Android中检测软键盘的弹出和关闭

Android系统并没有提供明显的API来监听软键盘的弹出和关闭,但是在某些情况下我们还是有办法来检测软键盘的弹出和关闭。
从StackOverflow找到了一个不错的方法。但是这种只适用于在manifest中目标Activity设置android:windowSoftInputMode=”adjustResize”的情况。
adjustResize表示The activity’s main window is always resized to make room for the soft keyboard on screen.
然后我们需要设置Activity的根视图的id,用来判断对话框弹出关闭使用。

布局的示例代码:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" 
    android:id="@+id/root_layout"
    >
 
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:padding="@dimen/padding_medium"
        android:text="@string/hello_world"
        tools:context=".MainActivity" />
 
    <EditText 
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
 
        />
 
</RelativeLayout>


判断对话框出现或者关闭的逻辑代码如下:

@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final View activityRootView = findViewById(R.id.root_layout);
        activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
			private int preHeight = 0;
			@Override
			public void onGlobalLayout() {
		        int heightDiff = activityRootView.getRootView().getHeight() - activityRootView.getHeight();
		        System.out.println("height differ = " + heightDiff);
		        //在数据相同时,减少发送重复消息。因为实际上在输入法出现时会多次调用这个onGlobalLayout方法。
		        if (preHeight == heightDiff) {
					return;
		        }
		        preHeight = heightDiff;
		        if (heightDiff > 100 ) {
//		        	System.out.println("input method shown!");
		        	Toast.makeText(getApplicationContext(), "keyboard is  shown", Toast.LENGTH_SHORT).show();
		        } else {
		        	Toast.makeText(getApplicationContext(), "keyboard is hidden ", Toast.LENGTH_SHORT).show();
		        }
			}
 
        });
    }


give your activity’s root view a known ID, say ‘@+id/activityRoot’, hook a GlobalLayoutListener into the ViewTreeObserver,
and from there calculate the size diff between your activity’s view root and the window size

给你的Activity的根视图设置一个id,比如说”@+id/activityRoot”,在ViewTreeObserver上设置一个GlobalLayoutListener。然后计算你的Activity的根视图和Window尺寸的差值
如果插值大于 100 (这是一个相对比较合理的值),就认为是对话框弹出,否则为对话框隐藏。

相关链接:http://stackoverflow.com/questions/2150078/how-to-check-visibility-of-software-keyboard-in-android



原文地址:https://www.cnblogs.com/jiangu66/p/3170245.html