getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_PAN);

android:windowSoftInputMode="stateVisible|adjustResize" 

<activity android:windowSoftInputMode="stateVisible|adjustResize". . . >

<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent" android:layout_height="fill_parent">
<LinearLayout android:layout_width="fill_parent"
android:layout_height="fill_parent" android:orientation="vertical">
</LinearLayout>
</ScrollView>

<com.jereh.overidelinearlayout.LinearLayoutView xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
android:id="@+id/login_root_layout"
android:layout_height="match_parent"
android:orientation="vertical">
<!—这里模仿一个登录界面-->
<LinearLayout
android:id="@+id/login_layout_logo"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="10"
android:background="#ff0000"
android:orientation="vertical" >
<ImageView
android:id="@+id/textView1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:src="@drawable/login_logo"
android:scaleType="fitXY"/>
</LinearLayout>
<!—输入框和密码框-->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_marginTop="20dp"
android:layout_weight="3"
android:orientation="vertical" >
<EditText
android:id="@+id/editText1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/textView1"
android:layout_alignParentBottom="true"
android:layout_gravity="center_vertical"
android:hint="用户名"
android:ems="10" >
<requestFocus />
</EditText>
<EditText
android:id="@+id/editText1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/textView1"
android:layout_alignParentBottom="true"
android:layout_gravity="center_vertical"
android:hint="密码"
android:ems="10" >
<requestFocus />
</EditText>
</LinearLayout>
</com.jereh.overidelinearlayout.LinearLayoutView>

protected void onSizeChanged(int w,final int h, int oldw,final int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
uiHandler.post(new Runnable() {
public void run() {
if (oldh - h > SOFTKEYPAD_MIN_HEIGHT){ // 软键盘关闭
keyBordStateListener.stateChange(KEYBORAD_SHOW);//回调方法显示部分区域
}else { // 软键盘弹出 
if(keyBordStateListener != null){
keyBordStateListener.stateChange(KEYBORAD_HIDE);// 回调方法隐藏部分区域
}
}
}
});
}

public interface KeyBordStateListener{ public void stateChange(int state);}//定义接口
private KeyBordStateListener keyBordStateListener;
public void setKeyBordStateListener(KeyBordStateListener keyBordStateListener) {
this.keyBordStateListener = keyBordStateListener;
}
LinearLayoutView组件的完整代码：
public class LinearLayoutView extends LinearLayout{
public static final int KEYBORAD_HIDE = 0;
public static final int KEYBORAD_SHOW = 1;
private static final int SOFTKEYPAD_MIN_HEIGHT = 50;
private Handler uiHandler = new Handler();
public LinearLayoutView(Context context) {
super(context);
}
public LinearLayoutView(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onSizeChanged(int w,final int h, int oldw,final int oldh) {
// TODO Auto-generated method stub
super.onSizeChanged(w, h, oldw, oldh);
uiHandler.post(new Runnable() {
@Override
public void run() {
if (oldh - h > SOFTKEYPAD_MIN_HEIGHT){ 
keyBordStateListener.stateChange(KEYBORAD_SHOW);
}else { 
if(keyBordStateListener != null){
keyBordStateListener.stateChange(KEYBORAD_HIDE);}
}
}
});
}
private KeyBordStateListener keyBordStateListener;
public void 、setKeyBordStateListener(KeyBordStateListener keyBordStateListener) {
this.keyBordStateListener = keyBordStateListener;
}
public interface KeyBordStateListener{ 
public void stateChange(int state);
}

public class MainActivity extends Activity implements KeyBordStateListener {
private LinearLayoutView resizeLayout;
private LinearLayout logoLayout;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//获得可根据软键盘的弹出/关闭而隐藏和显示某些区域的LinearLayoutView组件 
resizeLayout = (LinearLayoutView) findViewById(R.id.login_root_layout);
//获得要控制隐藏和显示的区域
logoLayout = (LinearLayout) findViewById(R.id.login_layout_logo);
resizeLayout.setKeyBordStateListener(this);//设置回调方法
}
//实现接口中的方法，该方法在resizeLayout的onSizeChanged方法中调用
@Override
public void stateChange(int state) {
// TODO Auto-generated method stub
switch (state) {
case LinearLayoutView.KEYBORAD_HIDE:
logoLayout.setVisibility(View.VISIBLE);
break;
case LinearLayoutView.KEYBORAD_SHOW:
logoLayout.setVisibility(View.GONE);
break;
}
}