Android手机软键盘掩饰输入框之重新布局详解_Android

Android手机软键盘遮盖输入框之重新布局详解

问题

?????? 在开发Android应用程序时，经常会有登录界面，无非是输入用户名、密码进行登录。当输入框获取焦点时，会弹出软键盘进行输入，如果输入框和登录按钮布局在整个布局文件的中间或靠下，势必会被软键盘遮挡，让人十分郁闷。网络上的解决方法无非也就那么三种：

第一、将登录框放在布局文件的顶端，软键盘不会遮挡；这种方案虽然能解决问题，但相当不灵活；

第二、在布局文件中根节点处加入ScrollView控件；

第三、这是我今天要讲的内容

首先，继承RelativeLayout，获取当前屏幕高度，实现onMesure、onSizeChanged方法；

其次，为自定义的Layout添加视图偏移的监听器

最后、在Activity当中实现监听

代码

[java]?view plaincopy?
public?class?InputMethodRelativeLayout?extends?RelativeLayout?{??
????private?int?width;??
??????
????private?int?height;??
??????
????private?int?screenHeight;??
??????
????private?boolean?sizeChanged?=?false;??
??????
????private?OnSizeChangedListener?onSizeChangedListener;??
??????
????public?InputMethodRelativeLayout(Context?context,?AttributeSet?attrs,??
????????????int?defStyle)?{??
????????super(context,?attrs,?defStyle);??
????????Display?localDisplay?=?((Activity)context).getWindowManager().getDefaultDisplay();??
????????screenHeight?=?localDisplay.getHeight();??
????????//?TODO?Auto-generated?constructor?stub??
????}??
??
????public?InputMethodRelativeLayout(Context?context,?AttributeSet?attrs)?{??
????????super(context,?attrs);??
????????//?TODO?Auto-generated?constructor?stub??
????}??
??
????public?InputMethodRelativeLayout(Context?context)?{??
????????super(context);??
????????//?TODO?Auto-generated?constructor?stub??
????}??
??
????@Override??
????protected?void?onMeasure(int?widthMeasureSpec,?int?heightMeasureSpec)?{??
????????//?TODO?Auto-generated?method?stub??
????????this.width?=?widthMeasureSpec;??
????????this.height?=?heightMeasureSpec;??
????????super.onMeasure(widthMeasureSpec,?heightMeasureSpec);??
????}??
??
????@Override??
????protected?void?onSizeChanged(int?w,?int?h,?int?oldw,?int?oldh)?{??
????????//?TODO?Auto-generated?method?stub??

[java]?view plaincopy?
//监听不为空、宽度不变、当前高度与历史高度不为0??
if(this.onSizeChangedListener?!=?null?&&?w?==?oldw?&&?h?!=?0?&&?oldh?!=?0){??

[java]?view plaincopy?
????????if(h?>=?oldh?||?(Math.abs(h?-?oldh)?<=?1?*?this.screenHeight?/?4)){??
????????????sizeChanged?=?false;??
????????}else?if(h?<=?oldh?||?(Math.abs(h?-?oldh)?<=?1?*?this.screenHeight?/?4)){??
????????????sizeChanged?=?true;??
????????}??
????????this.onSizeChangedListener.onSizeChange(sizeChanged);??
????????measure(this.width?-?w?+?getWidth(),?this.height?-?h?+?getHeight());??
????}??
}??
??
/**??
[email protected]:?setOnSizeChangedListener??
[email protected]:?为当前布局设置onSizeChanged监听器??
[email protected]?
[email protected]?
*/???
public?void?setOnSizeChangedListener(OnSizeChangedListener?sizeChangedListener)?{??
????this.onSizeChangedListener?=?sizeChangedListener;??
}??
??
??
public?abstract?interface?OnSizeChangedListener{??
??????
????public?abstract?void?onSizeChange(boolean?flag);??
}??

在Activity中实现OnSizeChangedListener，原理是设置该布局的paddingTop属性来控制子View的偏移，如下：

[java]?view plaincopy?
public?class?OALogin?extends?BaseActivity?implements?InputMethodRelativeLayout.OnSizeChangedListener{??
??????
????@InjectView(R.id.loginpage)??
????private?InputMethodRelativeLayout?layout;??
??????
????@Inject??
????private?InputMethodManager?inputMethodManager;??
????private?float?density;??
????@Override??
????protected?void?onCreate(Bundle?savedInstanceState)?{??
????????//?TODO?Auto-generated?method?stub??
????????super.onCreate(savedInstanceState);??
????????setContentView(R.layout.login_page);??
????????getSupportActionBar().hide();??
????????density?=?getResources().getDisplayMetrics().density;??
????????layout.setOnSizeChangedListener(this);??
????}??
??
????@Override??
????public?void?onSizeChange(boolean?flag)?{??
????????//?TODO?Auto-generated?method?stub??
????????if(flag){??
????????????layout.setPadding(0,?-159,?0,?0);??
????????}else??
????????????layout.setPadding(0,?0,?0,?0);??
????}??
??
????@Override??
????public?boolean?onTouchEvent(MotionEvent?event)?{??
????????//?TODO?Auto-generated?method?stub??
????????if(event.getAction()?==?MotionEvent.ACTION_UP){??
????????????inputMethodManager.hideSoftInputFromWindow(getWindow().getDecorView().getWindowToken(),0);??
????????}??
????????return?super.onTouchEvent(event);??
????}??

在AndroidManifest.xml中注册该Activity，需要注意的是：必须为该Activity设置android:windowSoftInputMode="adjustResize"属性，当windowSoftInputMode为adjustResiz时，Layout才会调用protected void onSizeChanged(int w, int h, int oldw, int oldh)这个方法。

俗话说，无图无真相，直接上图（借助了QQ2012的登录界面）

各位体会下吧！