Remove battery symbol(icon) in QuickSettings

Android: 4.4.2

在status bar上(右上角時間那個)，由上往下滑，會出現下拉選單，上面有BRIGHTNESS，SETTINGS, WIFI, BLUETOOTH等符號，在android裡，這個選單叫Quick Setting

frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/phone/QuickSettings.java

// Battery
        final QuickSettingsTileView batteryTile = (QuickSettingsTileView)
                inflater.inflate(R.layout.quick_settings_tile, parent, false);
        batteryTile.setContent(R.layout.quick_settings_tile_battery, inflater);
        batteryTile.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startSettingsActivity(Intent.ACTION_POWER_USAGE_SUMMARY);
            }
        });
        mModel.addBatteryTile(batteryTile, new QuickSettingsModel.RefreshCallback() {
            @Override
            public void refreshView(QuickSettingsTileView unused, State state) {
                QuickSettingsModel.BatteryState batteryState =
                        (QuickSettingsModel.BatteryState) state;
                String t;
                if (batteryState.batteryLevel == 100) {
                    t = mContext.getString(R.string.quick_settings_battery_charged_label);
                } else {
                    t = batteryState.pluggedIn
                        ? mContext.getString(R.string.quick_settings_battery_charging_label,
                                batteryState.batteryLevel)
                        : mContext.getString(R.string.status_bar_settings_battery_meter_format,
                                batteryState.batteryLevel);
                }
                ((TextView)batteryTile.findViewById(R.id.text)).setText(t);
                batteryTile.setContentDescription(
                        mContext.getString(R.string.accessibility_quick_settings_battery, t));
            }
        });
        parent.addView(batteryTile);

這裡最後一行很明顯，把它marked掉就能把battery的symbol給拿掉