andorid中dispatchkeyevent事件傳遞及焦點獲取

原創 life02 2018-08-28 00:01 
	DalvikVM[localhost:8601]	
		Thread [<1> main] (Suspended (breakpoint at line 740 in Workspace))	
			<VM does not provide monitor information>	
			Workspace.dispatchKeyEvent(KeyEvent) line: 740	
			FrameLayout(ViewGroup).dispatchKeyEvent(KeyEvent) line: 1246	
			FrameLayout(ViewGroup).dispatchKeyEvent(KeyEvent) line: 1246	
			FrameLayout(ViewGroup).dispatchKeyEvent(KeyEvent) line: 1246	
			LinearLayout(ViewGroup).dispatchKeyEvent(KeyEvent) line: 1246	
			PhoneWindow$DecorView(ViewGroup).dispatchKeyEvent(KeyEvent) line: 1246	
			PhoneWindow$DecorView.superDispatchKeyEvent(KeyEvent) line: 1879	
			PhoneWindow.superDispatchKeyEvent(KeyEvent) line: 1361	
			Launcher(Activity).dispatchKeyEvent(KeyEvent) line: 2324	
			Launcher.dispatchKeyEvent(KeyEvent) line: 6542	
			PhoneWindow$DecorView.dispatchKeyEvent(KeyEvent) line: 1806	
			ViewRootImpl.deliverKeyEventPostIme(KeyEvent, boolean) line: 3327	
			ViewRootImpl.handleFinishedEvent(int, boolean) line: 3300	
			ViewRootImpl.handleMessage(Message) line: 2460	
			ViewRootImpl(Handler).dispatchMessage(Message) line: 99	
			Looper.loop() line: 137	
			ActivityThread.main(String[]) line: 4429	
			Method.invokeNative(Object, Object[], Class, Class[], Class, int, boolean) line: not available [native method]	
			Method.invoke(Object, Object...) line: 511	
			ZygoteInit$MethodAndArgsCaller.run() line: 795	
			ZygoteInit.main(String[]) line: 562	
			NativeStart.main(String[]) line: not available [native method]	
		Thread [<10> Binder Thread #2] (Running)	
		Thread [<9> Binder Thread #1] (Running)	
		Daemon Thread [<8> FinalizerWatchdogDaemon] (Running)	
		Daemon Thread [<7> FinalizerDaemon] (Running)	
		Daemon Thread [<6> ReferenceQueueDaemon] (Running)	
		Daemon Thread [<11> java.lang.ProcessManager] (Running)	
		Thread [<12> launcher-loader] (Running)	
		Thread [<13> launcher-loader] (Running)	
		Thread [<15> Timer-1] (Running)	
		Thread [<14> Timer-0] (Running)	
		Thread [<18> SoundPool] (Running)	
		Thread [<19> SoundPoolThread] (Running)	
		Thread [<20> Thread-96] (Running)	
		Thread [<21> DaemonThread] (Running)	
		Thread [<17> SerialHandler] (Running)	
		Daemon Thread [<22> [email protected]@4202f9a8] (Running)	
		Thread [<25> Thread-104] (Running)	
		Thread [<26> pool-2-thread-1] (Running)	
		Thread [<28> pool-2-thread-2] (Running)	
		Thread [<29> pool-2-thread-3] (Running)	
		Thread [<30> pool-2-thread-4] (Running)	
		Thread [<31> pool-2-thread-5] (Running)	
		Thread [<32> pool-2-thread-6] (Running)	
		Thread [<33> pool-2-thread-7] (Running)	
		Thread [<34> pool-2-thread-8] (Running)	
		Thread [<35> pool-2-thread-9] (Running)	
		Thread [<36> pool-2-thread-10] (Running)	
		Thread [<16> Binder Thread #3] (Running)	
		Thread [<39> AsyncTask #5] (Running)	
		Thread [<40> AsyncTask #6] (Running)	
		Thread [<42> AsyncTask #8] (Running)	
		Thread [<44> AsyncTask #10] (Running)	
		Thread [<49> AsyncTask #15] (Running)	
		Thread [<27> Thread-149] (Running)

從以上我們可以看到事件是通過頂層view往下傳遞的

再查看viewgroup源碼

    public boolean dispatchKeyEvent(KeyEvent event) {
        if (mInputEventConsistencyVerifier != null) {
            mInputEventConsistencyVerifier.onKeyEvent(event, 1);
        }

        if ((mPrivateFlags & (FOCUSED | HAS_BOUNDS)) == (FOCUSED | HAS_BOUNDS)) {
            if (super.dispatchKeyEvent(event)) {
                return true;
            }
        } else if (mFocused != null && (mFocused.mPrivateFlags & HAS_BOUNDS) == HAS_BOUNDS) {
            if (mFocused.dispatchKeyEvent(event)) {
                return true;
            }
        }

        if (mInputEventConsistencyVerifier != null) {
            mInputEventConsistencyVerifier.onUnhandledEvent(event, 1);
        }
        return false;
    }
是從focused view往下傳遞事件


