java如何在两个方法之间加载应用程序后立即调用方法？

Question

下面是我的java文件，我想运行

  DirectoryChooserDialog directoryChooserDialog = 

方法代替

openCamera();

一旦应用程序启动。 我尽了最大努力，每次启动应用程序时，`openCamera（）；首先启动而不是DirectoryChooserDialog DirectoryChooserDialog=。我知道我有任何办法可以做到这一点

public class MainActivity extends AppCompatActivity {
    public static final int MY_PERMISSIONS_REQUEST_CAMERA = 100;
    public static final String ALLOW_KEY = "ALLOWED";
    public static final String CAMERA_PREF = "camera_pref";
    private String m_chosenDir = "";
    private boolean m_newFolderEnabled = true;

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


                // Create DirectoryChooserDialog and register a callback
                DirectoryChooserDialog directoryChooserDialog =
                        new DirectoryChooserDialog(MainActivity.this,
                                new DirectoryChooserDialog.ChosenDirectoryListener()
                                {
                                    @Override
                                    public void onChosenDir(String chosenDir)
                                    {
                                        m_chosenDir = chosenDir;
                                        Toast.makeText(
                                                MainActivity.this, "Chosen directory: " +
                                                        chosenDir, Toast.LENGTH_LONG).show();
                                    }
                                });
                // Toggle new folder button enabling
                directoryChooserDialog.setNewFolderEnabled(m_newFolderEnabled);
                // Load directory chooser dialog for initial 'm_chosenDir' directory.
                // The registered callback will be called upon final directory selection.
                directoryChooserDialog.chooseDirectory(m_chosenDir);
                m_newFolderEnabled = ! m_newFolderEnabled;






        if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
            if (getFromPref(this, ALLOW_KEY)) {
                showSettingsAlert();
            } else if (ContextCompat.checkSelfPermission(this,
                    Manifest.permission.CAMERA)

                    != PackageManager.PERMISSION_GRANTED) {

                // Should we show an explanation?
                if (ActivityCompat.shouldShowRequestPermissionRationale(this,
                        Manifest.permission.CAMERA)) {
                    showAlert();
                } else {
                    // No explanation needed, we can request the permission.
                    ActivityCompat.requestPermissions(this,
                            new String[]{Manifest.permission.CAMERA},
                            MY_PERMISSIONS_REQUEST_CAMERA);
                }
            }
        } else {
            openCamera();
        }

    }
    publi

Answer 1

如果它直接跳入else并打开相机，If语句可能总是返回false：

if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED)

首先尝试在调试模式下运行项目，尝试并找出为什么它总是跳转到：

else {
  openCamera();
}

检查您的权限是否正确，以及if中的代码是否确实是您想要检查的