Android源碼開發筆記 軟鍵盤與內置物理鍵盤共存以及外接藍牙鍵盤不共存邏輯
需求1： android設備自帶九鍵的小鍵盤，此時小鍵盤被識別為HW Keyboard，默認與軟鍵盤不能共存，需要使軟鍵盤與物理鍵盤共存。
實現：
在網上找的別人總結的Android5.1的解決方法，需要解決的codebase為Android6.0，都可以用。
方法一：（此方法在Android8.0 codebase已不可用） frameworks/base/services/core/java/com/android/server/wm/WindowManagerService.java中，如果把updateShowImeWithHardKeyboard()方法中的showImeWithHardKeyboard變量直接置為true，則可以實現軟鍵盤與物理鍵盤的同時使用。（原本為讀取Setting數據庫字段來判斷，所以也可以直接修改Setting字段來實現）
public void updateShowImeWithHardKeyboard() { synchronized (mWindowMap) { final boolean showImeWithHardKeyboard = Settings.Secure.getIntForUser( mContext.getContentResolver(), Settings.Secure.SHOW_IME_WITH_HARD_KEYBOARD, 0, mCurrentUserId)== 1;if (mShowImeWithHardKeyboard != showImeWithHardKeyboard) { mShowImeWithHardKeyboard = showImeWithHardKeyboard; mH.sendEmptyMessage(H.SEND_NEW_CONFIGURATION); } } }
方法二：frameworks/base/core/java/android/inputmethodservice/InputMethodService.java，修改onEvaluateInputViewShown()方法直接返回true
public boolean onEvaluateInputViewShown() { Configuration config = getResources().getConfiguration(); //return config.keyboard == Configuration.KEYBOARD_NOKEYS // || config.hardKeyboardHidden == Configuration.HARDKEYBOARDHIDDEN_YES; return true; }
方法三：在外部需要修改的合適位置，直接將Setting字段修改掉，隨時可以改回來，一勞永逸。
Settings.Secure.putInt(mContext.getContentResolver(), Settings.Secure.SHOW_IME_WITH_HARD_KEYBOARD, 1);// 1: Disabled,0: Enabled
需求2：軟鍵盤與內置物理鍵盤共存基礎上，再外接藍牙鍵盤。此時外接藍牙鍵盤與軟鍵盤不可共存。
分析：此時外接鍵盤也被視為物理鍵盤，按照上面需求1的方法修改後，使藍牙鍵盤與軟鍵盤是共存的，所以不符合需求。需要找到藍牙鍵盤連接上的位置，來把前面需求1改的地方取消掉。
即：未連接藍牙鍵盤時，將Setting字段改為共存模式，使軟鍵盤與內置物理鍵盤共存；連接藍牙鍵盤後，將Setting字段改為不共存模式，使軟鍵盤與藍牙鍵盤不共存（此時藍牙鍵盤與內置物理鍵盤是共存的）。
實現：本需求的難點為找到恰當的位置來修改Setting字段，此恰當位置為：藍牙鍵盤連接成功或斷開，以及藍牙關閉。
實現分析流程：
1. 通過Settings中Bluetooth Settings部分可以看到，連接藍牙鍵盤時，藍牙設備的類型已經可以通過圖標區分出來。這樣就不用懷疑是否能夠區分藍牙鍵盤和其他藍牙設備了。
在packages/apps/Settings/src/com/android/settings/bluetooth/BluetoothDevicePreference.java中根據icon可以看到，不同種類的BT device已經可以區分了。
private int getBtClassDrawable() { BluetoothClass btClass = mCachedDevice.getBtClass(); if (btClass != null) { switch (btClass.getMajorDeviceClass()) { case BluetoothClass.Device.Major.COMPUTER: return R.drawable.ic_bt_laptop; case BluetoothClass.Device.Major.PHONE: return R.drawable.ic_bt_cellphone; case BluetoothClass.Device.Major.PERIPHERAL: return HidProfile.getHidClassDrawable(btClass); case BluetoothClass.Device.Major.IMAGING: return R.drawable.ic_bt_imaging; default: // unrecognized device class; continue } } else { Log.w(TAG, "mBtClass is null"); } ...
