5 回答
好的多选你需要模型,适配器。所以你必须制作customlistview。我在下面给出了一个例子。你只需将markAttendance_detail(TextView)替换为复选框,如果它如果'P'设置复选框,则选中其他未选中。并且如果您遇到任何问题,请告诉我。
适配器类-->
public class AttendanceAdapter extends ArrayAdapter {
List list = new ArrayList();
static class DataHolder {
TextView rollNo_detail,studentName_detail,markAttendance_detail;
}
public AttendanceAdapter(Context context, int resource) {
super(context, resource);
}
@Override
public void add(Object object) {
super.add(object);
list.add(object);
}
@Override
public int getCount() {
return this.list.size();
}
@Override
public Object getItem(int position) {
return this.list.get(position);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row;
row = convertView;
final DataHolder dataHolder;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) this.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
row = inflater.inflate(R.layout.attendance_list, parent, false);
dataHolder = new DataHolder();
dataHolder.rollNo_detail=(TextView)row.findViewById(R.id.student_rollno);
dataHolder.studentName_detail=(TextView)row.findViewById(R.id.student_name);
dataHolder.markAttendance_detail=(TextView)row.findViewById(R.id.mark_attendance);
dataHolder.markAttendance_detail.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
AttendanceModel model=(AttendanceModel) dataHolder.markAttendance_detail.getTag();
String att=model.getAttendance().toString();
if (model.isSelected()==false){
model.setSelected(true);
dataHolder.markAttendance_detail.setText("P");
}else if (model.isSelected()==true){
model.setSelected(false);
dataHolder.markAttendance_detail.setText("A");
}
}
});
row.setTag(dataHolder);
dataHolder.markAttendance_detail.setTag(list.get(position));
}
else {
dataHolder = (DataHolder) row.getTag();
((DataHolder) row.getTag()).markAttendance_detail.setTag(list.get(position));
}
AttendanceModel model = (AttendanceModel) this.getItem(position);
dataHolder.rollNo_detail.setText(model.getRoll_no());
dataHolder.studentName_detail.setText(model.getStudent_name());
if (model.isSelected()==true){
dataHolder.markAttendance_detail.setText("P");
}else if (model.isSelected()==false){
dataHolder.markAttendance_detail.setText("A");
}
return row;
}
模型应该是这样的-->
public class AttendanceModel {
private String roll_no;
private String student_name;
private String attendance;
private boolean selected;
public AttendanceModel(String roll_no,String student_name,String attendance){
this.roll_no=roll_no;
this.selected=true;
this.student_name=student_name;
this.attendance=attendance;
}
public boolean isSelected() {
return selected;
}
public void setSelected(boolean selected) {
this.selected = selected;
}
public String getRoll_no() {
return roll_no;
}
public void setRoll_no(String roll_no) {
this.roll_no = roll_no;
}
public String getStudent_name() {
return student_name;
}
public void setStudent_name(String student_name) {
this.student_name = student_name;
}
public String getAttendance() {
return attendance;
}
public void setAttendance(String attendance) {
this.attendance = attendance;
}
}
而Activity应该是这样的-->
public class Attendance_Page extends AppCompatActivity {
ListView listView;
AttendanceModel model;
AttendanceAdapter attendanceAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_atendance_page);
listView= (ListView) findViewById(R.id.attendancepage_list_view);
attendanceAdapter=new AttendanceAdapter(getApplicationContext(),R.layout.attendance_list);
listView.setAdapter(attendanceAdapter);
for (int i=1;i<=10;i++){
model=new AttendanceModel("1","Aryan","P");
attendanceAdapter.add(model);
}
}
}
从我的角度来看,如果不让我知道,这可能是解决方案。
“我最感兴趣的是根据材料设计指南和/或最常见的方式了解执行此操作的标准方式。”
我不确定我的答案是材料设计还是常见的,但我已经完成了基于谷歌“照片”应用程序中的选择处理的 GridView。我已经对其进行了测试,并且知道它将包括一个突出显示的边框和一个“复选框”。
** 免责声明 **
我考虑过使用选择器,但如果您的视图滚动(请参阅this),这似乎会出现问题。此外,我使用了一个自定义复选框(实际上只是两个不同的可绘制对象),部分原因是. 此外,这个答案基本上只是在纵向模式下处理手机。需要添加更多来处理不同的配置(屏幕尺寸、方向等)
这里有很多,但就像我说的,我已经测试过了。整个项目已发布到GitHub。
1、在 MainActivity onCreate()
mList = new ArrayList<>();
// fill your list here
mAdapter = new GridAdapter(getApplicationContext(), R.layout.grid_item, mList);
GridView gridView = (GridView)findViewById(R.id.grid_view);
gridView.setAdapter(mAdapter);
gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
Log.d(TAG, "item clicked = " + i);
boolean isSelected = mList.get(i).isSelected();
mList.get(i).setSelected(!isSelected);
mAdapter.notifyDataSetChanged();
}
});
接下来,在您的适配器中覆盖 getView()(我使用的是 ArrayAdapter)
@NonNull
@Override
public View getView(int position, View convertView, @NonNull ViewGroup parent) {
RelativeLayout itemLayout;
GridItem gridItem = (GridItem)getItem(position);
// use existing Views when we can
if(convertView == null) {
LayoutInflater inflater = (LayoutInflater)
getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
