引言
今天我們主要講的是SystemUI狀態欄里面常見的一排icons——status icons,該icons主要用于顯示Bluetooth、Location、Headset等等系統狀態的icon,表示當前手機藍牙、定位、耳機等的功能開啟了,以達到提示用戶的目的。
正文
本文主要從兩個方面講述下status icon功能,主要分為初始化流程和狀態顯示流程
話不多說,我們開始吧。
初始化流程
首先我們看下狀態欄的布局文件 status_bar.xml
<com.android.keyguard.AlphaOptimizedLinearLayout android:id="@+id/system_icon_area"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal"
>
<include layout="@layout/system_icons" />
<com.android.systemui.statusbar.policy.Clock
android:id="@+id/clock"
android:textAppearance="@style/TextAppearance.StatusBar.Clock"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:singleLine="true"
android:paddingStart="@dimen/status_bar_clock_starting_padding"
android:paddingEnd="@dimen/status_bar_clock_end_padding"
android:gravity="center_vertical|start"
/>
</com.android.keyguard.AlphaOptimizedLinearLayout>
其中我們今天講的status_icons就藏身于 system_icons.xml 之中
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/system_icons"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:gravity="center_vertical">
<com.android.keyguard.AlphaOptimizedLinearLayout android:id="@+id/statusIcons"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:gravity="center_vertical"
android:orientation="horizontal"/>
<include layout="@layout/signal_cluster_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="@dimen/signal_cluster_margin_start"/>
<com.android.systemui.BatteryMeterView android:id="@+id/battery"
android:layout_height="match_parent"
android:layout_width="wrap_content"
/>
</LinearLayout>
android:id="@+id/statusIcons"出現了,人如其名,它其實是一個自定義的LinearLayout——AlphaOptimizedLinearLayout,這個Viewt也是非常簡單的,只是實現了如下方法
@Override
public boolean hasOverlappingRendering() {
return false;
}
該方法用來標記當前view是否存在過度繪制,存在返回ture,不存在返回false,而api里面默認返回為true,誠然我們status icon是個好同學,不存在過度繪制。
接下來我們看下SystemUI是怎么加載這個AlphaOptimizedLinearLayout
@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
mStatusBar = (PhoneStatusBarView) view;
if (savedInstanceState != null && savedInstanceState.containsKey(EXTRA_PANEL_STATE)) {
mStatusBar.go(savedInstanceState.getInt(EXTRA_PANEL_STATE));
}
mDarkIconManager = new DarkIconManager(view.findViewById(R.id.statusIcons));
Dependency.get(StatusBarIconController.class).addIconGroup(mDarkIconManager);
mSystemIconArea = mStatusBar.findViewById(R.id.system_icon_area);
mSignalClusterView = mStatusBar.findViewById(R.id.signal_cluster);
Dependency.get(DarkIconDispatcher.class).addDarkReceiver(mSignalClusterView);
// Default to showing until we know otherwise.
showSystemIconArea(false);
initEmergencyCryptkeeperText();
}
在 CollapsedStatusBarFragment.java 中我們見到了初始化,這個類相信有狀態欄開發經驗的都很熟悉了,與本文相關的代碼如下
mDarkIconManager = new DarkIconManager(view.findViewById(R.id.statusIcons));
我們接著看這個DarkIconManager初始化里做了什么
public DarkIconManager(LinearLayout linearLayout) {
super(linearLayout);
mIconHPadding = mContext.getResources().getDimensionPixelSize(
R.dimen.status_bar_icon_padding);
mDarkIconDispatcher = Dependency.get(DarkIconDispatcher.class);
}
public static class IconManager {
protected final ViewGroup mGroup;
protected final Context mContext;
protected final int mIconSize;
public IconManager(ViewGroup group) {
mGroup = group;
mContext = group.getContext();
mIconSize = mContext.getResources().getDimensionPixelSize(
com.android.internal.R.dimen.status_bar_icon_size);
}
protected void onIconAdded(int index, String slot, boolean blocked,
StatusBarIcon icon) {
addIcon(index, slot, blocked, icon);
}
protected StatusBarIconView addIcon(int index, String slot, boolean blocked,
StatusBarIcon icon) {
StatusBarIconView view = onCreateStatusBarIconView(slot, blocked);
view.set(icon);
mGroup.addView(view, index, onCreateLayoutParams());
return view;
}
public void onSetIcon(int viewIndex, StatusBarIcon icon) {
StatusBarIconView view = (StatusBarIconView) mGroup.getChildAt(viewIndex);
view.set(icon);
}
}
在StatusBarIconController.java中可以看到,在onIconAdded--->addIcon兩個函數里面實現了AlphaOptimizedLinearLayout子view即icon的增加,onSetIcon可能就是刷新icon狀態的,請記住這兩張面孔
onIconAdded(int index, String slot, boolean blocked,StatusBarIcon icon)
onSetIcon(int viewIndex, StatusBarIcon icon)
到這里我們就知道了icon添加的流程。
onIconAdded(int index, String slot, boolean blocked,StatusBarIcon icon)
而且在這個函數里面有參數index和slot,我們應該可以猜到,每個icon應該就是對應著代表順序的index和數據類型為String的slot,那么到底是不是這樣呢?index和slot又是從哪里來的呢?我們接著往下看。
在StatusBarIconControllerImpl.java構造函數里我們找到了實現
public StatusBarIconControllerImpl(Context context) {
super(context.getResources().getStringArray(