需要的藍牙鍵盤在 HidProfile.getHidClassDrawable(btClass)獲得。
frameworks/base/packages/SettingsLib/src/com/android/settingslib/bluetooth/HidProfile.java
public static int getHidClassDrawable(BluetoothClass btClass) { switch (btClass.getDeviceClass()) { case BluetoothClass.Device.PERIPHERAL_KEYBOARD: case BluetoothClass.Device.PERIPHERAL_KEYBOARD_POINTING: return R.drawable.ic_lockscreen_ime; case BluetoothClass.Device.PERIPHERAL_POINTING: return R.drawable.ic_bt_pointing_hid; default: return R.drawable.ic_bt_misc_hid; } }
2. 通過抓系統藍牙profile log來確認斷開連接藍牙鍵盤時，會在framework裏面的Bluetooth的哪邊被trigger到。
adb logcat |grep Profile
在連接/斷開藍牙鍵盤時，可以抓到下面的log：
kunkka@kunkka-Lenovo:~$ adb logcat |grep Profile 12-22 03:55:00.524 1257 1257 I SystemServer: SamplingProfiler Service 12-22 04:29:41.923 3916 4051 D CachedBluetoothDevice: onProfileStateChanged: profile HID newProfileState 0 12-22 06:25:59.666 7284 7284 D CachedBluetoothDevice: onProfileStateChanged: profile HID newProfileState 2 12-22 06:25:59.668 3916 4051 D CachedBluetoothDevice: onProfileStateChanged: profile HID newProfileState 2 12-22 06:26:33.245 7284 7284 D CachedBluetoothDevice: onProfileStateChanged: profile HID newProfileState 0 12-22 06:26:33.245 3916 4051 D CachedBluetoothDevice: onProfileStateChanged: profile HID newProfileState 0 12-22 06:26:45.586 7284 7284 D CachedBluetoothDevice: onProfileStateChanged: profile HID newProfileState 2 12-22 06:26:45.587 3916 4051 D CachedBluetoothDevice: onProfileStateChanged: profile HID newProfileState 2 ...
可以定位到frameworks/base/packages/SettingsLib/src/com/android/settingslib/bluetooth/CachedBluetoothDevice.java
在onProfileStateChanged方法中可以看到，藍牙連接和斷開時都可以走到！而且去獲得藍牙設備類型的context也都有！這樣問題解決一大半！
在onProfileStateChanged方法中添加藍牙連接和斷開時的設備類型判斷：
if(mBtClass.getMajorDeviceClass() == BluetoothClass.Device.Major.PERIPHERAL && (mBtClass.getDeviceClass() == BluetoothClass.Device.PERIPHERAL_KEYBOARD || mBtClass.getDeviceClass() == BluetoothClass.Device.PERIPHERAL_KEYBOARD_POINTING)) { Log.i("Kunkka0", "getMajorDeviceClass = Peripheral & getDeviceClass = KeyBoard"); if(newProfileState == 0) {// Disconnected Log.i("Kunkka0","SET SHOW_IME_WITH_HARD_KEYBOARD TO 1"); Settings.Secure.putInt(mContext.getContentResolver(), Settings.Secure.SHOW_IME_WITH_HARD_KEYBOARD, 1); }else { Log.i("Kunkka0","SET SHOW_IME_WITH_HARD_KEYBOARD TO 0"); Settings.Secure.putInt(mContext.getContentResolver(), Settings.Secure.SHOW_IME_WITH_HARD_KEYBOARD, 0); } }else { Log.i("Kunkka0","getMajorDeviceClass() = "+mBtClass.getMajorDeviceClass()+", getDeviceClass = "+mBtClass.getDeviceClass()); Log.i("Kunkka0","PERIPHERAL = 1280, PERIPHERAL_KEYBOARD = 1344, PERIPHERAL_KEYBOARD_POINTING = 1472"); }
