聊聊软键盘的那些事

①onDestroy进行调用防止内存泄漏

    /**
     * 解决InputMethodManager内存泄露现象
     */
    private static void fixInputMethodManagerLeak(Context destContext) {

        if (destContext == null)
            return;

        InputMethodManager imm = (InputMethodManager) destContext.getSystemService(Context.INPUT_METHOD_SERVICE);

        if (imm == null)
            return;

        String[] arr = new String[]{"mCurRootView", "mServedView", "mNextServedView"};
        Field f;
        Object obj_get;
        for (String param : arr) {
            try {
                f = imm.getClass().getDeclaredField(param);
                if (!f.isAccessible()) {
                    f.setAccessible(true);
                } // author: sodino mail:sodino@qq.com
                obj_get = f.get(imm);
                if (obj_get != null && obj_get instanceof View) {
                    View v_get = (View) obj_get;
                    if (v_get
                            .getContext() == destContext) { // 被InputMethodManager持有引用的context是想要目标销毁的
                        f.set(imm, null); // 置空，破坏掉path to gc节点
                    } else {
                        // 不是想要目标销毁的，即为又进了另一层界面了，不要处理，避免影响原逻辑,也就不用继续for循环了
                        /*if (QLog.isColorLevel()) {
                            QLog.d(ReflecterHelper.class.getSimpleName(), QLog.CLR, "fixInputMethodManagerLeak break, context is not suitable, get_context=" + v_get.getContext()+" dest_context=" + destContext);
                        }*/
                        break;
                    }
                }
            } catch (Throwable t) {
                t.printStackTrace();
            }
        }
    }

②键盘遮挡EditText

假如EditText 基本贴近屏幕底部，弹出软键盘是会遮挡住EditText所填写的内容 ，如果清单文件设置windowSoftInputMode：adjustPan 则会把toolbar顶出屏幕

<1>用ScrollView进行包裹Edittext

<LinearLayout ... >
    <Toolar ... />
    <ScrollView ... >
        <Edittext ... />
        ... 
    </ScrollView>
</LinearLayout>

<2>在根布局的layout下设置android:fitsSystemWindows="true"
<3>如果设置了状态栏透明，需要自定义了一个根布局并设置android:fitsSystemWindows="true"

// extends LinearLayout、RelativeLayout等写法一样
public class SoftInputLinearLayout extends LinearLayout {

    private int[] mInsets = new int[4];

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

    public SoftInputLinearLayout(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
    }


    @Override
    public WindowInsets computeSystemWindowInsets(WindowInsets in, Rect outLocalInsets) {

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            // Intentionally do not modify the bottom inset. For some reason,
            // if the bottom inset is modified, window resizing stops working.
            // TODO: Figure out why.

            mInsets[0] = outLocalInsets.left;
            mInsets[1] = outLocalInsets.top;
            mInsets[2] = outLocalInsets.right;

            outLocalInsets.left = 0;
            outLocalInsets.top = 0;
            outLocalInsets.right = 0;
        }

        return super.computeSystemWindowInsets(in, outLocalInsets);

    }

    @Override
    public WindowInsets onApplyWindowInsets(WindowInsets insets) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT_WATCH) {
            mInsets[0] = insets.getSystemWindowInsetLeft();
            mInsets[1] = insets.getSystemWindowInsetTop();
            mInsets[2] = insets.getSystemWindowInsetRight();
            return super.onApplyWindowInsets(insets.replaceSystemWindowInsets(0, 0, 0,
                    insets.getSystemWindowInsetBottom()));
        } else {
            return insets;
        }
    }
}