com.android.internal.R.array.config_statusBarIcons));
StatusBarIconControllerImpl的父類是StatusBarIconList
protected ArrayList<String> mSlots = new ArrayList<>();
protected ArrayList<StatusBarIcon> mIcons = new ArrayList<>();
public StatusBarIconList(String[] slots) {
final int N = slots.length;
for (int i=0; i < N; i++) {
mSlots.add(slots[i]);
mIcons.add(null);
}
}
在這里我們就找到了index和slot的出處,原來在初始化的時候就已經定義好了所有的slots,然后從framework中加載出來,index就是string-array中的順序。
<string-array name="config_statusBarIcons">
<item><xliff:g id="id">@string/status_bar_rotate</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_headset</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_data_saver</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_managed_profile</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_ime</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_sync_failing</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_sync_active</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_cast</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_hotspot</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_location</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_bluetooth</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_nfc</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_tty</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_speakerphone</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_zen</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_mute</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_volume</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_vpn</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_ethernet</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_wifi</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_mobile</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_airplane</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_cdma_eri</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_data_connection</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_phone_evdo_signal</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_phone_signal</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_battery</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_alarm_clock</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_secure</xliff:g></item>
<item><xliff:g id="id">@string/status_bar_clock</xliff:g></item>
</string-array>
<string translatable="false" name="status_bar_rotate">rotate</string>
<string translatable="false" name="status_bar_headset">headset</string>
<string translatable="false" name="status_bar_data_saver">data_saver</string>
<string translatable="false" name="status_bar_managed_profile">managed_profile</string>
<string translatable="false" name="status_bar_ime">ime</string>
<string translatable="false" name="status_bar_sync_failing">sync_failing</string>
<string translatable="false" name="status_bar_sync_active">sync_active</string>
<string translatable="false" name="status_bar_cast">cast</string>
<string translatable="false" name="status_bar_hotspot">hotspot</string>
<string translatable="false" name="status_bar_location">location</string>
<string translatable="false" name="status_bar_bluetooth">bluetooth</string>
<string translatable="false" name="status_bar_nfc">nfc</string>
<string translatable="false" name="status_bar_tty">tty</string>
<string translatable="false" name="status_bar_speakerphone">speakerphone</string>
<string translatable="false" name="status_bar_zen">zen</string>
<string translatable="false" name="status_bar_mute">mute</string>
<string translatable="false" name="status_bar_volume">volume</string>
<string translatable="false" name="status_bar_wifi">wifi</string>
<string translatable="false" name="status_bar_cdma_eri">cdma_eri</string>
<string translatable="false" name="status_bar_data_connection">data_connection</string>
<string translatable="false" name="status_bar_phone_evdo_signal">phone_evdo_signal</string>
<string translatable="false" name="status_bar_phone_signal">phone_signal</string>
<string translatable="false" name="status_bar_battery">battery</string>
<string translatable="false" name="status_bar_alarm_clock">alarm_clock</string>
<string translatable="false" name="status_bar_secure">secure</string>
<string translatable="false" name="status_bar_clock">clock</string>
<string translatable="false" name="status_bar_mobile">mobile</string>
<string translatable="false" name="status_bar_vpn">vpn</string>