可以參考：

Android 中keyEvent的消息處理


再來按home鍵，從新獲取焦點的處理：

Home鍵
2.6_BesTVLauncherInside [Android Application]	
	DalvikVM[localhost:8601]	
		Thread [<1> main] (Suspended (breakpoint at line 50 in TintView$1))	
			<VM does not provide monitor information>	
			TintView$1.onFocusChange(View, boolean) line: 50	
			FocusView(View).onFocusChanged(boolean, int, Rect) line: 3863	
			FocusView(CusFocusView).onFocusChanged(boolean, int, Rect) line: 205	
			FocusView(View).handleFocusGainInternal(int, Rect) line: 3685	
			FocusView(View).requestFocus(int, Rect) line: 5378	
			TintView(ViewGroup).onRequestFocusInDescendants(int, Rect) line: 2154	
			TintView(ViewGroup).requestFocus(int, Rect) line: 2110	
			LinearLayout(ViewGroup).onRequestFocusInDescendants(int, Rect) line: 2154	
			LinearLayout(ViewGroup).requestFocus(int, Rect) line: 2110	
			FrameLayout(ViewGroup).onRequestFocusInDescendants(int, Rect) line: 2154	
			FrameLayout(ViewGroup).requestFocus(int, Rect) line: 2110	
			FrameLayout(ViewGroup).onRequestFocusInDescendants(int, Rect) line: 2154	
			FrameLayout(ViewGroup).requestFocus(int, Rect) line: 2110	
			FrameLayout(ViewGroup).onRequestFocusInDescendants(int, Rect) line: 2154	
			FrameLayout(ViewGroup).requestFocus(int, Rect) line: 2110	
			LinearLayout(ViewGroup).onRequestFocusInDescendants(int, Rect) line: 2154	
			LinearLayout(ViewGroup).requestFocus(int, Rect) line: 2110	
			PhoneWindow$DecorView(ViewGroup).onRequestFocusInDescendants(int, Rect) line: 2154	
			PhoneWindow$DecorView(ViewGroup).requestFocus(int, Rect) line: 2113	
			PhoneWindow$DecorView(View).requestFocus(int) line: 5328	
			ViewRootImpl.clearChildFocus(View) line: 2200	
			PhoneWindow$DecorView(ViewGroup).clearChildFocus(View) line: 669	
			LinearLayout(ViewGroup).clearChildFocus(View) line: 669	
			FrameLayout(ViewGroup).clearChildFocus(View) line: 669	
			FrameLayout(ViewGroup).clearChildFocus(View) line: 669	
			FrameLayout(ViewGroup).clearChildFocus(View) line: 669	
			Workspace(ViewGroup).clearChildFocus(View) line: 669	
			ChildLayout(ViewGroup).clearChildFocus(View) line: 669	
			CellLayout(ViewGroup).clearChildFocus(View) line: 669	
			FrameView(ViewGroup).clearChildFocus(View) line: 669	
			FrameLayout(ViewGroup).clearChildFocus(View) line: 669	
			FocusView(View).clearFocus() line: 3756	
			FrameLayout(ViewGroup).clearFocus() line: 682	
			FrameView(ViewGroup).clearFocus() line: 682	
			CellLayout(ViewGroup).clearFocus() line: 682	
			ChildLayout(ViewGroup).clearFocus() line: 682	
			Workspace.snapToScreen(int, int, boolean) line: 1448	
			Workspace.snapToScreen(int) line: 1422	
			Workspace.scrollFirst() line: 1562	
			Launcher.onNewIntent(Intent) line: 1658	
			Instrumentation.callActivityOnNewIntent(Activity, Intent) line: 1123	
			ActivityThread.deliverNewIntents(ActivityThread$ActivityClientRecord, List) line: 2042	
			ActivityThread.performNewIntents(IBinder, List) line: 2055	
			ActivityThread.handleNewIntent(ActivityThread$NewIntentData) line: 2064	
			ActivityThread.access$1400(ActivityThread, ActivityThread$NewIntentData) line: 123	
			ActivityThread$H.handleMessage(Message) line: 1194	
			ActivityThread$H(Handler).dispatchMessage(Message) line: 99	
			Looper.loop() line: 137	
			ActivityThread.main(String[]) line: 4429	
			Method.invokeNative(Object, Object[], Class, Class[], Class, int, boolean) line: not available [native method]	
			Method.invoke(Object, Object...) line: 511	
			ZygoteInit$MethodAndArgsCaller.run() line: 795	
			ZygoteInit.main(String[]) line: 562	
			NativeStart.main(String[]) line: not available [native method]	
		Thread [<10> Binder Thread #2] (Running)	
		Thread [<9> Binder Thread #1] (Running)	
		Daemon Thread [<8> FinalizerWatchdogDaemon] (Running)	
		Daemon Thread [<7> FinalizerDaemon] (Running)	
		Daemon Thread [<6> ReferenceQueueDaemon] (Running)	
		Daemon Thread [<11> java.lang.ProcessManager] (Running)	
		Thread [<12> launcher-loader] (Running)	
		Thread [<13> launcher-loader] (Running)	
		Thread [<15> Timer-1] (Running)	
		Thread [<14> Timer-0] (Running)	
		Thread [<18> SoundPool] (Running)	
		Thread [<19> SoundPoolThread] (Running)	
		Thread [<20> Thread-96] (Running)	
		Thread [<21> DaemonThread] (Running)	
		Thread [<17> SerialHandler] (Running)	
		Daemon Thread [<22> [email protected]@4202f9a8] (Running)	
		Thread [<25> Thread-104] (Running)	
		Thread [<26> pool-2-thread-1] (Running)	
		Thread [<28> pool-2-thread-2] (Running)	
		Thread [<29> pool-2-thread-3] (Running)	
		Thread [<30> pool-2-thread-4] (Running)	
		Thread [<31> pool-2-thread-5] (Running)	
		Thread [<32> pool-2-thread-6] (Running)	
		Thread [<33> pool-2-thread-7] (Running)	
		Thread [<34> pool-2-thread-8] (Running)	
		Thread [<35> pool-2-thread-9] (Running)	
		Thread [<36> pool-2-thread-10] (Running)	
		Thread [<16> Binder Thread #3] (Running)	
		Thread [<39> AsyncTask #5] (Running)	
		Thread [<40> AsyncTask #6] (Running)	
		Thread [<42> AsyncTask #8] (Running)	
		Thread [<44> AsyncTask #10] (Running)	
		Thread [<49> AsyncTask #15] (Running)


