在 ListView 中一次显示单个项目
Show single item at a time in ListView
我正在开发 WearOS 应用程序。我正在使用 ListView 来显示字符串列表。现在,ListView 看起来像这样:
我想要一行占据整个屏幕。一旦用户向上滑动,第 2 行就会占据整个屏幕。再次向上滑动,第 3 行占据整个屏幕,等等。所以像这样:
我遇到了这个,这正是我想要做的,但是第一种方法不起作用,第二种方法建议使用库,但我不想使用库这似乎是一项非常简单的任务。我不想使用 RecyclerView。谢谢您的帮助。
这是我的 XML 主 activity 文件,这是 ListView 所在的位置。
<?xml version="1.0" encoding="utf-8"?>
<android.support.wear.widget.BoxInsetLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/dark_grey"
android:padding="@dimen/box_inset_layout_padding"
tools:context=".MainActivity"
tools:deviceIds="wear">
<!-- Change FrameLayout to a RelativeLayour -->
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="@dimen/inner_frame_layout_padding"
app:boxedEdges="all">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true" />
</RelativeLayout>
</android.support.wear.widget.BoxInsetLayout>
尝试以下操作(这里的想法是以编程方式将 textView 的高度设置为屏幕的高度):
1) MnnnnnnnActivity.class:------------
public class MnnnnnnnActivity extends AppCompatActivity {
private ListView lv;
private CustomAdapter customAdapter;
private String[] s = new String[10];
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout6);
for (int i = 0; i < 10; i++) {
s[i] = "ROW " + String.valueOf(i + 1);
}
lv = (ListView) findViewById(R.id.lv);
customAdapter = new CustomAdapter(MnnnnnnnActivity.this, s);
lv.setAdapter(customAdapter);
}
public int getScreenHeight() {
DisplayMetrics displayMetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
return displayMetrics.heightPixels;
}
}
2) CustomAdapter.class:--------
public class CustomAdapter extends ArrayAdapter<String> {
private String[] s;
private WeakReference<MnnnnnnnActivity> mActivity;
public CustomAdapter(MnnnnnnnActivity activity1, String[] s) {
super(activity1.getApplicationContext(), R.layout.list_view_item, s);
this.s = s;
mActivity = new WeakReference<MnnnnnnnActivity>(activity1);
}
@NonNull
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if(mActivity != null) {
MnnnnnnnActivity activity = mActivity.get();
if (activity != null) {
if (convertView == null) {
LayoutInflater inflater = LayoutInflater.from(activity);
convertView = inflater.inflate(R.layout.list_view_item, null);
holder = new ViewHolder();
holder.tv = (TextView) convertView.findViewById(R.id.tv);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.tv.setText(s[position]);
holder.tv.setHeight(activity.getScreenHeight());
}
}
return convertView;
}
private class ViewHolder {
TextView tv;
}
}
3) layout6.xml:------------
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/lv">
</ListView>
</android.support.constraint.ConstraintLayout>
4) list_view_item.xml:------------
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/tv"
android:singleLine="true"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="-"
android:gravity="center"
android:textSize="20sp"
android:textStyle="bold">
</TextView>
</LinearLayout>
5) 注意:虽然这是在 phone 上测试的,但同样的想法可以用于在 wareable 上实现类似的东西。此外,更好的方法是将 linearLayout(包含 textView)的高度设置为屏幕高度。
6) 输出:
我正在开发 WearOS 应用程序。我正在使用 ListView 来显示字符串列表。现在,ListView 看起来像这样:
我想要一行占据整个屏幕。一旦用户向上滑动,第 2 行就会占据整个屏幕。再次向上滑动,第 3 行占据整个屏幕,等等。所以像这样:
我遇到了这个
这是我的 XML 主 activity 文件,这是 ListView 所在的位置。
<?xml version="1.0" encoding="utf-8"?>
<android.support.wear.widget.BoxInsetLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/dark_grey"
android:padding="@dimen/box_inset_layout_padding"
tools:context=".MainActivity"
tools:deviceIds="wear">
<!-- Change FrameLayout to a RelativeLayour -->
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="@dimen/inner_frame_layout_padding"
app:boxedEdges="all">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true" />
</RelativeLayout>
</android.support.wear.widget.BoxInsetLayout>
尝试以下操作(这里的想法是以编程方式将 textView 的高度设置为屏幕的高度):
1) MnnnnnnnActivity.class:------------
public class MnnnnnnnActivity extends AppCompatActivity {
private ListView lv;
private CustomAdapter customAdapter;
private String[] s = new String[10];
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.layout6);
for (int i = 0; i < 10; i++) {
s[i] = "ROW " + String.valueOf(i + 1);
}
lv = (ListView) findViewById(R.id.lv);
customAdapter = new CustomAdapter(MnnnnnnnActivity.this, s);
lv.setAdapter(customAdapter);
}
public int getScreenHeight() {
DisplayMetrics displayMetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
return displayMetrics.heightPixels;
}
}
2) CustomAdapter.class:--------
public class CustomAdapter extends ArrayAdapter<String> {
private String[] s;
private WeakReference<MnnnnnnnActivity> mActivity;
public CustomAdapter(MnnnnnnnActivity activity1, String[] s) {
super(activity1.getApplicationContext(), R.layout.list_view_item, s);
this.s = s;
mActivity = new WeakReference<MnnnnnnnActivity>(activity1);
}
@NonNull
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if(mActivity != null) {
MnnnnnnnActivity activity = mActivity.get();
if (activity != null) {
if (convertView == null) {
LayoutInflater inflater = LayoutInflater.from(activity);
convertView = inflater.inflate(R.layout.list_view_item, null);
holder = new ViewHolder();
holder.tv = (TextView) convertView.findViewById(R.id.tv);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.tv.setText(s[position]);
holder.tv.setHeight(activity.getScreenHeight());
}
}
return convertView;
}
private class ViewHolder {
TextView tv;
}
}
3) layout6.xml:------------
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/lv">
</ListView>
</android.support.constraint.ConstraintLayout>
4) list_view_item.xml:------------
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/tv"
android:singleLine="true"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="-"
android:gravity="center"
android:textSize="20sp"
android:textStyle="bold">
</TextView>
</LinearLayout>
5) 注意:虽然这是在 phone 上测试的,但同样的想法可以用于在 wareable 上实现类似的东西。此外,更好的方法是将 linearLayout(包含 textView)的高度设置为屏幕高度。
6) 输出: