在没有xml

Question

我想在不使用xml的情况下设置RecyclerView行的边距，因为有时我有两行，我需要动态更改边距。但是当我启动程序时，没有设置保证金。是否有人能够回答我做错了什么？

我的xml文件供了解：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_height="match_parent"
    android:layout_width="match_parent"
    android:focusable="true"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:clickable="true"
    android:background="?android:attr/selectableItemBackground"
    android:orientation="vertical">

    <TextView
        android:id="@+id/settingTitle"
        android:textColor="@color/colorBlack"
        android:layout_width="match_parent"
        android:textSize="16dp"
        android:layout_height="wrap_content" />

    <TextView
        android:id="@+id/settingSubtitle"
        android:layout_below="@id/settingTitle"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

</RelativeLayout>

这是我的适配器上的onBind：

@Override
    public void onBindViewHolder(MySettingHolder holder, int position) {
        // Setting for one entry
        Settings setting = settingList.get(position);
        RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.WRAP_CONTENT);


        // If the settingSubtitle is empty it should be not visible and just the settingTitle
        if (setting.getSettingSubtitle().equals("")) {
            params.setMargins(0, 18, 0, 18);
            holder.settingTitle.setLayoutParams(params);
            holder.settingTitle.setText(setting.getSettingTitle());
            holder.settingSubtitle.setVisibility(View.GONE);
        } else {
            // Set Margins for settingTitle
            params.setMargins(0, 18, 0, 18);
            holder.settingTitle.setLayoutParams(params);
            // Set Margins for settingSubtitle
            params.setMargins(0, 0, 0, 18);
            holder.settingSubtitle.setLayoutParams(params);
            holder.settingTitle.setText(setting.getSettingTitle());
            holder.settingSubtitle.setText(setting.getSettingSubtitle());
        }
    }

Answer 1

如果我正确理解您的问题，您希望它影响整个RecyclerView而不是每行？以下是解决方案。

当您在进入适配器之前初始化RecyclerView Activity/Fragment时，如果您想影响整个RecyclerView，onBindViewHolder，则应设置边距。绑定您为每行提供的布局并逐行操作那些小部件，因此边距将影响每一行而不是RecyclerView。

Activity / Fragment中的代码示例如下：

 recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
 recyclerView.setHasFixedSize(true);
 RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getActivity(), LinearLayoutManager.VERTICAL, false);
 RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
 params.setMargins(0, 18, 0, 18);
 recyclerView.setLayoutParams(params);

Answer 2

<强>解

我已经尝试了很多天来解决我的问题。其他答案并不是很有帮助。我的问题是我如何在没有XML的情况下将余量设置到RecyclerView行中的TextView（因为有时我只有一个TextView而不是两个）：

这是在我的情况下如何在Android中的适配器中定义新的边距：

// Create new LayoutParams object
        RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.WRAP_CONTENT);

// Define values in dp and calculate pixels from it because margins are with pixels
int dpValueBottom = 14;
int dpValueLeft = 40;
float d = customContext.getResources().getDisplayMetrics().density;
int marginStandard = (int)(dpValueBottom * d);
int marginLeft = (int)(dpValueLeft * d);

holder.settingImage.setImageResource(setting.getSettingImageUrl());
// If the settingSubtitle is empty it should be not visible and just the settingTitle
if (setting.getSettingSubtitle().equals("")) {
    holder.settingTitle.setText(setting.getSettingTitle());
    holder.settingSubtitle.setVisibility(View.GONE);

    // Get settingTitle TextView
    TextView settingTitle = holder.settingTitle;

    // Set margin to params
    params.setMargins(marginLeft, marginStandard, 0, marginStandard);

    // Set params to settingTitle
    settingTitle.setLayoutParams(params);

} else {
    holder.settingTitle.setText(setting.getSettingTitle());
    holder.settingSubtitle.setText(setting.getSettingSubtitle());
}

我希望我可以帮助这个答案。