Android--AlertDialog(1)

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

    private TextView text_out;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main_activity);

        initView();
       
    }

    private void initView() {
        text_out=findViewById(R.id.text_out);
        text_out.setOnClickListener(this);
    }

    @Override
    public void onClick(View view){
　　　　　　
        AlertDialog.Builder builder =new AlertDialog.Builder(this);
        builder.setTitle("退出")
       　       setMessage("确定要退出吗？")
        　　　　 setPositiveButton("确定", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
                // 关闭对话框
                dialogInterface.dismiss();
               // 退出程序
                VideoMonitor.this.finish();
            }
        })
               setNegativeButton("取消", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
            dialogInterface.dismiss();
            }
        });
        AlertDialog adialog= builder.create();
        adialog.show();
    }  
}