<string translatable="false" name="status_bar_ethernet">ethernet</string>
<string translatable="false" name="status_bar_airplane">airplane</string>
好了,到這里我們的第一部分初始化流程就講完了
狀態顯示流程
由上面的初始化流程我們可以知道,每個icon都對應了slot,slot數量比較多,我們就挑一個常見的Headset講下,其他的流程都是大致一樣的。
PhoneStatusBarPolicy.java這個類在初始化的時候注冊了大量的監聽
public PhoneStatusBarPolicy(Context context, StatusBarIconController iconController) {
mContext = context;
// 初始化headset的slot
mSlotHeadset = context.getString(com.android.internal.R.string.status_bar_headset);
// listen for broadcasts
IntentFilter filter = new IntentFilter();
filter.addAction(AudioManager.RINGER_MODE_CHANGED_ACTION);
filter.addAction(AudioManager.INTERNAL_RINGER_MODE_CHANGED_ACTION);
// 注冊headset狀態變化的action
filter.addAction(AudioManager.ACTION_HEADSET_PLUG);
filter.addAction(TelephonyIntents.ACTION_SIM_STATE_CHANGED);
filter.addAction(TelecomManager.ACTION_CURRENT_TTY_MODE_CHANGED);
filter.addAction(Intent.ACTION_MANAGED_PROFILE_AVAILABLE);
filter.addAction(Intent.ACTION_MANAGED_PROFILE_UNAVAILABLE);
filter.addAction(Intent.ACTION_MANAGED_PROFILE_REMOVED);
mContext.registerReceiver(mIntentReceiver, filter, null, mHandler);
這個類就是完成icon添加和狀態監聽的地方,然后當收到對應的action變化的時候,更新headset icon
private void updateHeadsetPlug(Intent intent) {
boolean connected = intent.getIntExtra("state", 0) != 0;
boolean hasMic = intent.getIntExtra("microphone", 0) != 0;
if (connected) {
String contentDescription = mContext.getString(hasMic
? R.string.accessibility_status_bar_headset
: R.string.accessibility_status_bar_headphones);
mIconController.setIcon(mSlotHeadset, hasMic ? R.drawable.ic_headset_mic
: R.drawable.ic_headset, contentDescription);
mIconController.setIconVisibility(mSlotHeadset, true);
} else {
mIconController.setIconVisibility(mSlotHeadset, false);
}
}
其中主要的方法如下
mIconController.setIcon(mSlotHeadset, hasMic ? R.drawable.ic_headset_mic
: R.drawable.ic_headset, contentDescription);
mIconController.setIconVisibility(mSlotHeadset, true);
這兩個函數里面setIcon負責設置icon,而setIconVisibility則根據connected狀態設置icon的可見性,下面我們就看下這里面的流程是怎么和初始化流程連接在一起的。
來到StatusBarIconControllerImpl.java這個類中的實現
@Override
public void setIcon(String slot, int resourceId, CharSequence contentDescription) {
int index = getSlotIndex(slot);
StatusBarIcon icon = getIcon(index);
if (icon == null) {
icon = new StatusBarIcon(UserHandle.SYSTEM, mContext.getPackageName(),
Icon.createWithResource(mContext, resourceId), 0, 0, contentDescription);
setIcon(slot, icon);
} else {
icon.icon = Icon.createWithResource(mContext, resourceId);
icon.contentDescription = contentDescription;
handleSet(index, icon);
}
}
邏輯很清晰,首先根據slot找到對應的index,然后用index取得對應的icon,誠然第一次的時候,icon == null,所以通過new StatusBarIcon創建一個,然后調用 setIcon(slot, icon),我們接著往下看
@Override
public void setIcon(String slot, StatusBarIcon icon) {
setIcon(getSlotIndex(slot), icon);
}
@Override
public void setIcon(int index, StatusBarIcon icon) {
if (icon == null) {
removeIcon(index);
return;
}
boolean isNew = getIcon(index) == null;
super.setIcon(index, icon);
if (isNew) {
addSystemIcon(index, icon);
} else {
handleSet(index, icon);
}
}
因為我們之前已經添加了icon,此處icon非空,所以不會走return,但是我們剛才getIcon(index) == null的,所以主要看的是addSystemIcon(index, icon)方法
private void addSystemIcon(int index, StatusBarIcon icon) {
String slot = getSlot(index);
int viewIndex = getViewIndex(index);
boolean blocked = mIconBlacklist.contains(slot);
mIconLogger.onIconVisibility(getSlot(index), icon.visible);
mIconGroups.forEach(l -> l.onIconAdded(viewIndex, slot, blocked, icon));
}
有沒有看到一個熟悉的面孔——onIconAdded,對了這個就是我們初始化流程里面StatusBarIconController中添加icon的入口,好了到這里setIcon就添加完畢了。
接著就是setIconVisibility函數了,我們再回到StatusBarIconControllerImpl.java中
public void setIconVisibility(String slot, boolean visibility) {
int index = getSlotIndex(slot);
StatusBarIcon icon = getIcon(index);
if (icon == null || icon.visible == visibility) {
return;
}
icon.visible = visibility;
handleSet(index, icon);
}
icon已經創建成功了,icon非空,并且第一次是icon.visible != visibility的,自然就會順利的走到handleSet(index, icon)
private void handleSet(int index, StatusBarIcon icon) {
int viewIndex = getViewIndex(index);
mIconLogger.onIconVisibility(getSlot(index), icon.visible);
mIconGroups.forEach(l -> l.onSetIcon(viewIndex, icon));
}
好了又是一個熟悉的面孔——onSetIcon,這個也是我們初始化流程里面StatusBarIconController中setIcon的地方,setIconVisibility也設置完畢了。
到這里,status icon加載流程已經講完,后面有時間還會講下notification icon和signal icon的加載流程,敬請關注。
如有什么問題歡迎指正。
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