Android控件TextView的实现原理分析
作者：网络转载 发布时间：[ 2013/5/16 10:28:29 ] 推荐标签：
接下来，我们继续分析PhoneWindow类的成员函数superDispatchKeyEvent的实现，以便可以了解键盘事件在Activity组件窗口的分发过程。
Step 8. PhoneWindow.superDispatchKeyEvent
[java] view plaincopyprint?
public class PhoneWindow extends Window implements MenuBuilder.Callback {
......
// This is the top-level view of the window， containing the window decor.
private DecorView mDecor;
......
@Override
public boolean superDispatchKeyEvent(KeyEvent event) {
return mDecor.superDispatchKeyEvent(event);
}
......
}
public class PhoneWindow extends Window implements MenuBuilder.Callback {
......
// This is the top-level view of the window， containing the window decor.
private DecorView mDecor;
......
@Override
public boolean superDispatchKeyEvent(KeyEvent event) {
return mDecor.superDispatchKeyEvent(event);
}
......
}
这个函数定义在文件frameworks/base/policy/src/com/android/internal/policy/impl/PhoneWindow.java中。
PhoneWindow类的成员变量mDecor描述的是当前正在处理的Activity组件窗口的顶层视图，PhoneWindow类的成员函数superDispatchKeyEvent通过调用它所指向的一个DecorView对象的成员函数superDispatchKeyEvent来处理参数event所描述的键盘事件。
Step 9. DecorView.superDispatchKeyEvent
[java] view plaincopyprint?
public class PhoneWindow extends Window implements MenuBuilder.Callback {
......
private final class DecorView extends FrameLayout implements RootViewSurfaceTaker {
......
public boolean superDispatchKeyEvent(KeyEvent event) {
return super.dispatchKeyEvent(event);
}
......
}
......
}
public class PhoneWindow extends Window implements MenuBuilder.Callback {
......
private final class DecorView extends FrameLayout implements RootViewSurfaceTaker {
......
public boolean superDispatchKeyEvent(KeyEvent event) {
return super.dispatchKeyEvent(event);
}
......
}
......
}
这个函数定义在文件frameworks/base/policy/src/com/android/internal/policy/impl/PhoneWindow.java中。
DecorView类的成员函数superDispatchKeyEvent的实现很简单，它只是调用父类ViewGroup的成员函数dispatchKeyEvent来处理参数event所描述的键盘事件。
sales@spasvo.com