android 软键盘的弹出问题总结

项目中用到软键盘的管理总结如下：

在开始进入页面时不弹出键盘

方法一：在包含EditText外层布局上添加

android:focusable="true"
android:focusableInTouchMode="true"

抢在EditText获取焦点，即可

原理 view touch source：

public boolean onTouchEvent(MotionEvent event) {
    ...
    if (((viewFlags & CLICKABLE) == CLICKABLE || 
        (viewFlags & LONG_CLICKABLE) == LONG_CLICKABLE)) {
        ...
        if (isFocusable() && isFocusableInTouchMode()
            && !isFocused()) {
                focusTaken = requestFocus();
        }
        ...
    }
    ...
}

即一个子view想要获取焦点必须满足clickable, focusable, focusableInTouchMode 属性为true，缺一不可.

方法二：在onResume中加入这行代码

getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE |
                WindowManager.LayoutParams.SOFT_INPUT_STATE_HIDDEN);

软键盘出现把原来的布局底部拦布局给顶上去的方法解决办法:

android:windowSoftInputMode="adjustPan|stateHidden"

将按钮恰好显示在键盘之上？
<activity   
    android:windowSoftInputMode="adjustResize"
当键盘弹起时，Activity就会重新布局，以键盘的上方作为整个页面布局的底部。我们只需要将“NEXT”按钮的属性设置为：
    android:layout_alignParentBottom="true"      
    不是一个页面的，一个activity，多个页面的，每个页面只是一个Fragment
    在按钮的布局之上，添加了一个高度为0dp的ScrollView才解决
   

<ScrollView
                android:layout_width="match_parent"
                android:layout_height="0dp"
                />
            <Button
                android:id="@+id/entry_btn"
                android:layout_width="match_parent"
                android:layout_height="45dp"
                android:layout_alignParentBottom="true"

1,绑定软键盘到EditText：

      edit.setFocusable(true);
	edit.setFocusableInTouchMode(true);
	edit.requestFocus();
	InputMethodManager inputManager = (InputMethodManager)edit.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
	 inputManager.showSoftInput(edit, 0);    

2，点击空白区域去除EditText软键盘显示：

重写Activity dispatchTouch

@Override
public boolean dispatchTouchEvent(MotionEvent event) {
    if (event.getAction() == MotionEvent.ACTION_DOWN) {
        View v = getCurrentFocus();
        if ( v instanceof EditText) {
            Rect outRect = new Rect();
            v.getGlobalVisibleRect(outRect);
            if (!outRect.contains((int)event.getRawX(), (int)event.getRawY())) {
                v.clearFocus();
                InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
                imm.hideSoftInputFromWindow(v.getWindowToken(), 0);
            }
        }
    }
    return super.dispatchTouchEvent( event );
}

EditText始终不弹出软件键盘

EditText edit=(EditText)findViewById(R.id.edit); edit.setInputType(InputType.TYPE_NULL);

还可以

InputMethodManager imm = (InputMethodManager)v.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);   

　　if(imm.isActive()){   //这里可以判断也可以不判断

　　　　imm.hideSoftInputFromWindow(v.getApplicationWindowToken(), 0 );   

　　}   

1，在设置软键盘弹出属性界面加载后,软键盘不能弹出，不能弹出软键盘的主要原因是Android程序未将屏幕绘制完成,所以延迟一定时间，弹出软键盘。

方法一：

private Handler hander=new Handler(){
		public void handleMessage(android.os.Message msg) {
			edit.setFocusable(true);
			edit.setFocusableInTouchMode(true);
			edit.requestFocus();
			InputMethodManager inputManager = (InputMethodManager)edit.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
	        inputManager.showSoftInput(edit, 0);
		};
	};

@Override
		public void onWindowFocusChanged(boolean hasWindowFocus) {
			if(visible){	
				hander.sendEmptyMessageDelayed(0, 1000);
			}
		}

方法二：

Timer timer = new Timer();
timer.schedule(new TimerTask() {
	@Override
	public void run() {
		InputMethodManager m = (InputMethodManager) editText.getContext().getSystemService(Context.INPUT_METHOD_SERVICE);
		m.toggleSoftInput(0, InputMethodManager.HIDE_NOT_ALWAYS);
	}
}, 300);

 
<activity android:windowSoftInputMode="stateVisible|adjustResize" . . . >
 该Activity主窗口总是被调整屏幕的大小以便留出软键盘的空间

软键盘打开，关闭监控：来源girhub:

import android.app.Activity;
import android.os.Build;
import android.view.View;
import android.view.ViewTreeObserver;
import android.view.Window;
import android.view.WindowManager;

import java.lang.ref.WeakReference;

