实现ContentResolver对ContentProvider内容的修改

来源：互联网发布：淘宝网针织衫外套编辑：程序博客网时间：2024/05/17 01:26

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ContentResolver的实现没有ContentProvider复杂，不需要配置清单文件（除访问系统的权限要添加外，自己模拟底层的就不用了）不多说了直接上代码

MainActivity的布局文件

<EditText        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:hint="ID"        android:id="@+id/et_main_id"/>    <Button        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="获取数据"        android:id="@+id/bt_mainsss_button"        />    <ListView        android:layout_width="match_parent"        android:layout_height="match_parent"        android:id="@+id/lv_list"        ></ListView>

由于长按修改和Listview自己定义的布局。所以也加上来

先上长按修改的布局

<TextView        android:id="@+id/tv_dialog_list_id"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:textSize="30sp" />    <EditText        android:id="@+id/et_dialog_list_name"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:textSize="30sp" />    <EditText        android:id="@+id/et_dialog_list_age"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:textSize="30sp" />    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content">        <Button            android:id="@+id/btn_dialog_list_ok"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="确定修改" />        <Button            android:id="@+id/btn_dialog_list_nook"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="取消修改" />    </LinearLayout>

然后是ListView的布局文件

 <TextView        android:id="@+id/tv_list_id"        android:layout_width="0dp"        android:layout_height="wrap_content"        android:layout_weight="1" />    <TextView        android:id="@+id/tv_list_name"        android:layout_width="0dp"        android:layout_height="wrap_content"        android:layout_weight="1" />    <TextView        android:id="@+id/tv_list_age"        android:layout_width="0dp"        android:layout_height="wrap_content"        android:layout_weight="1" />

MainActivity的主要代码

public class MainActivity extends AppCompatActivity {    private EditText et_main_id;    private Button bt_mainsss_button;    private Uri uri;    private ContentResolver cr;    private ListView lv_list;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        et_main_id = (EditText) findViewById(R.id.et_main_id);        bt_mainsss_button = (Button) findViewById(R.id.bt_mainsss_button);        lv_list = (ListView) findViewById(R.id.lv_list);        //获得内容访问者        cr = getContentResolver();        //点击事件        bt_mainsss_button.setOnClickListener(new View.OnClickListener() {            private SimpleCursorAdapter simpleCursorAdapter;            @Override            public void onClick(View view) {                if (TextUtils.isEmpty(et_main_id.getText().toString())) {                    //查询所有                    uri = Uri.parse("content://com.example.contentprovider.PERSON/student");                } else {                    //查询单个                    String id = et_main_id.getText().toString();                    uri = Uri.parse("content://com.example.contentprovider.PERSON/student/" + id);                }                Cursor cursor = cr.query(uri, null, null, null, null);                //SimleCursorAdapter                while (cursor.moveToNext()) {                    int id = cursor.getInt(cursor.getColumnIndex("_id"));                    String name = cursor.getString(cursor.getColumnIndex("name"));                    int age = cursor.getInt(cursor.getColumnIndex("age"));                    Log.i("test", id + " " + name + " " + age);//                        simpleCursorAdapter.changeCursor(cursor);                }                simpleCursorAdapter = new SimpleCursorAdapter(MainActivity.this, R.layout.item_list, cursor, new String[]{"_id", "name", "age"}, new int[]{R.id.tv_list_id, R.id.tv_list_name, R.id.tv_list_age});                lv_list.setAdapter(simpleCursorAdapter);            }        });        lv_list.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {            private EditText et_dialog_list_name;            private EditText et_dialog_list_age;            private TextView tv_dialog_list_id;            @Override            public boolean onItemLongClick(AdapterView<?> adapterView, View view, int i, long l) {                LinearLayout root = (LinearLayout) view;                String id = ((TextView) root.findViewById(R.id.tv_list_id)).getText().toString();                String name = ((TextView) root.findViewById(R.id.tv_list_name)).getText().toString();                String age = ((TextView) root.findViewById(R.id.tv_list_age)).getText().toString();                final AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);                final AlertDialog alertDialog = builder.create();                //点击空白处，不取消对话框                alertDialog.setCancelable(false);                View v = View.inflate(MainActivity.this, R.layout.dialog, null);                tv_dialog_list_id = (TextView) v.findViewById(R.id.tv_dialog_list_id);                et_dialog_list_name = (EditText) v.findViewById(R.id.et_dialog_list_name);                et_dialog_list_age = (EditText) v.findViewById(R.id.et_dialog_list_age);                tv_dialog_list_id.setText(id);                et_dialog_list_name.setText(name);                et_dialog_list_age.setText(age);                ((Button) v.findViewById(R.id.btn_dialog_list_ok)).setOnClickListener(new View.OnClickListener() {                    @Override                    public void onClick(View view) {                        String _id=tv_dialog_list_id.getText().toString();                        String _name=et_dialog_list_name.getText().toString();                        String _age=et_dialog_list_age.getText().toString();                        Toast.makeText(MainActivity.this, "_id"+_id+"_name"+_name+"_age"+_age, Toast.LENGTH_SHORT).show();//如果要实现修改后刷新，只要在关闭前在查一次就行                        ContentValues values=new ContentValues();                        values.put("name",""+_name);                        values.put("age",""+_age);                        cr.update(uri,values,"_id=?",new String[]{_id});                        alertDialog.dismiss();                    }                });                ((Button) v.findViewById(R.id.btn_dialog_list_nook)).setOnClickListener(new View.OnClickListener() {                    @Override                    public void onClick(View view) {                        //关闭当前对话框                        alertDialog.dismiss();                    }                });                alertDialog.setView(v);                alertDialog.show();                return true;            }        });    }}

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