Android软键盘监听

Android软键盘监听

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开发中我们可能需要对软键盘进行监听，比如登陆页面，当软键盘抬起的时候，会将输入密码和登录按钮给遮挡住，用户输入完账号后得先按下软键盘再点击密码进行输入，体验很差，如下：

而我们想要如下效果：

~这就需要针对软件盘做一些操作了~

参考资料：http://www.cnblogs.com/shelly-li/p/5639833.html and http://www.2cto.com/kf/201405/298962.html将这两篇博客结合在一起，完美解决问题

一、在AndroidManifest.xml文件中对当前activity添加 android:windowSoftInputMode=”adjustResize|stateHidden”

二、自定义监听软件盘的布局

public class KeyboardLayout extends RelativeLayout {

private onSizeChangedListener mChangedListener;
private static final String TAG = "KeyboardLayoutTAG";
private boolean mShowKeyboard = false;

public KeyboardLayout(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    // TODO Auto-generated constructor stub
}

public KeyboardLayout(Context context, AttributeSet attrs) {
    super(context, attrs);
    // TODO Auto-generated constructor stub
}

public KeyboardLayout(Context context) {
    super(context);
    // TODO Auto-generated constructor stub
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    // TODO Auto-generated method stub
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    Log.d(TAG, "onMeasure-----------");
}

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
    // TODO Auto-generated method stub
    super.onLayout(changed, l, t, r, b);
}

@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    // TODO Auto-generated method stub
    super.onSizeChanged(w, h, oldw, oldh);
    if (null != mChangedListener && 0 != oldw && 0 != oldh) {
        if (h < oldh) {
            mShowKeyboard = true;
        } else {
            mShowKeyboard = false;
        }
        mChangedListener.onChanged(mShowKeyboard);
    }
}

public void setOnSizeChangedListener(onSizeChangedListener listener) {
    mChangedListener = listener;
}

public interface onSizeChangedListener {

    void onChanged(boolean showKeyboard);
}
}

三、布局文件使用我们自定义的布局，将其放入根节点：

四、还需要写一个类，是对软键盘adjustResize属性的修复

public class AndroidAdjustResizeBugFix {
private View mChildOfContent;
private int usableHeightPrevious;
private int statusBarHeight;
private FrameLayout.LayoutParams frameLayoutParams;
private Activity mActivity;

private AndroidAdjustResizeBugFix(Activity activity) {
    mActivity = activity;
    FrameLayout content = (FrameLayout) activity.findViewById(android.R.id.content);
    mChildOfContent = content.getChildAt(0);
    statusBarHeight = getStatusBarHeight();
    mChildOfContent.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
        public void onGlobalLayout() {
            possiblyResizeChildOfContent();
        }
    });
    frameLayoutParams = (FrameLayout.LayoutParams) mChildOfContent.getLayoutParams();
}
public static void assistActivity(Activity activity) {
    new AndroidAdjustResizeBugFix(activity);
}
private void possiblyResizeChildOfContent() {
    int usableHeightNow = computeUsableHeight();
    if (usableHeightNow != usableHeightPrevious) {
        int usableHeightSansKeyboard = mChildOfContent.getRootView().getHeight();
        int heightDifference = usableHeightSansKeyboard - usableHeightNow;
        if (heightDifference > (usableHeightSansKeyboard / 4)) {
            // keyboard probably just became visible
            // 如果有高度变化，mChildOfContent.requestLayout()之后界面才会重新测量
            // 这里就随便让原来的高度减去了1
            frameLayoutParams.height = usableHeightSansKeyboard - 1;
        } else {
            // keyboard probably just became hidden
            frameLayoutParams.height = usableHeightSansKeyboard;
        }
        mChildOfContent.requestLayout();
        usableHeightPrevious = usableHeightNow;
    }
}
private int computeUsableHeight() {
    Rect r = new Rect();
    mChildOfContent.getWindowVisibleDisplayFrame(r);
    return r.bottom - r.top + statusBarHeight;
}
private int getStatusBarHeight() {
    try {
        Class<?> c = Class.forName("com.android.internal.R$dimen");
        Object obj = c.newInstance();
        Field field = c.getField("status_bar_height");
        int x = Integer.parseInt(field.get(obj).toString());
        int dimensionPixelSize = mActivity.getResources().getDimensionPixelSize(x);
        return dimensionPixelSize;
    } catch (Exception e) {
        e.printStackTrace();
    }
    return 0;
}
}

五、在当前activity的oncreate方法中加入 AndroidAdjustResizeBugFix.assistActivity(this);

给我们自定义的布局添加软键盘监听

 mRootView.setOnSizeChangedListener(new KeyboardLayout.onSizeChangedListener() {
        @Override
        public void onChanged(boolean showKeyboard) {
            if (showKeyboard) {
                mHandler.sendMessage(mHandler.obtainMessage(KEYBOARD_SHOW));
            } else {
                mHandler.sendMessage(mHandler.obtainMessage(KEYBOARD_HIDE));
            }
        }
    });

然后在Handler中进行后续操作

 private Handler mHandler = new Handler() {

    @Override
    public void handleMessage(Message msg) {
        super.handleMessage(msg);
        switch (msg.what) {
            case KEYBOARD_HIDE:
                mContentView.setPadding(0, 0, 0, 0);
                break;

            case KEYBOARD_SHOW:
              //mContentView.setPadding(0,"需要移动的距离",0,0);
                break;

            default:
                break;
        }
    }

};