软键盘 显示隐藏 测量高度
目录
软键盘相关问题
我们在开发中经常会遇到软键盘遮挡住了输入框，而直接把输入框往上顶adjustResize这种方法过于暴力影响美观，我们希望键盘弹出时动态的去改变布局。这时候，便用到了监听键盘弹起事件的功能。
可能大家都会潜意识觉得：Android中没有可以复写的方法么？或者说，没有什么listener可以让我们使用么?
抱歉，真的没有，我们潜意识都是以为系统会提供，其实系统提供的是InputMethodManager，让我们控制键盘的弹出和隐藏，而不是键盘弹出和隐藏触发事件。
Android系统并没有给我们提供监听键盘弹出的方法，同样，Android系统也没有给我们提供获取软键盘的高度的方法，我们只能自己监听view的高度变化来间接判断键盘是不是弹出了，并通过计算获取软键盘的高度。
目前通用的方法是，由于键盘弹起与隐藏，会使得layout的布局发生变化，通过布局的大小变化触发的事件实现键盘事件的触发。
设置 OnLayoutChangeListener - 推荐
不要忘了设置键盘
android:windowSoftInputMode="stateAlwaysHidden|adjustResize"
使用
public class MainActivity extends Activity {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.edit);
int scrollHeight = getWindowManager().getDefaultDisplay().getHeight() / 4;
findViewById(android.R.id.content).addOnLayoutChangeListener((v, left, top, right, bottom, oldLeft, oldTop, oldRight, oldBottom) -> {
if (oldBottom != 0 && bottom != 0) {
int softInputHeight = oldBottom - bottom;//这个就是键盘高度
Log.i("bqt", "【键盘高度】" + Math.abs(softInputHeight));
if (softInputHeight > scrollHeight) {
Toast.makeText(MainActivity.this, "键盘弹起", Toast.LENGTH_SHORT).show();
} else if (Math.abs(softInputHeight) > scrollHeight) {
Toast.makeText(MainActivity.this, "键盘落下", Toast.LENGTH_SHORT).show();
}
}
});
}
}
设置 OnGlobalLayoutListener - 推荐
不要忘了设置键盘
android:windowSoftInputMode="stateAlwaysHidden|adjustResize"
使用
public class MainActivity extends Activity {
private int keyboardHeight;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.edit);
new KeyboardChangeListener(this).setKeyBoardListener((isShow, keyboardCurrentHeight) -> {
Log.i("bqt", "【当前键盘的高度】" + keyboardCurrentHeight);//注意，这里返回的直接是键盘的高度，键盘隐藏时高度为0
if (isShow) {
this.keyboardHeight = keyboardCurrentHeight;
Log.i("bqt", "【键盘的高度】" + keyboardHeight);
Toast.makeText(MainActivity.this, "键盘弹起", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(MainActivity.this, "键盘隐藏", Toast.LENGTH_SHORT).show();
}
});
}
}
KeyboardChangeListener
public class KeyboardChangeListener implements ViewTreeObserver.OnGlobalLayoutListener {
private static final String TAG = "bqt";
private View mContentView;
private int mOriginHeight;
private int mPreHeight;
private KeyBoardListener mKeyBoardListen;
public interface KeyBoardListener {
/**
* call back
*
* @param isShow true is show else hidden
* @param keyboardHeight keyboard height
*/
void onKeyboardChange(boolean isShow, int keyboardHeight);
}
public void setKeyBoardListener(KeyBoardListener keyBoardListen) {
this.mKeyBoardListen = keyBoardListen;
}
public KeyboardChangeListener(Activity contextObj) {
if (contextObj == null) {
Log.i(TAG, "contextObj is null");
return;
}
mContentView = findContentView(contextObj);
if (mContentView != null) {
addContentTreeObserver();
}
}
private View findContentView(Activity contextObj) {
return contextObj.findViewById(android.R.id.content);
}
private void addContentTreeObserver() {
mContentView.getViewTreeObserver().addOnGlobalLayoutListener(this);
}
@Override
public void onGlobalLayout() {
int currHeight = mContentView.getHeight();
if (currHeight == 0) {
Log.i(TAG, "currHeight is 0");
return;
}
boolean hasChange = false;
if (mPreHeight == 0) {
mPreHeight = currHeight;
mOriginHeight = currHeight;
} else {
if (mPreHeight != currHeight) {
hasChange = true;
mPreHeight = currHeight;
} else {
hasChange = false;
}
}
if (hasChange) {
boolean isShow;
int keyboardHeight = 0;
if (mOriginHeight == currHeight) {
//hidden
isShow = false;
} else {
//show
keyboardHeight = mOriginHeight - currHeight;
isShow = true;
}
if (mKeyBoardListen != null) {
mKeyBoardListen.onKeyboardChange(isShow, keyboardHeight);
}
}
}
@SuppressLint("ObsoleteSdkInt")
public void destroy() {
if (mContentView != null) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
mContentView.getViewTreeObserver().removeOnGlobalLayoutListener(this);
}
}
}
}
重写 onSizeChanged - 麻烦，不推荐
不要忘了设置键盘
android:windowSoftInputMode="stateAlwaysHidden|adjustResize"
使用
public class MainActivity extends Activity {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.edit);
AdjustSizeRelativeLayout layout = findViewById(R.id.rl_root);
layout.setSoftKeyBoardListener(new AdjustSizeRelativeLayout.SoftkeyBoardListener() {
@Override
public void keyBoardVisable(int move) {
Toast.makeText(MainActivity.this, "键盘弹起，高度：" + move, Toast.LENGTH_SHORT).show();
}
@Override
public void keyBoardInvisable(int move) {
Toast.makeText(MainActivity.this, "键盘隐藏，高度：" + move, Toast.LENGTH_SHORT).show();
}
});
}
}
布局
<?xml version="1.0" encoding="utf-8"?>
<com.bqt.test.AdjustSizeRelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/rl_root"
android:layout_width="match_parent"
android:layout_height="match_parent">
<EditText
android:layout_width="match_parent"
android:layout_height="44dp"
android:layout_alignParentBottom="true"
android:hint="输入交易密码"
android:inputType="text"
android:paddingLeft="5dp"/>
</com.bqt.test.AdjustSizeRelativeLayout>
自定义的ViewGroup
public class AdjustSizeRelativeLayout extends RelativeLayout {
public AdjustSizeRelativeLayout(Context context) {
super(context);
}
public AdjustSizeRelativeLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public AdjustSizeRelativeLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
private static final int CHANGE_SIZE = 200;
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
Log.i("bqt", "【onSizeChanged】" + w + " " + h + " " + oldw + " " + oldh);
if (oldw == 0 || oldh == 0) return;
if (boardListener != null) {
if (h - oldh < -CHANGE_SIZE) {
Log.i("bqt", "键盘弹出" + "change" + w + " " + h + " " + oldw + " " + oldh);
boardListener.keyBoardVisable(Math.abs(h - oldh));
}
if (h - oldh > CHANGE_SIZE) {
Log.i("bqt", "键盘结束" + "change" + w + " " + h + " " + oldw + " " + oldh);
boardListener.keyBoardInvisable(Math.abs(h - oldh));
}
}
}
public interface SoftkeyBoardListener {
public void keyBoardVisable(int move);
public void keyBoardInvisable(int move);
}
private SoftkeyBoardListener boardListener;
public void setSoftKeyBoardListener(SoftkeyBoardListener boardListener) {
this.boardListener = boardListener;
}
}
2018-5-21
本文来自博客园，作者：白乾涛，转载请注明原文链接：https://www.cnblogs.com/baiqiantao/p/9066136.html
