Button自边距

部分主题下（如AppCompatActivity），Button会自带边距，并且padding、margin设为0也没用；

android:minWidth="0dp"

PopupWindow关闭

点击外部取消和点击返回键取消

final PopupWindow popWindow = new PopupWindow(
        view,
        LinearLayout.LayoutParams.MATCH_PARENT,
        LinearLayout.LayoutParams.WRAP_CONTENT, 
        true  //  点击外部取消，还不行添加下面注释代码
);
//      popWindow.setTouchable(true);
//      popWindow.setOutsideTouchable(true);
//      popWindow.setBackgroundDrawable(new ColorDrawable());
//  点击返回键取消
view.setOnKeyListener(new View.OnKeyListener(){
    @Override
    public boolean onKey(View arg0, int arg1, KeyEvent arg2) {
        if (arg1 == KeyEvent.KEYCODE_BACK){
            popWindow.dismiss();
        }
        return false;
    }
});

ImageView图片适配

        LinearLayout.LayoutParams linearParams =(LinearLayout.LayoutParams) ivLogo.getLayoutParams();
        Drawable drawable = ContextCompat.getDrawable(this, R.drawable.bg_about);
        linearParams.width = DisplayUtil.getScreenWidth(this);
        linearParams.height = (int) (DisplayUtil.getScreenWidth(this) / (float) drawable.getIntrinsicWidth() * drawable.getIntrinsicHeight());
        ivLogo.setLayoutParams(linearParams);

点击编辑框外部取消软键盘

    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        View view = getCurrentFocus();
        if (view != null && ev.getAction() == MotionEvent.ACTION_DOWN && view instanceof EditText) {
            int[] location = new int[2];
            view.getLocationOnScreen(location);
            int x = location[0], y = location[1];
            if(ev.getX() < x || ev.getX() > (x + view.getWidth()) || ev.getY() < y || ev.getY() > (y + view.getHeight())){
                InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
                if (imm != null) {
                    imm.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), 0);
                }
            }
        }
        return super.dispatchTouchEvent(ev);
    }