android studio listview长按删除 _ListView

【android studio listview长按删除】古人学问无遗力，少壮工夫老始成。这篇文章主要讲述android studio listview长按删除相关的知识，希望能为你提供帮助。
activity_main.xml 的代码

< ?xml version="1.0" encoding="utf-8"?> < android.support.constraint.ConstraintLayout 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="wrap_content" android:layout_height="match_parent" tools:context=".MainActivity"> < TextView android:id="@+id/textView5" android:layout_width="45dp" android:layout_height="17dp" android:layout_marginLeft="4dp" android:layout_marginStart="4dp" android:layout_marginTop="16dp" android:text="班级：" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toTopOf="parent" /> < TextView android:id="@+id/textView6" android:layout_width="47dp" android:layout_height="wrap_content" android:layout_marginLeft="4dp" android:layout_marginStart="4dp" android:layout_marginTop="29dp" android:text="学号：" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@+id/textView5" /> < EditText android:id="@+id/editText3" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="12dp" android:layout_marginStart="12dp" android:ems="10" android:inputType="textPersonName" app:layout_constraintStart_toEndOf="@+id/textView5" tools:layout_editor_absoluteY="0dp" /> < EditText android:id="@+id/editText4" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="12dp" android:layout_marginStart="12dp" android:ems="10" android:inputType="textPersonName" app:layout_constraintStart_toEndOf="@+id/textView6" app:layout_constraintTop_toBottomOf="@+id/editText3" /> < TextView android:id="@+id/textView7" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="4dp" android:layout_marginStart="4dp" android:layout_marginTop="28dp" android:text="姓名：" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@+id/textView6" /> < EditText android:id="@+id/editText5" android:layout_width="wrap_content" android:layout_height="45dp" android:layout_marginLeft="16dp" android:layout_marginStart="16dp" android:ems="10" android:inputType="textPersonName" app:layout_constraintStart_toEndOf="@+id/textView7" app:layout_constraintTop_toBottomOf="@+id/editText4" /> < Button android:id="@+id/button" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="4dp" android:layout_marginStart="4dp" android:layout_marginTop="8dp" android:text="添加" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@+id/editText5" /> < ListView android:id="@+id/android:list" android:layout_width="wrap_content" android:layout_height="313dp" app:layout_constraintBottom_toBottomOf="parent" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintHorizontal_bias="0.0" app:layout_constraintStart_toStartOf="parent" app:layout_constraintTop_toBottomOf="@+id/button" app:layout_constraintVertical_bias="0.0" /> < /android.support.constraint.ConstraintLayout>

item.xml 这是listview中的项

< ?xml version="1.0" encoding="utf-8"?> < android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/relativeLayout1" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> < LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="horizontal"> < TextView android:id="@+id/grade" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_weight="1" android:text= "班级" android:textSize="20sp" android:textColor="#0b0a0b" tools:layout_editor_absoluteX="46dp" android:paddingLeft="20dp" tools:layout_editor_absoluteY="0dp" /> < TextView android:id="@+id/studentId" android:layout_width="wrap_content" android:layout_height="27dp" android:layout_weight="1" android:text="学号" android:textSize="20sp" android:textColor="#0b0a0b" tools:layout_editor_absoluteX="89dp" android:paddingLeft="20dp" tools:layout_editor_absoluteY="0dp" /> < TextView android:id="@+id/name" android:layout_width="wrap_content" android:layout_height="27dp" android:layout_alignParentLeft="true" android:layout_alignParentTop="true"android:layout_weight="1" android:text="姓名" android:textColor="#0b0a0b" android:paddingLeft="20dp" android:textSize="20sp" /> < /LinearLayout> < /android.support.constraint.ConstraintLayout>

strings.xml一些字符串资源，后来嫌麻烦，直接硬编码了

< resources> < string name="app_name"> deletetry1< /string> < string name="grade"> 计算机151< /string> < string name="score"> 成绩< /string> < string name="banji"> 班级< /string> < string name="stid"> 学号< /string> < string name="name1"> 王菲< /string> < string name="name2"> 张宇< /string> < string name="name3"> 张学友< /string> < string name="name4"> 刘德华< /string> < /resources>

information类，这个类用来管理学生信息

package com.example.cie.deletetry1; public class Information { private String mGrade; private int mStudentId; private String mName; public Information(String grade, int studentId, String mName) { mGrade = grade; mStudentId = studentId; this.mName = mName; }public String getGrade() { return mGrade; }public void setGrade(String grade) { mGrade = grade; }public int getStudentId() { return mStudentId; }public void setStudentId(int studentId) { mStudentId = studentId; }public String getName() { return mName; }public void setName(String mName) { this.mName = mName; } }

mainActivity.java

package com.example.cie.deletetry1; import android.app.ListActivity; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.ContextMenu; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.*; import android.widget.Button; import android.widget.EditText; import android.widget.ListView; import android.widget.SimpleAdapter; import android.widget.Toast; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; public class MainActivity extends ListActivity {private Button mAddButton; private EditText grade, studentid, name; private Information[] mStudInfo = new Information[]{ new Information("计算机151", 2014012543, "张宇"), new Information("计算机151", 2014012544, "刘德华"), new Information("计算机151", 2014012545, "张学友"), }; private ListView listview; List< Map< String, Object> > mlistItems; Map< String, Object> mmap; //定义一个simpleAdapter，供列表项使用 SimpleAdapter mSimpleAdapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); listview = (ListView) findViewById(android.R.id.list); //为所有的listview的item注册contextMenu this.registerForContextMenu(listview); mlistItems = new ArrayList< Map< String, Object> > (); for (int i = 0; i < mStudInfo.length; i++) { mmap = new HashMap< String, Object> (); mmap.put("grade", mStudInfo[i].getGrade()); mmap.put("studentId", mStudInfo[i].getStudentId()); mmap.put("name", mStudInfo[i].getName()); mlistItems.add(mmap); } mSimpleAdapter = new SimpleAdapter(this, mlistItems, R.layout.item, new String[]{"grade", "studentId", "name"}, new int[]{R.id.grade, R.id.studentId, R.id.name}); listview.setAdapter(mSimpleAdapter); //添加对象 mAddButton = (Button) findViewById(R.id.button); grade = (EditText) findViewById(R.id.editText3); studentid = (EditText) findViewById(R.id.editText4); name = (EditText) findViewById(R.id.editText5); mAddButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { mmap = new HashMap< String, Object> (); mmap.put("grade", grade.getText()); mmap.put("studentId", studentid.getText()); mmap.put("name", name.getText()); mlistItems.add(mmap); mSimpleAdapter.notifyDataSetChanged(); } }); }@Override public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) { menu.setHeaderTitle("选择操作"); menu.add(0, 1, Menu.NONE, "删除"); }@Override public boolean onContextItemSelected(MenuItem item) { AdapterContextMenuInfo menuInfo = (AdapterContextMenuInfo) item.getMenuInfo(); switch (item.getItemId()) { case 1: //删除 int pos = (int) listview.getAdapter().getItemId(menuInfo.position); if (mlistItems.remove(pos) != null) { System.out.println("success"); } else { System.out.println("failed"); } mSimpleAdapter.notifyDataSetChanged(); Toast.makeText(getBaseContext(), "删除此项", Toast.LENGTH_SHORT).show(); break; default: //标记 return super.onContextItemSelected(item); } return true; }}