向android 的状态栏中加入快捷按钮（home，back，menu等等）的方法（续）

上一篇文章中谈到的加入快捷按钮的方法，实际上还是太过麻烦。那篇博客是在我刚接触android源代码没几天时，参考网上的介绍方法，自己看了下源代码尝试着写了一个。 不过那个方法，是我直接用贴图的方法实现了按钮特效，这实在是太浪费了，最近一直仍有朋友问我那篇文章中的问题，我想还是重写一下，用一个更简单点的方法，直接使用android的ImageButton控件，通过其OnTouchListener方法操作即可，Button的高亮与否完全由系统处理，这样也不会出现button高亮不消失的bug。以下方法在android 2.1 上编译调试通过

1。 准备资源，修改XML文件

和上篇文章一样，准备几张图，这里我们准备添加home back和menu图标，就需要准备6张图，三张普通状态，三张按下的高亮状态图标：

stat_home.png

stat_home_pressed.png

stat_back.png

stat_back_pressed.png

stat_menu.png

stat_menu_pressed.png

同时，在 Frameworks/base/core/res/res/drawable下创建三个imageButton的xml文件：

xml_stat_home.xml

<?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:state_focused="true" android:state_pressed="false" android:drawable="@drawable/stat_home" /> <item android:state_focused="true" android:state_pressed="true" android:drawable="@drawable/stat_home_pressed" /> <item android:state_focused="false" android:state_pressed="true" android:drawable="@drawable/stat_home_pressed" /> <item android:drawable="@drawable/stat_home" /> </selector>

xml_stat_back.xml

<?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:state_focused="true" android:state_pressed="false" android:drawable="@drawable/stat_back" /> <item android:state_focused="true" android:state_pressed="true" android:drawable="@drawable/stat_back_pressed" /> <item android:state_focused="false" android:state_pressed="true" android:drawable="@drawable/stat_back_pressed" /> <item android:drawable="@drawable/stat_back" /> </selector>
xml_stat_menu.xml

<?xml version="1.0" encoding="utf-8"?> <selector xmlns:android="http://schemas.android.com/apk/res/android"> <item android:state_focused="true" android:state_pressed="false" android:drawable="@drawable/stat_menu" /> <item android:state_focused="true" android:state_pressed="true" android:drawable="@drawable/stat_menu_pressed" /> <item android:state_focused="false" android:state_pressed="true" android:drawable="@drawable/stat_menu_pressed" /> <item android:drawable="@drawable/stat_menu" /> </selector>

修改status_bar.xml，如下：

<?xml version="1.0" encoding="utf-8"?> <!-- /* apps/common/assets/default/default/skins/StatusBar.xml ** ** Copyright 2006, 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. */ --> <!-- android:background="@drawable/status_bar_closed_default_background" --> <com.android.server.status.StatusBarView xmlns:android="http://schemas.android.com/apk/res/android" android:background="@drawable/statusbar_background" android:orientation="vertical" android:focusable="true" android:descendantFocusability="afterDescendants" > <LinearLayout android:id="@+id/icons" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="horizontal"> <ImageButton android:id="@+id/go_home" android:layout_width="36px" android:layout_height="36px" android:layout_marginRight="15px" android:layout_marginLeft="10px" android:layout_marginTop="5px" android:clickable="true" android:background="@drawable/xml_stat_home" /> <com.android.server.status.IconMerger android:id="@+id/notificationIcons" android:layout_width="0dip" android:layout_weight="1" android:layout_height="fill_parent" android:layout_alignParentLeft="true" android:paddingLeft="6dip" android:gravity="center_vertical" android:orientation="horizontal"/> <LinearLayout android:id="@+id/statusIcons" android:layout_width="wrap_content" android:layout_height="fill_parent" android:layout_alignParentRight="true" android:paddingRight="6dip" android:gravity="center_vertical" android:orientation="horizontal"/> <ImageButton android:id="@+id/pop_menu" android:layout_width="36px" android:layout_height="36px" android:layout_marginRight="15px" android:layout_marginLeft="10px" android:layout_marginTop="5px" android:clickable="true" android:background="@drawable/xml_stat_menu" /> <ImageButton android:id="@+id/go_back" android:layout_width="36px" android:layout_height="36px" android:layout_marginRight="15px" android:layout_marginLeft="10px" android:layout_marginTop="5px" android:clickable="true" android:background="@drawable/xml_stat_back" /> </LinearLayout> <LinearLayout android:id="@+id/ticker" android:layout_width="fill_parent" android:layout_height="fill_parent" android:paddingLeft="6dip" android:animationCache="false" android:orientation="horizontal" > <ImageSwitcher android:id="@+id/tickerIcon" android:layout_width="wrap_content" android:layout_height="fill_parent" android:layout_marginRight="8dip" > <com.android.server.status.AnimatedImageView android:layout_width="36dip" android:layout_height="36dip" /> <com.android.server.status.AnimatedImageView android:layout_width="36dip" android:layout_height="36dip" /> </ImageSwitcher> <com.android.server.status.TickerView android:id="@+id/tickerText" android:layout_width="0dip" android:layout_weight="1" android:layout_height="wrap_content" android:paddingTop="2dip" android:paddingRight="10dip"> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:singleLine="true" android:textColor="#ff000000" /> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:singleLine="true" android:textColor="#ff000000" /> </com.android.server.status.TickerView> </LinearLayout> <com.android.server.status.DateView android:id="@+id/date" android:layout_width="wrap_content" android:layout_height="fill_parent" android:singleLine="true" android:textSize="20sp" android:textStyle="bold" android:gravity="center_vertical|left" android:paddingLeft="6px" android:paddingRight="6px" android:textColor="?android:attr/textColorPrimaryInverse" android:background="@drawable/statusbar_background" /> </com.android.server.status.StatusBarView>