加完編譯出image來測試，功能實現！
但是，在關閉藍牙時，藍牙鍵盤就不能用了，但是此處不能收到狀態變化！此時，關閉藍牙，軟鍵盤和藍牙鍵盤都不能用了！
3. 為了解決關閉藍牙時的問題，再去搜索藍牙開關狀態變化的事件：
在frameworks/base/packages/SettingsLib/src/com/android/settingslib/bluetooth/BluetoothCallback.java中可以看到有：
void onBluetoothStateChanged(int bluetoothState); void onScanningStateChanged(boolean started); void onDeviceAdded(CachedBluetoothDevice cachedDevice); void onDeviceDeleted(CachedBluetoothDevice cachedDevice); void onDeviceBondStateChanged(CachedBluetoothDevice cachedDevice, int bondState); void onConnectionStateChanged(CachedBluetoothDevice cachedDevice, int state);
查看所有重載此事件的class，Open implementation-可以看到：
下面幾個都是Settings中的，但我們的需求不止在Settings中，所以看上面KeyboardUI和systemui下面的statusbar。
StatusBar下面的BluetoothControllerImpl比較符合。
打開frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/policy/BluetoothControllerImpl.java
除了onBluetoothStateChanged外還有個updateConnected()方法，居然也可以偵測藍牙設備連接狀態！
所以我們只需要在onBluetoothStateChanged()和updateConnected()中都加入事件偵測來修改Settings字段就可以了！
4. 最終解決辦法：
a. 在onBluetoothStateChanged()中，當藍牙關閉時，使鍵盤共存，保證軟鍵盤和內置物理鍵盤的共存。
@Override public void onBluetoothStateChanged(int bluetoothState) { mEnabled = bluetoothState == BluetoothAdapter.STATE_ON; if(!mEnabled) { Log.i("Kunkka0","onBluetoothStateChanged: SET SHOW_IME_WITH_HARD_KEYBOARD TO 1"); Settings.Secure.putInt(mContext.getContentResolver(), Settings.Secure.SHOW_IME_WITH_HARD_KEYBOARD, 1); } mHandler.sendEmptyMessage(H.MSG_STATE_CHANGED); }
b. 在updateConnected()中，當藍牙鍵盤連接時，使軟硬鍵盤不共存，藍牙鍵盤斷開時，使軟硬件盤共存。
private void updateConnected() { ... for (CachedBluetoothDevice device : getDevices()) { if (device.isConnected()) { mLastDevice = device; } if(device.getBtClass().getMajorDeviceClass() == BluetoothClass.Device.Major.PERIPHERAL && (device.getBtClass().getDeviceClass() == BluetoothClass.Device.PERIPHERAL_KEYBOARD || device.getBtClass().getDeviceClass() == BluetoothClass.Device.PERIPHERAL_KEYBOARD_POINTING)) { Log.i("Kunkka0", "getMajorDeviceClass = Peripheral & getDeviceClass = KeyBoard"); if(!device.isConnected()) {// Disconnected Log.i("Kunkka0","SET SHOW_IME_WITH_HARD_KEYBOARD TO 1"); Settings.Secure.putInt(mContext.getContentResolver(), Settings.Secure.SHOW_IME_WITH_HARD_KEYBOARD, 1); }else { Log.i("Kunkka0","SET SHOW_IME_WITH_HARD_KEYBOARD TO 0"); Settings.Secure.putInt(mContext.getContentResolver(), Settings.Secure.SHOW_IME_WITH_HARD_KEYBOARD, 0); } }else { Log.i("Kunkka0","getMajorDeviceClass() = "+device.getBtClass().getMajorDeviceClass()+", getDeviceClass = "+device.getBtClass().getDeviceClass()); Log.i("Kunkka0","PERIPHERAL = 1280, PERIPHERAL_KEYBOARD = 1344, PERIPHERAL_KEYBOARD_POINTING = 1472"); } } ... }
測試，驗證通過！
Android源碼開發筆記 軟鍵盤與內置物理鍵盤共存以及外接藍牙鍵盤不共存邏輯