ActivityCompat.requestPermissions not showing dialog box

Here's an example of using requestPermissions():

First, define the permission (as you did in your post) in the manifest, otherwise, your request will automatically be denied:

<uses-permission android:name="android.permission.READ_PHONE_STATE" />

Next, define a value to handle the permission callback, in onRequestPermissionsResult():

private final int REQUEST_PERMISSION_PHONE_STATE=1;

Here's the code to call requestPermissions():

private void showPhoneStatePermission() {
    int permissionCheck = ContextCompat.checkSelfPermission(
            this, Manifest.permission.READ_PHONE_STATE);
    if (permissionCheck != PackageManager.PERMISSION_GRANTED) {
        if (ActivityCompat.shouldShowRequestPermissionRationale(this,
                Manifest.permission.READ_PHONE_STATE)) {
            showExplanation("Permission Needed", "Rationale", Manifest.permission.READ_PHONE_STATE, REQUEST_PERMISSION_PHONE_STATE);
        } else {
            requestPermission(Manifest.permission.READ_PHONE_STATE, REQUEST_PERMISSION_PHONE_STATE);
        }
    } else {
        Toast.makeText(MainActivity.this, "Permission (already) Granted!", Toast.LENGTH_SHORT).show();
    }
}

First, you check if you already have permission (remember, even after being granted permission, the user can later revoke the permission in the App Settings.)

And finally, this is how you check if you received permission or not:

@Override
public void onRequestPermissionsResult(
        int requestCode,
        String permissions[],
        int[] grantResults) {
    switch (requestCode) {
        case REQUEST_PERMISSION_PHONE_STATE:
            if (grantResults.length > 0
                    && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                Toast.makeText(MainActivity.this, "Permission Granted!", Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(MainActivity.this, "Permission Denied!", Toast.LENGTH_SHORT).show();
            }
    }
}

private void showExplanation(String title,
                             String message,
                             final String permission,
                             final int permissionRequestCode) {
    AlertDialog.Builder builder = new AlertDialog.Builder(this);
    builder.setTitle(title)
            .setMessage(message)
            .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                    requestPermission(permission, permissionRequestCode);
                }
            });
    builder.create().show();
}

private void requestPermission(String permissionName, int permissionRequestCode) {
    ActivityCompat.requestPermissions(this,
            new String[]{permissionName}, permissionRequestCode);
}

I had the same issue and it turned out to be due to the manifest merger tool pulling in an android:maxSdkVersion attribute from a dependency.

To view the actual permissions you're requesting in your APK you can use the aapt tool, like this:

/path/to/android-sdk/build-tools/version/aapt d permissions /path/to/your-apk.apk

in my case, it printed:

uses-permission: name='android.permission.WRITE_EXTERNAL_STORAGE' maxSdkVersion='18'

even though I hadn't specified a maxSdkVersion in my manifest. I fixed this issue by changing <uses-permission> in my manifest to:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" tools:remove="android:maxSdkVersion"/>

(where the tools namespace is http://schemas.android.com/tools)