一起Talk Android吧（第二百三十四回：Android中的数据存储之ContentProvider二）

本文主要是介绍一起Talk Android吧（第二百三十四回：Android中的数据存储之ContentProvider二），希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

各位看官们大家好，上一回中咱们说的是Android中数据存储之ContentProvider的例子,这一回咱们继续说该例子。闲话休提，言归正转。让我们一起Talk Android吧！

看官们，我们在上一回中介绍了如何通过ContentProvider读取联系人模块中的数据，下面是完整的代码，请大家参考：

package com.example.talk8.blogappall;import android.Manifest;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.provider.ContactsContract;
import android.support.annotation.NonNull;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;public class ActivityContentProvider extends AppCompatActivity {private static final String TAG = "DataStorage";private Button mReadContact;private TextView mName;private TextView mPhone;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_content_provider);mReadContact = (Button)findViewById(R.id.read_contact);mName = (TextView)findViewById(R.id.name_contact);mPhone = (TextView)findViewById(R.id.phone_contact);mReadContact.setOnClickListener(v -> CheckPermisson());}//通过ContentProvider读取联系人中数据public void ReadContact() {Cursor cursor = null;Log.i(TAG, "ReadContact: ");try {cursor = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI,null , null, null);if(cursor != null) {while (cursor.moveToNext()) {Log.i(TAG, "ReadContact: get Cursor");String name = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));String number = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));mName.setText("Name: "+name);mPhone.setText("PhoneNumber: "+number);}}}catch (Exception e) {Log.i(TAG, "ReadContact:  Exception");e.printStackTrace();}finally {if(cursor != null) {cursor.close();}}}//访问联系人需要进行权限申请，而且manifest文件中也需要添加权限private void CheckPermisson() {if (ContextCompat.checkSelfPermission(this, Manifest.permission.READ_CONTACTS)!= PackageManager.PERMISSION_GRANTED) {Log.i(TAG, "CheckPermisson: ");ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_CONTACTS}, 1);}else {Log.i(TAG, "CheckPermisson:  permission is ok");ReadContact();}}//用户选择权限后，依据用户选择来读取数据@Overridepublic void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {super.onRequestPermissionsResult(requestCode, permissions, grantResults);switch (requestCode) {case 1:if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {Log.i(TAG, "onRequestPermissionsResult: Permisson Approved");ReadContact();}else {Log.i(TAG, "onRequestPermissionsResult: Permisson Rejected");Toast.makeText(this, "Read Contact Permisssion denied", Toast.LENGTH_LONG);}default:break;}}
}