Android软键盘的显示隐藏功能实现过程

public class ResizeLayout extends LinearLayout{ 
  private static int count = 0; 
   
  public ResizeLayout(Context context, AttributeSet attrs) { 
    super(context, attrs); 
  } 
   
  @Override 
  protected void onSizeChanged(int w, int h, int oldw, int oldh) {   
    super.onSizeChanged(w, h, oldw, oldh); 
     
    Log.e("onSizeChanged " + count++, "=>onResize called! w="+w + ",h="+h+",oldw="+oldw+",oldh="+oldh); 
  } 
   
  @Override 
  protected void onLayout(boolean changed, int l, int t, int r, int b) { 
    super.onLayout(changed, l, t, r, b); 
    Log.e("onLayout " + count++, "=>OnLayout called! l=" + l + ", t=" + t + ",r=" + r + ",b="+b); 
  } 
   
  @Override 
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 
    super.onMeasure(widthMeasureSpec, heightMeasureSpec); 
     
    Log.e("onMeasure " + count++, "=>onMeasure called! widthMeasureSpec=" + widthMeasureSpec + ", heightMeasureSpec=" + heightMeasureSpec); 
  } 

<com.winuxxan.inputMethodTest.ResizeLayout 
 xmlns:android="http://schemas.android.com/apk/res/android" 
 android:id="@+id/root_layout" 
 android:layout_width="fill_parent" 
 android:layout_height="fill_parent" 
 android:orientation="vertical" 
 > 
 <EditText 
  android:layout_width="fill_parent" 
  android:layout_height="wrap_content" 
 /> 
 <LinearLayout 
   android:id="@+id/bottom_layout" 
   android:layout_width="fill_parent" 
   android:layout_height="fill_parent" 
   android:orientation="vertical" 
   android:gravity="bottom">s 
 <TextView 
  android:layout_width="fill_parent" 
  android:layout_height="wrap_content" 
  android:text="@string/hello" 
  android:background="#77777777" 
  /> 
 </LinearLayout> 
</com.winuxxan.inputMethodTest.ResizeLayout> 

E/onMeasure 6(7960): =>onMeasure called! widthMeasureSpec=1073742144, heightMeasureSpec = 1073742024
E/onMeasure 7(7960): =>onMeasure called! widthMeasureSpec=1073742144, heightMeasureSpec = 1073742025
E/onSizeChanged 8(7960): =>onSizeChanged called! w=320,h=201,oldw=320,oldh=377
E/onLayout 9(7960): =>OnLayout called! l=0, t=0,r=320,b=201

E/onMeasure 6(8378): =>onMeasure called! widthMeasureSpec=1073742144, heightMeasureSpec=1073742200
E/onMeasure 7(8378): =>onMeasure called! widthMeasureSpec=1073742144, heightMeasureSpec=1073742201
E/onLayout 8(8378): =>OnLayout called! l=0, t=0,r=320,b=377