android 监听键盘是否弹起，并根据键盘的弹起控制键盘显示关闭

直接撸码：

package com.example.administrator.keyboardapplication;

import android.content.Context;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnLayoutChangeListener {

    private View activityRootView;

    private int screenHeight = 0;
    private int keyHeight = 0;

    private Button myButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        activityRootView = findViewById(R.id.root_layout);
        screenHeight = this.getWindowManager().getDefaultDisplay().getHeight();

        myButton = findViewById(R.id.button);
        myButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
                imm.hideSoftInputFromWindow(myButton.getWindowToken(),0);
            }
        });
        keyHeight = screenHeight/3;
        activityRootView.addOnLayoutChangeListener(this);

    }


    @Override
    public void onLayoutChange(View v, int left, int top, int right, int bottom,
                               int oldLeft, int oldTop, int oldRight, int oldBottom) {
        Log.i("iven","left:"+left+"\nright:"+right+"\ntop:"+top+"\nbottom:"+bottom);
        Log.i("iven","oldleft:"+oldLeft+"\nOldright:"+oldRight+"\ntop:"+oldTop+"\nbottom:"+oldBottom);

        //现在认为只要控件将Activity向上推的高度超过了1/3屏幕高，就认为软键盘弹起
        if(oldBottom != 0 && bottom != 0 &&(oldBottom - bottom > keyHeight)){

            Toast.makeText(MainActivity.this, "监听到软键盘弹起...", Toast.LENGTH_SHORT).show();

        }else if(oldBottom != 0 && bottom != 0 &&(bottom - oldBottom > keyHeight)){

            Toast.makeText(MainActivity.this, "监听到软件盘关闭...", Toast.LENGTH_SHORT).show();

        }

    }
}