ZXING

import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;

import com.xys.libzxing.zxing.activity.CaptureActivity;
import com.xys.libzxing.zxing.encoding.EncodingUtils;

public class MainActivity extends AppCompatActivity {

    private static final int REQUESTCODE = 0;//请求码
    private TextView content;
    private EditText editText;
    private ImageView imageView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Button start = (Button) findViewById(R.id.start);//开始扫描
        Button create = (Button) findViewById(R.id.create);//生成二维码
        //扫描内容
        content = (TextView) findViewById(R.id.content);
        //输入框
        editText = (EditText) findViewById(R.id.editText);
        //二维码图片
        imageView = (ImageView) findViewById(R.id.imageView);


        start.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(MainActivity.this, CaptureActivity.class);
                startActivityForResult(intent,REQUESTCODE);
            }
        });

        create.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String s = editText.getText().toString();
                Bitmap qrCode = EncodingUtils.createQRCode(s, 600, 600, null);
                imageView.setImageBitmap(qrCode);
            }
        });

    }
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (resultCode == RESULT_OK) {
            Bundle extras = data.getExtras();
            String result = extras.getString("result");
            content.setText(result);
        }
    }

}