (NfcAdapter.ACTION_ADAPTER_STATE_CHANGE.equals(action)) {
		handleNfcStateChanged(intent.getBooleanExtra(
		NfcAdapter.EXTRA_NEW_BOOLEAN_STATE,
		false));
		}
		}
		};

		private boolean mNfcState;

		@@ -47,49 +66,66 @@ public class NfcEnabler implements Preference.OnPreferenceChangeListener {
		// NFC is not supported
		mCheckbox.setEnabled(false);
		}

		mIntentFilter = new IntentFilter(NfcAdapter.ACTION_ADAPTER_STATE_CHANGE);

		}

		public void resume() {
		if (mNfcAdapter == null) {
		return;
		}
		mContext.registerReceiver(mReceiver, mIntentFilter);
		mCheckbox.setOnPreferenceChangeListener(this);
		mNfcState = Settings.System.getInt(mContext.getContentResolver(),
		Settings.System.NFC_ON, 0) != 0;
		updateUi();
		mCheckbox.setChecked(mNfcState);
		}

		public void pause() {
		if (mNfcAdapter == null) {
		return;
		}
		mContext.unregisterReceiver(mReceiver);
		mCheckbox.setOnPreferenceChangeListener(null);
		}

		public boolean onPreferenceChange(Preference preference, Object value) {
		// Turn on/off Nfc
		mNfcState = (Boolean) value;
		setEnabled();
		// Turn NFC on/off

		return false;
		}
		final boolean desiredState = (Boolean) value;
		mCheckbox.setEnabled(false);

		private void setEnabled() {
		if (mNfcState) {
		if (!mNfcAdapter.enableTagDiscovery()) {
		Log.w(TAG, "NFC enabling failed");
		mNfcState = false;
		// Start async update of the NFC adapter state, as the API is
		// unfortunately blocking...
		new Thread("toggleNFC") {
		public void run() {
		Log.d(TAG, "Setting NFC enabled state to: " + desiredState);
		boolean success = false;
		if (desiredState) {
		success = mNfcAdapter.enableTagDiscovery();
		} else {
		success = mNfcAdapter.disableTagDiscovery();
		}
		if (success) {
		Log.d(TAG, "Successfully changed NFC enabled state to " + desiredState);
		// UI will be updated by BroadcastReceiver, above.
		} else {
		if (!mNfcAdapter.disableTagDiscovery()) {
		Log.w(TAG, "NFC disabling failed");
		mNfcState = true;
		Log.w(TAG, "Error setting NFC enabled state to " + desiredState);
		mHandler.post(new Runnable() {
		public void run() {
		mCheckbox.setEnabled(true);
		mCheckbox.setSummary(R.string.nfc_toggle_error);
		}
		});
		}
		}
		updateUi();
		}.start();
		return false;
		}

		private void updateUi() {
		mCheckbox.setChecked(mNfcState);
		private void handleNfcStateChanged(boolean newState) {
		mCheckbox.setChecked(newState);
		mCheckbox.setEnabled(true);
		}
		}