Android從內容提供者中獲取聯繫人

第一步 申請配置權限

<uses-permission android:name="android.permission.READ_CONTACTS"/>

第二步 在佈局文件中添加ListView用來顯示獲取到的聯繫人

   <ListView
        android:id="@+id/lv_contacts"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

第三步 初始化ListView

  private void initView() {
        mLvContacts = findViewById(R.id.lv_contacts);
        mAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_expandable_list_item_1,mContacts);
        mLvContacts.setAdapter(mAdapter);
    }

第四步 動態申請權限

4.1 檢查是否有權限

   private boolean checkPermission() {
        return ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_CONTACTS) == PackageManager.PERMISSION_GRANTED;
    }

4.2 如果有權限，則獲取聯繫人並更新界面

   private void contactsFromContentProvider() {
        Cursor cursor = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, null, null, null);
        while (cursor.moveToNext()){
            String name = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
            String phoneNumber = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
            mContacts.add(name+"\n"+phoneNumber);
        }
        mAdapter.notifyDataSetChanged();
        cursor.close();
    }

4.3 如果沒有權限，則動態申請權限

   private void requestPermission() {
        ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.READ_CONTACTS},REQUEST_READ_CONTACTS_PERMISSION_CODE);
    }

4.4 申請權限回調邏輯

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if(requestCode == REQUEST_READ_CONTACTS_PERMISSION_CODE){
            if (grantResults.length>0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
                contactsFromContentProvider();
            }else{
                Toast.makeText(this,"您沒有讀取聯繫人權限！",Toast.LENGTH_SHORT).show();
            }
        }
    }