Android软键盘的打开和关闭的监控

最近客户出了一个很变态的需求：当客户在输入框输入内容后，关闭软键盘的时候刷新数据。我去，旁边加个Button按钮就很轻松的问题，搞这么复杂。没思路，找度娘寻思路：
准照度娘的开发经验，搞了一个Demo，可以用了，具体如下：
Demo的xml文件：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout  xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/activity_main_layout" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" android:gravity="center_horizontal" tools:context="com.haoyue.notedemos.input.InputDialogActivity">
    <EditText  android:id="@+id/etListener" android:layout_width="match_parent" android:layout_height="60dp" android:layout_margin="20dp" android:background="@drawable/edittext_bc" android:hint="InputText" android:textColorHint="#00bb33" android:paddingLeft="10dp"/>
</LinearLayout>

Activity代码：

public class InputDialogActivity extends BaseActivity {
    @BindView(R.id.etListener)
    EditText mEtListener;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_input_dialog);
        ButterKnife.bind(this);
        setListenerFotEditText(findViewById(R.id.activity_main_layout));
    }
    private void setListenerFotEditText(View view){
        SoftKeyboardStateHelper softKeyboardStateHelper = new SoftKeyboardStateHelper(view);
        softKeyboardStateHelper.addSoftKeyboardStateListener(new SoftKeyboardStateHelper.SoftKeyboardStateListener() {
            @Override
            public void onSoftKeyboardOpened(int keyboardHeightInPx) {
                //键盘打开
                Toast.makeText(InputDialogActivity.this, mEtListener.getText().toString() + "打开", Toast.LENGTH_SHORT).show();
            }

            @Override
            public void onSoftKeyboardClosed() {
                //键盘关闭
                Toast.makeText(InputDialogActivity.this, mEtListener.getText().toString() + "关闭", Toast.LENGTH_SHORT).show();
            }
        });
    }
}

SoftKeyboardStateHelper帮助类文件如下：

public class SoftKeyboardStateHelper implements ViewTreeObserver.OnGlobalLayoutListener {
    public interface SoftKeyboardStateListener {
        void onSoftKeyboardOpened(int keyboardHeightInPx);
        void onSoftKeyboardClosed();
    }

    private final List<SoftKeyboardStateListener> listeners = new LinkedList<SoftKeyboardStateListener>();
    private final View activityRootView;
    private int lastSoftKeyboardHeightInPx;
    private boolean isSoftKeyboardOpened;

    public SoftKeyboardStateHelper(View activityRootView) {
        this(activityRootView, false);
    }

    public SoftKeyboardStateHelper(View activityRootView, boolean isSoftKeyboardOpened) {
        this.activityRootView     = activityRootView;
        this.isSoftKeyboardOpened = isSoftKeyboardOpened;
        activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(this);
    }

    @Override
    public void onGlobalLayout() {
        final Rect r = new Rect();
        //r will be populated with the coordinates of your view that area still visible.
        activityRootView.getWindowVisibleDisplayFrame(r);

        final int heightDiff = activityRootView.getRootView().getHeight() - (r.bottom - r.top);
        if (!isSoftKeyboardOpened && heightDiff > 100) { // if more than 100 pixels, its probably a keyboard...
            isSoftKeyboardOpened = true;
            notifyOnSoftKeyboardOpened(heightDiff);
        } else if (isSoftKeyboardOpened && heightDiff < 100) {
            isSoftKeyboardOpened = false;
            notifyOnSoftKeyboardClosed();
        }
    }
    public void addSoftKeyboardStateListener(SoftKeyboardStateListener listener) {
        listeners.add(listener);
    }
    private void notifyOnSoftKeyboardOpened(int keyboardHeightInPx) {
        this.lastSoftKeyboardHeightInPx = keyboardHeightInPx;
        for (SoftKeyboardStateListener listener : listeners) {
            if (listener != null) {
                listener.onSoftKeyboardOpened(keyboardHeightInPx);
            }
        }
    }

    private void notifyOnSoftKeyboardClosed() {
        for (SoftKeyboardStateListener listener : listeners) {
            if (listener != null) {
                listener.onSoftKeyboardClosed();
            }
        }
    }
}

经过整合和解耦，使用起来很简单，直接调用一个方法即可，效果如下：