android中关于call拨号功能的实现方法

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
>
<Button
  android:id="@+id/btn_dial"
  android:text="Dial"
  android:layout_width="match_parent"
  android:layout_height="wrap_content" />
<Button
  android:id="@+id/call"
  android:text="call"
  android:layout_width="match_parent"
  android:layout_height="wrap_content" />
</LinearLayout>

package com.cnblogs.dialandcall;

import android.Manifest;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;
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.view.View;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

  private Button btn_dial;
  private Button btn_call;
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    btn_call = (Button)findViewById(R.id.btn_call);
    btn_call.setOnClickListener(this);

    btn_dial = (Button)findViewById(R.id.btn_dial);
    btn_dial.setOnClickListener(this);
  }

  @Override
  public void onClick(View v) {
    switch (v.getId()){
      case R.id.btn_call:
        onCall();
        break;
      case R.id.btn_dial:
        Intent dialIntent = new Intent(Intent.ACTION_DIAL);
        dialIntent.setData(Uri.parse("tel:10086"));
        startActivity(dialIntent);
        break;
    }
  }

  private void onCall() {
    int permissionCheck = ContextCompat.checkSelfPermission(this, Manifest.permission.CALL_PHONE);
    if(permissionCheck!= PackageManager.PERMISSION_GRANTED){
      ActivityCompat.requestPermissions(this,new String[]{Manifest.permission.CALL_PHONE}, Integer.parseInt("001"));
    }
    else{
      startActivity(new Intent(Intent.ACTION_CALL).setData(Uri.parse("tel:10086")));
    }
  }

  @Override
  public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    switch (requestCode){
      case 001:
        if(grantResults.length>0&&(grantResults[0]==PackageManager.PERMISSION_GRANTED)){
          onCall();
        }
        else {
          Toast.makeText(getBaseContext(),"You Need Allow The Permission To Run This App",Toast.LENGTH_SHORT).show();
        }
        break;
    }
  }
}