itemLayout = (RelativeLayout) inflater.inflate(R.layout.grid_item, null);
} else {
itemLayout = (RelativeLayout) convertView;
}
// get your bitmap or list item etc. here
BitmapDrawable bitmap = gridItem.getBitmap();
ImageView imageView = (ImageView)itemLayout.findViewById(R.id.image_view);
imageView.setBackground(bitmap);
if(gridItem.isSelected()) {
final int PADDING = 16;
Log.d(TAG, "position " + position + " is selected");
itemLayout.findViewById(R.id.image_frame).setPadding(PADDING, PADDING, PADDING, PADDING);
itemLayout.findViewById(R.id.custom_check_box)
.setBackgroundResource(R.drawable.custom_check_box_selected);
} else {
Log.d(TAG, "postion " + position + " is NOT selected");
itemLayout.findViewById(R.id.image_frame).setPadding(0,0,0,0);
itemLayout.findViewById(R.id.custom_check_box)
.setBackgroundResource(R.drawable.custom_check_box_unselected);
}
return itemLayout;
}
这是 GridItem 类的核心,省略了 getter 和 setter。
public class GridItem {
private BitmapDrawable bitmap = null;
private boolean isSelected = false;
public GridItem(BitmapDrawable bitmap) {
this.bitmap = bitmap;
}
}
这就是Java。现在对于一些 xml
grid_item.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@color/colorAccent"
>
<FrameLayout
android:layout_width="140dp"
android:layout_height="140dp"
android:id="@+id/image_frame"
>
<!-- view for the main image -->
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:scaleType="center"
android:background="@android:color/white"
android:id="@+id/image_view"
/>
</FrameLayout>
<!-- view for the 'checkbox' in upper left corner -->
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="2dp"
android:src="@drawable/custom_check_box_unselected"
android:id="@+id/custom_check_box"
/>
</RelativeLayout>
这将进入 content_main.xml 或 activity_main.xml 等。
<GridView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:numColumns="2"
android:verticalSpacing="10dp"
android:horizontalSpacing="20dp"
android:stretchMode="columnWidth"
android:gravity="center"
android:id="@+id/grid_view"
>
</GridView>
现在为您的可绘制文件夹提供 2 个文件。
custom_check_box_unselected.xml
<vector xmlns:android="http://schemas.android.com/apk/res/android"
android:height="20dp"
android:width="20dp"
android:viewportWidth="400"
android:viewportHeight="400">
<!-- the outside box -->
<!-- top line & top left corner -->
<path android:pathData="M 340 30 H 62 c -20 0 -35 15 -35 35 "
android:strokeColor="#000000" android:strokeWidth="20" />
<!-- left line & bottom left corner -->
<path android:pathData="M 27 64 v271 c0 20 15 35 35 35 "
android:strokeColor="#000000" android:strokeWidth="20" />
<!-- bottom line & bottom right corner -->
<path android:pathData="M 60 370 h275 c20 0 35 -15 35 -35"
android:strokeColor="#000000" android:strokeWidth="20" />
<!-- right line & top right corner -->
<path android:pathData="M 370 336 v -271 c0 -20 -15 -35 -35 -35"
android:strokeColor="#000000" android:strokeWidth="20" />
</vector>
custom_check_box_selected.xml
<vector xmlns:android="http://schemas.android.com/apk/res/android"
android:height="20dp"
android:width="20dp"
android:viewportWidth="400"
android:viewportHeight="400">
<!-- the outside box -->
<path android:pathData="M 340 30 H 62 c -20 0 -35 15 -35 35
v271 c0 20 15 35 35 35
h275 c20 0 35 -15 35 -35
v -271 c0 -20 -15 -35 -35 -35 "
android:fillColor="#FDD835" android:strokeColor="#000000" android:strokeWidth="20" />
<!-- the check mark -->
<path android:pathData="M 140 320 l -100 -100 25 -30
l 75 75 l 190 -190
l 25 30 l -190 190"
android:fillColor="#000000" android:strokeColor="#000000" android:strokeWidth="2" />
</vector>
据我了解,当用户选中该复选框时,您想更改列表视图行颜色。
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
for (int j = 0; j < adapterView.getChildCount(); j++)
adapterView.getChildAt(j).setBackgroundColor(Color.TRANSPARENT);
// change the background color of the selected element
view.setBackgroundColor(Color.LTGRAY);
});
您可以根据您的要求使用您的逻辑来实现这种不断变化的颜色
您可以通过以下方式在列表视图中显示带有多选的复选框
在列表子 xml 中添加一个复选框并在 xml 中将其设置为可单击 false
android:clickable="false"
并为您的列表 OnItemSelectedListner 保留此
ArrayList<Integer> listPositionsSaveArray= new ArrayList<Integer>();
listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
CheckBox presentCheckBox=(CheckBox)view.findViewById(R.id.checkbox__list);
if(presentCheckBox.isChecked()){
presentCheckBox.setChecked(false);
listPositionsSaveArray.removeAll(Arrays.asList(position+1));
}
else{
presentCheckBox.setChecked(true);
listPositionsSaveArray.add(position+1);
}
}
});
listPositionsSaveArray
列表视图的所有选定位置现在都将在
这很简单。在布局文件中使用以下属性ListView
:
android:choiceMode="singleChoice"
android:listSelector="#666666"
如果您想以编程方式执行此操作,请尝试以下操作:
listView.setSelector(Drawable selector)
listView.setSelector(int resourceId)
listview.setChoiceMode(AbsListView.CHOICE_MODE_SINGLE);
如果要多选,请使用AbsListView.CHOICE_MODE_MULTIPLE
.