软键盘弹出时将ScrollView定位到指定布局位置的实现方案

方案一：自定义ScrollView监听软键盘，精准控制滚动位置 #

全屏Activity下，adjustPan和adjustResize的默认行为满足不了需求时，自定义ScrollView是最直接的解决方式：

1. 自定义ScrollView类，通过布局高度变化判断软键盘状态：

public class CustomScrollView extends ScrollView {
    private OnKeyboardVisibilityListener onKeyboardVisibilityListener;
    private int previousHeight;

    public CustomScrollView(Context context) {
        super(context);
    }

    public CustomScrollView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        if (previousHeight != 0) {
            boolean isKeyboardVisible = h < previousHeight;
            if (onKeyboardVisibilityListener != null) {
                onKeyboardVisibilityListener.onKeyboardVisibilityChanged(isVisible, previousHeight - h);
            }
        }
        previousHeight = h;
    }

    public interface OnKeyboardVisibilityListener {
        void onKeyboardVisibilityChanged(boolean isVisible, int keyboardHeight);
    }

    public void setOnKeyboardVisibilityListener(OnKeyboardVisibilityListener listener) {
        this.onKeyboardVisibilityListener = listener;
    }
}

2. 在Activity中设置监听，计算滚动偏移量实现需求：

CustomScrollView scrollView = findViewById(R.id.your_scroll_view);
LinearLayout targetLayout = findViewById(R.id.theLinearLayoutIWantToSee);
Button targetButton = findViewById(R.id.your_target_button);

scrollView.setOnKeyboardVisibilityListener((isVisible, keyboardHeight) -> {
    if (isVisible) {
        // 计算屏幕可用高度（减去软键盘高度）
        int screenAvailableHeight = getResources().getDisplayMetrics().heightPixels - keyboardHeight;
        // 获取目标Button在屏幕中的绝对位置
        int[] buttonLocation = new int[2];
        targetButton.getLocationOnScreen(buttonLocation);
        int buttonBottom = buttonLocation[1] + targetButton.getHeight();
        
        // 先让Button底部对齐屏幕可用区域底部
        int scrollDistance = buttonBottom - screenAvailableHeight;
        ScrollView scrollView = findViewById(R.id.your_scroll_view);
        if (scrollDistance > 0) {
            scrollView.smoothScrollBy(0, scrollDistance);
        } else {
            // 如果Button已在屏幕内，计算让目标布局居中的偏移量
            int[] targetLocation = new int[2];
            targetLayout.getLocationOnScreen(targetLocation);
            int targetTop = targetLocation[1];
            int targetHeight = targetLayout.getHeight();
            int desiredTop = (screenAvailableHeight - targetHeight) / 2;
            scrollDistance = targetTop - desiredTop;
            scrollView.smoothScrollBy(0, scrollDistance);
        }
    } else {
        // 软键盘收起后滚动回初始位置
        scrollView.smoothScrollTo(0, 0);
    }
});

3. Manifest中保持windowSoftInputMode="adjustResize"，确保ScrollView能感知布局高度变化。

方案二：用ViewTreeObserver直接监听布局变化（无需自定义ScrollView） #

如果不想自定义View，也可以在Activity中直接监听全局布局变化：

View rootView = findViewById(android.R.id.content);
rootView.getViewTreeObserver().addOnGlobalLayoutListener(() -> {
    Rect r = new Rect();
    rootView.getWindowVisibleDisplayFrame(r);
    int screenHeight = rootView.getRootView().getHeight();
    int keyboardHeight = screenHeight - r.bottom;
    
    // 当高度差超过屏幕15%时，判定为软键盘弹出
    if (keyboardHeight > screenHeight * 0.15) {
        LinearLayout targetLayout = findViewById(R.id.theLinearLayoutIWantToSee);
        Button targetButton = findViewById(R.id.your_target_button);
        
        int screenAvailableHeight = r.bottom;
        int[] buttonLocation = new int[2];
        targetButton.getLocationOnScreen(buttonLocation);
        int buttonBottom = buttonLocation[1] + targetButton.getHeight();
        
        int scrollDistance = buttonBottom - screenAvailableHeight;
        ScrollView scrollView = findViewById(R.id.your_scroll_view);
        if (scrollDistance > 0) {
            scrollView.smoothScrollBy(0, scrollDistance);
        } else {
            int[] targetLocation = new int[2];
            targetLayout.getLocationOnScreen(targetLocation);
            int targetTop = targetLocation[1];
            int targetHeight = targetLayout.getHeight();
            int desiredTop = (screenAvailableHeight - targetHeight) / 2;
            scrollDistance = targetTop - desiredTop;
            scrollView.smoothScrollBy(0, scrollDistance);
        }
    }
});

注意事项 #

• 确保全屏Activity未设置fitsSystemWindows="true"，避免干扰布局位置计算。
• 如果CustomEditText有自定义焦点逻辑，需在onFocusChanged方法中手动触发布局检查，确保软键盘弹出时能执行滚动逻辑。

内容的提问来源于stack exchange，提问作者Kulbuto