android studio 中的运行时权限

Question

我创建了一个可以发送消息和拨打电话的应用程序（仅在授予权限的情况下）

我已经尝试通过手动允许访问我的短信和电话的权限来发送短信或使用我的手机设置拨打电话

所以这是我的代码（PhoneApp.java）

package com.example.phone;

import android.Manifest;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.telephony.SmsManager;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;


public class PhoneApp extends AppCompatActivity {
    private static final int MY_PERMISSIONS_REQUEST_SEND_SMS =0 ;
    private Toolbar mTopToolbar;
    private static final int REQUEST_PHONE_CALL = 1;
    Button sendBtn;
    EditText txtMessage;
    EditText edittext1;
    Button button1;
    String phoneNo;
    String message;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.myphone);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        //Getting the edittext and button instance
        edittext1=(EditText)findViewById(R.id.editText);
        button1=(Button)findViewById(R.id.btnCall);
        sendBtn = (Button) findViewById(R.id.btnSendSMS);
        txtMessage = (EditText) findViewById(R.id.editText2);

        //Performing action on button click
        button1.setOnClickListener(new OnClickListener(){

            @Override
            public void onClick(View view) {
                makeCall();
            }



        });

        sendBtn.setOnClickListener(new View.OnClickListener() {
            public void onClick(View view) {
                SmsManager smsManager = SmsManager.getDefault();
                smsManager.sendTextMessage(
                        edittext1.getText().toString(),
                        null,
                        txtMessage.getText().toString(),
                        null,
                        null);

                Toast.makeText(getApplicationContext(), "SMS sent.",
                        Toast.LENGTH_LONG).show();
            }
        });

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.SEND_SMS) != PackageManager.PERMISSION_GRANTED) {
            Log.d("PLAYGROUND", "Permission is not granted, requesting");
            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.SEND_SMS}, MY_PERMISSIONS_REQUEST_SEND_SMS);
            sendBtn.setEnabled(false);
        } else {
            Log.d("PLAYGROUND", "Permission is granted");
        }
    }

    Intent intent = new Intent(Intent.ACTION_CALL);

    protected void makeCall() {
        String number=edittext1.getText().toString();
        intent.setData(Uri.parse("tel:"+number));
        if (ContextCompat.checkSelfPermission(PhoneApp.this,
                Manifest.permission.CALL_PHONE)
                != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(PhoneApp.this,
                    new String[]{Manifest.permission.CALL_PHONE},REQUEST_PHONE_CALL);
        }
        else
        {
            startActivity(intent);
        }
    }



    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }
    @Override
    public void onRequestPermissionsResult(int requestCode,String permissions[], int[] grantResults) {
        switch (requestCode) {

            case REQUEST_PHONE_CALL: {
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    Toast.makeText(getApplicationContext(), "Calling....",
                            Toast.LENGTH_LONG).show();
                    startActivity(intent);
                }
                else
                {
                    Toast.makeText(getApplicationContext(),
                            "Unable to connect", Toast.LENGTH_LONG).show();
                    return;
                }
                return;
            }
            case MY_PERMISSIONS_REQUEST_SEND_SMS: {
                if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                    Log.d("PLAYGROUND", "Permission has been granted");
                    Toast.makeText(getApplicationContext(),
                            "You can send SMS", Toast.LENGTH_LONG).show();
                    sendBtn.setEnabled(true);
                } else {
                    Log.d("PLAYGROUND", "Permission has been denied or request cancelled");
                    Toast.makeText(getApplicationContext(),
                            "Unable to connect", Toast.LENGTH_LONG).show();
                    sendBtn.setEnabled(false);
                }
            }
        }
    }

}

XML 代码 (myphone.xml)

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context=".PhoneApp">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:minHeight="?attr/actionBarSize"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:titleTextColor="@android:color/white"
        android:background="?attr/colorPrimary">
    </android.support.v7.widget.Toolbar>



    <EditText
        android:id="@+id/editText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:hint="@string/phone_number"
        android:layout_alignParentRight="true"
        android:layout_marginTop="88dp"
        android:layout_marginRight="109dp"
        android:ems="10" />

    <EditText
        android:id="@+id/editText2"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editText"
        android:layout_alignLeft="@+id/editText"
        android:layout_marginLeft="6dp"
        android:layout_marginTop="65dp"
        android:hint="@string/type_your_message"
        android:ems="10"
        android:inputType="textMultiLine" />
    <Button
        android:id="@+id/btnSendSMS"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="90dp"
        android:layout_below="@+id/editText2"
        android:layout_marginTop="60dp"
        android:text="Send Sms" />

    <Button
        android:id="@+id/btnCall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_marginTop="302dp"
        android:layout_marginLeft="270dp"
        android:text="Call" />

</RelativeLayout>

这是我的设计：

我希望我的应用程序只有在我点击“发送短信”按钮时才请求许可，而不是每次我进入上述页面时我的应用程序都会请求许可（不点击“发送短信”按钮）。 但这不是按钮的情况。 它工作得很好（只有在我点击“呼叫”按钮后才请求许可）。

如果您通过以代码段的形式提供解决方案来帮助我解决这个问题，那就太好了。 对不起，我的英语不好。 提前致谢！

Answer 1

解决方案很简单，只需将您的 onCreate() 更改为：

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.myphone);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    //Getting the edittext and button instance
    edittext1 = (EditText) findViewById(R.id.editText);
    button1 = (Button) findViewById(R.id.btnCall);
    sendBtn = (Button) findViewById(R.id.btnSendSMS);
    txtMessage = (EditText) findViewById(R.id.editText2);

    //Performing action on button click
    button1.setOnClickListener(this::makeCall());

    sendBtn.setOnClickListener((view) - >{
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.SEND_SMS) != PackageManager.PERMISSION_GRANTED) {
            Log.d("PLAYGROUND", "Permission is not granted, requesting");
            ActivityCompat.requestPermissions(this, new String[] {
                Manifest.permission.SEND_SMS
            },
            MY_PERMISSIONS_REQUEST_SEND_SMS);
        } else {
            Log.d("PLAYGROUND", "Permission is granted");
            SmsManager smsManager = SmsManager.getDefault();
            smsManager.sendTextMessage(
            edittext1.getText().toString(), null, txtMessage.getText().toString(), null, null);

            Toast.makeText(getApplicationContext(), "SMS sent.", Toast.LENGTH_LONG).show();
        }
    });
}

问题是您正在请求在 onCreate() 函数中发送消息的权限，但要使其按需要工作，您必须向按钮的 onClick() 侦听器请求权限。

就在这个主题上，我通过更改为 lambda 函数来格式化您的代码。

希望这能解决您的问题。 如果您愿意，我很乐意解释我更改的代码的任何部分。