MainActivity.java

package com.halzhang.android.examples.accessibilityexample;

import android.content.Intent;
import android.os.Bundle;
import android.provider.Settings;
import android.support.v7.app.AppCompatActivity;
import android.view.View;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.btn_open_setting).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(Settings.ACTION_ACCESSIBILITY_SETTINGS);
                startActivity(intent);
            }
        });
    }
}