在我的应用中检查 WRITE_SECURE_SETTINGS 权限的问题

Question

我对 Android 和 Javascript 还很陌生。但是，我正在通过观看教程和提问来积极学习。现在，我正在尝试编写一个更改某些系统值的应用程序。我知道这只能通过授予我的应用 WRITE_SECURE_SETTINGS 权限来完成。通过我的研究，我意识到我不能在清单文件本身中声明权限。显然，唯一值得尊重的答案是检查用户是否已通过 ADB 授予权限。我找不到与此主题相关的任何内容，我希望你们能帮助我就如何正确执行此操作得出结论。到目前为止，这是我拥有的代码。

package com.datastream.settingschanger;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {

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

    String requiredPermission = "android.permission.WRITE_SECURE_SETTINGS";
    int checkVal = getContext().checkCallingOrSelfPermission(requiredPermission);
    if (checkVal == PackageManager.PERMISSION_GRANTED) {
    }
    Toast.makeText(getActivity(), "WRITE_SECURE_SETTINGS has been granted to the application. You may now continue!",
            Toast.LENGTH_LONG).show();

    if (checkVal == PackageManager.PERMISSION_DENIED) {
    }
    Toast.makeText(getActivity(), "WRITE_SECURE_SETTINGS has not been granted to the application. Please grant access to continue.",
            Toast.LENGTH_LONG).show();
}
}

但是，当我在 Android Studio 中运行它时，我会收到以下错误：

error: cannot find symbol method getContext()
error: cannot find symbol method getActivity()
error: cannot find symbol method getActivity()

谁能帮我解决这些错误？我不知道如何解决这个问题。谢谢！

Answer 1

Fragment中使用getContext()和getActivity()方法得到Context

去掉getContext()和getActivity()并使用this和MainActivity.this得到Context 在你的活动中

使用这个

int checkVal = checkCallingOrSelfPermission(requiredPermission);

而不是这个

int checkVal = getContext().checkCallingOrSelfPermission(requiredPermission);

示例代码

public class MainActivity extends AppCompatActivity {

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

    String requiredPermission = "android.permission.WRITE_SECURE_SETTINGS";
    int checkVal = checkCallingOrSelfPermission(requiredPermission);
    if (checkVal == PackageManager.PERMISSION_GRANTED) {
    }
    Toast.makeText(this, "WRITE_SECURE_SETTINGS has been granted to the application. You may now continue!",
            Toast.LENGTH_LONG).show();

    if (checkVal == PackageManager.PERMISSION_DENIED) {
    }
    Toast.makeText(this, "WRITE_SECURE_SETTINGS has not been granted to the application. Please grant access to continue.",
            Toast.LENGTH_LONG).show();
}
}