ChildLayout(ViewGroup).clearFocus() line: 682
Workspace.snapToScreen(int, int, boolean) line: 1448

調用了clearfocus

viewgroup中：

    /**
     * {@inheritDoc}
     */
    @Override
    public void clearFocus() {
        super.clearFocus();

        // clear any child focus if it exists
        if (mFocused != null) {
            mFocused.clearFocus();
        }
    }

view中： 

    public void clearFocus() {
        if (DBG) {
            System.out.println(this + " clearFocus()");
        }

        if ((mPrivateFlags & FOCUSED) != 0) {
            mPrivateFlags &= ~FOCUSED;

            if (mParent != null) {
                mParent.clearChildFocus(this);
            }

            onFocusChanged(false, 0, null);
            refreshDrawableState();
        }
    }
</pre><pre code_snippet_id="626730" snippet_file_name="blog_20150324_7_4283735" name="code" class="java"><span style="white-space:pre">		</span>
ViewRootImpl.clearChildFocus(View) line: 2200<span style="white-space:pre">	</span>

</pre>viewrootimpl中：<p></p><p></p><pre code_snippet_id="626730" snippet_file_name="blog_20150324_10_4665189" name="code" class="java">    public void clearChildFocus(View child) {
        checkThread();

        View oldFocus = mFocusedView;

        if (DEBUG_INPUT_RESIZE) Log.v(TAG, "Clearing child focus");
        mFocusedView = mRealFocusedView = null;
        if (mView != null && !mView.hasFocus()) {
            // If a view gets the focus, the listener will be invoked from requestChildFocus()
            if (!mView.requestFocus(View.FOCUS_FORWARD)) {
                mAttachInfo.mTreeObserver.dispatchOnGlobalFocusChange(oldFocus, null);
            }
        } else if (oldFocus != null) {
            mAttachInfo.mTreeObserver.dispatchOnGlobalFocusChange(oldFocus, null);
        }
    }


viewgroup中： 

<pre name="code" class="java">    protected boolean onRequestFocusInDescendants(int direction,
            Rect previouslyFocusedRect) {
        int index;
        int increment;
        int end;
        int count = mChildrenCount;
        if ((direction & FOCUS_FORWARD) != 0) {
            index = 0;
            increment = 1;
            end = count;
        } else {
            index = count - 1;
            increment = -1;
            end = -1;
        }
        final View[] children = mChildren;
        for (int i = index; i != end; i += increment) {
            View child = children[i];
            if ((child.mViewFlags & VISIBILITY_MASK) == VISIBLE) {
                if (child.requestFocus(direction, previouslyFocusedRect)) {
                    return true;
                }
            }
        }
        return false;
    }



children[i]中的第一個節點最先獲取焦點




















    





發表評論














所有評論



還沒有人評論，想成為第一個評論的人麼? 請在上方評論欄輸入並且點擊發布.







