【Android N7.0】Framework层实现派发HOME按键到Application层的一种简单方案

frameworks/base/core/java/android/view/WindowManager.java

frameworks/base/services/core/java/com/android/server/policy/PhoneWindowManager.java

Android是不允许派发HOME按键到Application层的，其中一个原因，个人认为这是为了避免恶性软件如果同时拦截了HOME按键，BACK按键及MENU键或APP_SWITCH按键，则用户就没有办法退出Activity。因为Google保留一个HOME按键不往application层派发，可避免恶性软件的攻击。

下面介绍自己想的一种平台方实现派发HOME按键到Application层的一种简单方案，修改如下：

原文地址：http://blog.csdn.net/yelangjueqi/article/details/58587097

Framework层修改

1. WindowManager.java

......

        /**

         * Window type: disptach homekey keycent to application(Add by xxx)

         *

         * @hide

         */

        public static final int PRIVATE_FLAG_DISPATCH_HOME_KEY_TO_APP = 0x00080000;

......

2. PhoneWindowManager.java

    /** {@inheritDoc} */

    @Override

    public long interceptKeyBeforeDispatching(WindowState win, KeyEvent event, int policyFlags) {

    

        // First we always handle the home key here, so applications

        // can never break it, although if keyguard is on, we do let

        // it handle it, because that gives us the correct 5 second

        // timeout.

        if (keyCode == KeyEvent.KEYCODE_HOME) {

            WindowManager.LayoutParams attr = win != null ? win.getAttrs() : null;

            if (attr != null) {

                boolean dispatchHomeKeyToApp = (attr.privateFlags & PRIVATE_FLAG_DISPATCH_HOME_KEY_TO_APP) != 0;

                Slog.d(TAG, "dispatch homekey to application? dispatchHomeKeyToApp = " + dispatchHomeKeyToApp);

                if (dispatchHomeKeyToApp) {

                    return 0;

                }

            }

            

            // If we have released the home key, and didn't do anything else

            // while it was pressed, then it is time to go home!

        ......

        }

    }

修改截图：



3. App层使用(Activity)

    @Override

    public void onCreate(Bundle savedInstanceState) {

    

    ......

    getWindow().addPrivateFlags(WindowManager.LayoutParams.PRIVATE_FLAG_DISPATCH_HOME_KEY_TO_APP);

    }

    @Override

    public boolean dispatchKeyEvent(KeyEvent event) {

        Log.d(TAG, "dispatchKeyEvent code="+event.getKeyCode());

        switch (event.getKeyCode()) {

            case KeyEvent.KEYCODE_HOME:

                // TODO

                return true;

            default:

                break;

        }

        return super.dispatchKeyEvent(event);

    }

Log:

dispatchKeyEvent code=3

附　

基于Android N7.0制作的patch

diff --git a/core/java/android/view/WindowManager.java b/core/java/android/view/WindowManager.java
index fe24230..f7d4bc9 100644
--- a/core/java/android/view/WindowManager.java
+++ b/core/java/android/view/WindowManager.java
@@ -1254,6 +1254,13 @@ public interface WindowManager extends ViewManager {
public static final int PRIVATE_FLAG_SUSTAINED_PERFORMANCE_MODE = 0x00040000;

/**
+         * Window type: disptach homekey keycent to application
+         *
+         * @hide
+         */
+        public static final int PRIVATE_FLAG_DISPATCH_HOME_KEY_TO_APP = 0x00080000;
+
+        /**
* Control flags that are private to the platform.
* @hide
*/
diff --git a/services/core/java/com/android/server/policy/PhoneWindowManager.java b/services/core/java/com/android/server/policy/PhoneWindowManager.java
index b939fe3..c2f2a5b 100644
--- a/services/core/java/com/android/server/policy/PhoneWindowManager.java
+++ b/services/core/java/com/android/server/policy/PhoneWindowManager.java
@@ -3056,6 +3056,16 @@ public class PhoneWindowManager implements WindowManagerPolicy {
// it handle it, because that gives us the correct 5 second
// timeout.
if (keyCode == KeyEvent.KEYCODE_HOME) {
+            WindowManager.LayoutParams attr = win != null ? win.getAttrs() : null;
+            if (attr != null) {
+                boolean dispatchHomeKeyToApp = (attr.privateFlags & PRIVATE_FLAG_DISPATCH_HOME_KEY_TO_APP) != 0;
+                Slog.d(TAG, "dispatch homekey to application? dispatchHomeKeyToApp = " + dispatchHomeKeyToApp);
+                if (dispatchHomeKeyToApp) {
+                    return 0;
+                }
+            }

// If we have released the home key, and didn't do anything else
// while it was pressed, then it is time to go home!