/**
 * Created by froger_mcs on 21/03/16.
 */
public class KeyboardWatcher {

    private WeakReference<Activity> activityRef;
    private WeakReference<View> rootViewRef;
    private WeakReference<OnKeyboardToggleListener> onKeyboardToggleListenerRef;
    private ViewTreeObserver.OnGlobalLayoutListener viewTreeObserverListener;

    public KeyboardWatcher(Activity activity) {
        activityRef = new WeakReference<>(activity);
        initialize();
    }

    public void setListener(OnKeyboardToggleListener onKeyboardToggleListener) {
        onKeyboardToggleListenerRef = new WeakReference<>(onKeyboardToggleListener);
    }

    public void destroy() {
        if (rootViewRef.get() != null)
            if (Build.VERSION.SDK_INT >= 16) {
                rootViewRef.get().getViewTreeObserver().removeOnGlobalLayoutListener(viewTreeObserverListener);
            } else {
                rootViewRef.get().getViewTreeObserver().removeGlobalOnLayoutListener(viewTreeObserverListener);
            }
    }

    private void initialize() {
        if (hasAdjustResizeInputMode()) {
            viewTreeObserverListener = new GlobalLayoutListener();
            rootViewRef = new WeakReference<>(activityRef.get().findViewById(Window.ID_ANDROID_CONTENT));
            rootViewRef.get().getViewTreeObserver().addOnGlobalLayoutListener(viewTreeObserverListener);
        } else {
            throw new IllegalArgumentException(String.format("Activity %s should have windowSoftInputMode=\"adjustResize\"" +
                    "to make KeyboardWatcher working. You can set it in AndroidManifest.xml", activityRef.get().getClass().getSimpleName()));
        }
    }

    private boolean hasAdjustResizeInputMode() {
        return (activityRef.get().getWindow().getAttributes().softInputMode & WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE) != 0;
    }

    private class GlobalLayoutListener implements ViewTreeObserver.OnGlobalLayoutListener {
        int initialValue;
        boolean hasSentInitialAction;
        boolean isKeyboardShown;

        @Override
        public void onGlobalLayout() {
            if (initialValue == 0) {
                initialValue = rootViewRef.get().getHeight();
            } else {
                if (initialValue > rootViewRef.get().getHeight()) {
                    if (onKeyboardToggleListenerRef.get() != null) {
                        if (!hasSentInitialAction || !isKeyboardShown) {
                            isKeyboardShown = true;
                            onKeyboardToggleListenerRef.get().onKeyboardShown(initialValue - rootViewRef.get().getHeight());
                        }
                    }
                } else {
                    if (!hasSentInitialAction || isKeyboardShown) {
                        isKeyboardShown = false;
                        rootViewRef.get().post(new Runnable() {
                            @Override
                            public void run() {
                                if (onKeyboardToggleListenerRef.get() != null) {
                                    onKeyboardToggleListenerRef.get().onKeyboardClosed();
                                }
                            }
                        });
                    }
                }
                hasSentInitialAction = true;
            }
        }
    }

    public interface OnKeyboardToggleListener {
        void onKeyboardShown(int keyboardSize);

        void onKeyboardClosed();
    }
}

使用监控：

<activity
    android:name=".MainActivity"
    android:windowSoftInputMode="adjustResize" />
    
   keyboardWatcher = new KeyboardWatcher(this);
  keyboardWatcher.setListener(this);

Kotlin扩展解决View focus弹出键盘时机

fun View.focusAndShowKeyboard() {
   /**
    * This is to be called when the window already has focus.
    */
   fun View.showTheKeyboardNow() {
       if (isFocused) {
           post {
               // We still post the call, just in case we are being notified of the windows focus
               // but InputMethodManager didn't get properly setup yet.
               val imm = context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
               imm.showSoftInput(this, InputMethodManager.SHOW_IMPLICIT)
           }
       }
   }

   requestFocus()
   if (hasWindowFocus()) {
       // No need to wait for the window to get focus.
       showTheKeyboardNow()
   } else {
       // We need to wait until the window gets focus.
       viewTreeObserver.addOnWindowFocusChangeListener(
           object : ViewTreeObserver.OnWindowFocusChangeListener {
               override fun onWindowFocusChanged(hasFocus: Boolean) {
                   // This notification will arrive just before the InputMethodManager gets set up.
                   if (hasFocus) {
                       this@focusAndShowKeyboard.showTheKeyboardNow()
                       // It’s very important to remove this listener once we are done.
                       viewTreeObserver.removeOnWindowFocusChangeListener(this)
                   }
               }
           })
   }
}

自定义EditText

class FixedKeyboardEditText(context: Context, attributeSet: AttributeSet?) : EditText(context, attributeSet) {
 private var showKeyboardDelayed = false
 /**
  * Will request focus and try to show the keyboard.
  * It has into account if the containing window has focus or not yet.
  * And delays the call to show keyboard until it's gained.
  */
 fun focusAndShowKeyboard() {
   requestFocus()
   showKeyboardDelayed = true
   maybeShowKeyboard()
 }

 @Override
 override fun onWindowFocusChanged(hasWindowFocus: Boolean) {
   super.onWindowFocusChanged(hasWindowFocus);
   maybeShowKeyboard()
 }

 private fun maybeShowKeyboard() {
   if (hasWindowFocus() && showKeyboardDelayed) {
     if (isFocused) {
       post {
         val imm = context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
         imm.showSoftInput(this@FixedKeyboardEdit, InputMethodManager.SHOW_IMPLICIT)
       }
     }
     showKeyboardDelayed = false
   }
 }
}

参考：https://developer.squareup.com/blog/showing-the-android-keyboard-reliably