如上篇，修改statusbar的高度，编译一下，即可看到效果。

2。 添加按钮的动作效果

在statusBarView.java中，活的button的handler

类中新增加三个成员:

ImageButton mHomeBtn; ImageButton mBackBtn; ImageButton mMenuBtn;

增加三个常量：

public static final int RESV_KEY_HOME = KeyEvent.KEYCODE_HOME;
public static final int RESV_KEY_BACK = KeyEvent.KEYCODE_BACK;
public static final int RESV_KEY_MENU = KeyEvent.KEYCODE_MENU;;

在onFinishInflate中，获取几个button 的handler，并设置touch事件，添加如下代码：

mHomeBtn = (ImageButton)findViewById(R.id.go_home); mBackBtn = (ImageButton)findViewById(R.id.go_back); mMenuBtn = (ImageButton)findViewById(R.id.pop_menu); mHomeBtn.setOnTouchListener(homeOnTouch); mBackBtn.setOnTouchListener(backOnTouch); mMenuBtn.setOnTouchListener(menuOnTouch);

各button的touch事件添加如下：

private void sendKeyIntent(int keycode){ Intent intent = new Intent(Intent.ACTION_ICONKEY_CHANGED); intent.addFlags(Intent.FLAG_RECEIVER_REGISTERED_ONLY); intent.putExtra("keycode", keycode); mService.sendIntent(intent); } private OnTouchListener homeOnTouch = new OnTouchListener(){ //@Override public boolean onTouch(View v, MotionEvent event) { // TODO Auto-generated method stub switch (event.getAction()) { case MotionEvent.ACTION_UP: { sendKeyIntent(RESV_KEY_HOME); } break; } return false; } }; private OnTouchListener backOnTouch = new OnTouchListener(){ //@Override public boolean onTouch(View v, MotionEvent event) { // TODO Auto-generated method stub switch (event.getAction()) { case MotionEvent.ACTION_UP: { sendKeyIntent(RESV_KEY_BACK); } break; } return false; } }; private OnTouchListener menuOnTouch = new OnTouchListener(){ //@Override public boolean onTouch(View v, MotionEvent event) { // TODO Auto-generated method stub switch (event.getAction()) { case MotionEvent.ACTION_UP: { sendKeyIntent(RESV_KEY_MENU); } break; } return false; } };

也就是简单的广播一个intent消息给statusBarPolicy处理。

为防止点击statusBar上的按钮， 触发标题栏的expend事件， 修改一下函数onInterceptTouchEvent，点击到不属于button区域时才允许解析Motion的event：

public boolean onInterceptTouchEvent(MotionEvent event) { if( (event.getX() > mHomeBtn.getRight()) && (event.getX() < mMenuBtn.getLeft())){ return mService.interceptTouchEvent(event) ? true : super.onInterceptTouchEvent(event); } return false; //return mService.interceptTouchEvent(event) // ? true : super.onInterceptTouchEvent(event); } }

