안드로이드 권한 확인 소스코드(다른 앱 위에 그리기, 시스템을 변경할 수 있는 앱, 접근성 설정)

자바 : 

@Override
    protected void onResume() {
        super.onResume();

        BitSet bitSet = new BitSet();

        if ( checkDrawOverlayPermission(getApplicationContext()) ){
            bitSet.set(0);
            overlayPermissionButton.setText("완료");
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                overlayPermissionButton.setBackgroundTintList(getResources().getColorStateList(R.color.colorPrimaryDark));
            }
        }
        if ( checkWriteSettingPermission() ){
            bitSet.set(1);
            writeSettingPermissiononButton.setText("완료");
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                writeSettingPermissiononButton.setBackgroundTintList(getResources().getColorStateList(R.color.colorPrimaryDark));
            }
        }
        if( checkAccessibilityService(getApplicationContext()) ) {
            bitSet.set(2);
            accessibilityPermissionButton.setText("완료");
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                accessibilityPermissionButton.setBackgroundTintList(getResources().getColorStateList(R.color.colorPrimaryDark));
            }
        }

        if(bitSet.get(0) && bitSet.get(1) && bitSet.get(2)){
            startActivity(new Intent(getApplicationContext(), Activity_Main.class)
                    .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK|Intent.FLAG_ACTIVITY_NO_ANIMATION)
            );
            finish();
        }
    }

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

        if(getSupportActionBar() != null){
            getSupportActionBar().setTitle("권한");
        }

        overlayPermissionButton = findViewById(R.id.button_overlay_permission);
        writeSettingPermissiononButton = findViewById(R.id.button_write_setting_permission);
        accessibilityPermissionButton = findViewById(R.id.button_accessibility_permission);


        overlayPermissionButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if( ! overlayPermissionButton.getText().equals("완료") ){
                    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
                        startActivity(
                                new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION, Uri.parse("package:" + getPackageName()))
                                        .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
                        );
                    }
                }
            }
        });

        writeSettingPermissiononButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if( ! writeSettingPermissiononButton.getText().equals("완료") ) {
                    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {
                        startActivity(
                                new Intent(Settings.ACTION_MANAGE_WRITE_SETTINGS)
                                        .setData(Uri.parse("package:" + getPackageName()))
                                        .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
                        );
                    }
                }
            }
        });

        accessibilityPermissionButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startActivity(
                        new Intent(Settings.ACTION_ACCESSIBILITY_SETTINGS)
                                .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
                );
            }
        });
    }

    //오버레이 권한 확인
    //마시멜로 이상부터만 가능
    public boolean checkDrawOverlayPermission(Context context) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (Settings.canDrawOverlays(context)) {
                return true;
            } else {
                return false;
            }
        }
        else{
            return true;
        }
    }

    //시스템을 변경 할 수 있는 권한 으로 넘겨주는 부분
    //마시멜로 이상부터만 가능
    public boolean checkWriteSettingPermission() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            if (Settings.System.canWrite(getApplicationContext())) {
                return true;
            }
            else{
                return false;
            }
        }
        else {
            return true;
        }
    }

    // 접근성 권한이 있는지 없는지 확인하는 부분
    private boolean checkAccessibilityService(Context mContext) {
        int accessibilityEnabled = 0;
        final String service = getPackageName() + "/" + Service_AppListener.class.getCanonicalName();
        try {
            accessibilityEnabled = Settings.Secure.getInt(
                    mContext.getApplicationContext().getContentResolver(),
                    android.provider.Settings.Secure.ACCESSIBILITY_ENABLED);
        } catch (Settings.SettingNotFoundException e) {
            e.printStackTrace();
//            Log.e(TAG, "Error finding setting, default accessibility to not found: " + e.getMessage());
        }
        TextUtils.SimpleStringSplitter mStringColonSplitter = new TextUtils.SimpleStringSplitter(':');

        if (accessibilityEnabled == 1) {
            String settingValue = Settings.Secure.getString(
                    mContext.getApplicationContext().getContentResolver(),
                    Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES);

            if (settingValue != null) {
                mStringColonSplitter.setString(settingValue);

                while (mStringColonSplitter.hasNext()) {
                    String accessibilityService = mStringColonSplitter.next();

                    if (accessibilityService.equalsIgnoreCase(service)) {
                        return true;
                    }
                }
            }
        }

        return false;
    }

xml : 

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".Activity_Permission"
    tools:ignore="HardcodedText"
    >

    <TextView
        android:id="@+id/textView13"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        android:text='1. "권한 허용하기" 버튼을 눌러 다른 앱 위에 표시되는 앱 권한을 허용해주쉐요 : )'
        android:textColor="@color/textColorBlack"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        />

    <Button
        android:id="@+id/button_overlay_permission"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:text="권한 허용하기"
        android:textColor="#fff"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView13"
        android:textStyle="bold"
        />

    <TextView
        android:id="@+id/textView15"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="16dp"
        android:text='2. "권한 허용하기" 버튼을 눌러 시스템을 변경할 수 있는 앱 권한을 허용해주세요 : )'
        android:textColor="@color/textColorBlack"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button_overlay_permission" />

    <Button
        android:id="@+id/button_write_setting_permission"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:text="권한 허용하기"
        android:textStyle="bold"
        android:textColor="#fff"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView15" />

    <TextView
        android:id="@+id/textView16"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="16dp"
        android:text='3. "접근성 설정" 버튼을 누르고 - "네비 자동실행"을 찾아서 클릭 후 - 권한을 활성화 시켜주세요 : )'
        android:textColor="@color/textColorBlack"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/button_write_setting_permission" />

    <Button
        android:id="@+id/button_accessibility_permission"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:text="접근성 설정"
        android:textColor="#fff"
        android:textStyle="bold"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textView16" />
</android.support.constraint.ConstraintLayout>