相關文章








Android開發學習二：用戶界面UI開發






《Android開發實戰 從學習到產品》李瑞琪編著 學習筆記。
用戶界面（GUI Graphics User Interface）
Android中的UI組件都繼承自android.view.View類，所有的UI組件都位於an






lit-ice

2020-07-08 11:00:42









Android開發學習三+：ListView的使用






《Android開發實戰 從學習到產品》李瑞琪編著 學習筆記
．
　　ListView是常用的組件，以列表形式展示具體內容，且能根據數據的長度自適應顯示。以垂直方式排列內部 item，item可以被定義爲各種複雜






lit-ice

2020-07-08 11:00:42









Android開發學習一：界面組件Activity






《Android開發實戰 從學習到產品》李瑞琪編著 學習筆記。
Android最常見四組件：Activity、Service、ContentProvider、BroadcastReceiver。
Activity：Android開






lit-ice

2020-07-08 11:00:42









Android開發學習三：基本控件與事件處理






《Android開發實戰 從學習到產品》李瑞琪編著 學習筆記。
一、常用基本控件的使用
1.Android常用控件類：
控件名稱
描述
控件名稱
描述
TextView
文本顯示控件
SeekBar
拖動條控件






lit-ice

2020-07-08 11:00:42









Android開發學習——之前：安裝Android Studio






Android Studio安裝配置(詳細版) Android Studio安裝配置(詳細版)






lit-ice

2020-07-08 11:00:42









OpenGL ES定義形狀






二、定義形狀
1.定義一個三角形
OpenGL ES能在3D空間中明確座標來畫出物體。要畫一個三角形，首先要定義它的座標。OpenGL中的典型作法是定義一個浮點集合代表頂點。爲了達到好的效率，將這些座標寫入ByteBuffer中，等待傳到






XliubaoX

2020-07-08 10:29:03









用android 獲取當前本地文件、文件夾，並顯示在listview上，點擊文件夾，顯示該文件夾下的文件和文件夾






1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24






XliubaoX

2020-07-08 10:29:03









推薦一款速度不錯的Android模擬器——Genymotion






特性最好的Android模擬體驗支持OpenGL加速，提供最好的3D性能體驗可以從Google Play安裝應用支持全屏並改善了使用感受全控制可同時啓動多個模擬器支持傳感器管理，如電池狀態、GPS、Accelerator加速器支持Shel






XliubaoX

2020-07-08 10:29:03









獲得一個位於屏幕底部的tabhost






即可獲得一個有三個按鈕的tabhost
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/ap






XliubaoX

2020-07-08 10:29:03









Android用SharePreference存取信息






在Android中,可以用SharePreference存取簡單的信息,例如登陸時用於記住登陸名稱與密碼等。
類的結構：android.content.SharedPreferences
下面用一個簡單的例子說明SharePreferen






XliubaoX

2020-07-08 10:29:03









Android讀寫文本文件






將一個文本文件寫入到/data/data/應用名下的files文件夾下的info.txt文件裏。
package com.example.test;
import java.io.FileNotFoundException;
imp






XliubaoX

2020-07-08 10:28:52









流轉換成字符，流轉換成字節流。stream2String,stream2Bytes






public class StreamUtil {public static String streamToString(InputStream inputStream)throws Exception {StringBuffer re






XliubaoX

2020-07-08 10:28:52









java邊讀邊寫






public class Main {public static void main(String[] args) throws IOException {// 將inputstream轉換成字符流InputStreamReader i






XliubaoX

2020-07-08 10:28:52









android調用瀏覽器網絡搜索選中文本的方法。






第一種方法：在相對佈局中加入一個webview控件，放入文字，長按文字後就能實現功能。
第二種方法：在線性佈局中加入一個線性佈局作爲父控件，一個edittext作爲文本顯示的控件。爲文本控件設置長按監聽，監聽到長按事件後，在父控件里加






XliubaoX

2020-07-08 10:28:52









Android開發ListView控件使用總結。






ListView控件是android開發中最常用的控件之一。使用過程中經常配合Adapter類使用，listview是直接與手機使用者溝通的控件；而adapter是開發者將數據展現在listview上的橋樑，根據不同的數據使用adapte






XliubaoX

2020-07-08 10:28:52