修改StatusBarService.java，发送Intent消息需要content，这个目前只能在StatusBarService中添加一个方法：

void sendIntent(Intent intent) { mContext.sendBroadcast(intent); }

要发送intent，需要自己添加Intent：

在framework/base/core/java/android/content/intent.java中增加

@SdkConstant(SdkConstantType.BROADCAST_INTENT_ACTION) public static final String ACTION_ICONKEY_CHANGED = "android.intent.action.ICONKEY_CHANGED";

接收并处理intent， 如前篇：

接收并处理intent

这个就要修改StatusBarPolicy.java了

首先，在构造函数中加入Intent的filter，注册号这个intent的receiver。

filter.addAction(Intent.ACTION_ICONKEY_CHANGED);

然后再private BroadcastReceiver mIntentReceiver = new BroadcastReceiver() 加入Intent的receiver动作;

else if (action.equals(Intent.ACTION_ICONKEY_CHANGED)) { Log.d(TAG, "Received ACTION_ICONKEY_CHANGED"); updateIconKeyAction(intent); }

及处理函数：

private final void updateIconKeyAction(Intent intent){ int keycode = intent.getIntExtra("keycode", -1); IWindowManager wm = IWindowManager.Stub.asInterface(ServiceManager.getService("window")); if(keycode != -1){ long now = SystemClock.uptimeMillis(); KeyEvent down = new KeyEvent(now, now, KeyEvent.ACTION_DOWN, keycode, 0); KeyEvent up = new KeyEvent(now, now, KeyEvent.ACTION_UP, keycode, 0); try { wm.injectKeyEvent(down, false); }catch (RemoteException e) { Log.i("Input", "DeadOjbectException"); } try{ wm.injectKeyEvent(up, false); }catch(RemoteException e) { Log.i("Input", "DeadOjbectException"); } } }

3. StatusBar通知栏屏蔽按钮

当拉出expand的通知栏时，按钮的响应非常慢，这时最好将按钮给屏蔽掉，我们在 statusBarView.java中增加两个方法：

public void hiddenHotIcons(){ mHomeBtn.setVisibility(View.INVISIBLE); mBackBtn.setVisibility(View.INVISIBLE); mMenuBtn.setVisibility(View.INVISIBLE); } public void showHotIcons(){ mHomeBtn.setVisibility(View.VISIBLE); mBackBtn.setVisibility(View.VISIBLE); mMenuBtn.setVisibility(View.VISIBLE); }

拉出或收回通知栏中，就可以调用这个函数来显示或隐藏这几个按钮。

修改文件： statusBarService.java

void performExpand() { if (SPEW) Log.d(TAG, "performExpand: mExpanded=" + mExpanded); if ((mDisabled & StatusBarManager.DISABLE_EXPAND) != 0) { return ; } if (mExpanded) { return; } // It seems strange to sometimes not expand... if (false) { synchronized (mNotificationData) { if (mNotificationData.size() == 0) { return; } } } mExpanded = true; makeExpandedVisible(); mStatusBarView.hiddenHotIcons(); // Changed！！！ updateExpandedViewPos(EXPANDED_FULL_OPEN); if (false) postStartTracing(); } void performCollapse() { if (SPEW) Log.d(TAG, "performCollapse: mExpanded=" + mExpanded + " mExpandedVisible=" + mExpandedVisible); if (!mExpandedVisible) { return; } mExpandedVisible = false; panelSlightlyVisible(false); mExpandedParams.flags |= WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE; mExpandedParams.flags &= ~WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM; mExpandedDialog.getWindow().setAttributes(mExpandedParams); mTrackingView.setVisibility(View.GONE); mStatusBarView.showHotIcons(); // Changed！！！！ if ((mDisabled & StatusBarManager.DISABLE_NOTIFICATION_ICONS) == 0) { setNotificationIconVisibility(true, com.android.internal.R.anim.fade_in); } setDateViewVisibility(false, com.android.internal.R.anim.fade_out); if (!mExpanded) { return; } mExpanded = false; }