android中的主线程

android中的主线程不需要新建。

Thread.sleep设置程序阻塞。

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.bt).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                try {
                    Thread.sleep(1000);
                    System.out.print("The thread is running, is sleeping");
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        });
    }
}

 新建子线程后，按下Button,不会卡死，会立即弹起。

new Thread(){
                    @Override
                    public void run() {
                        try {
                            while (true){
                            sleep(1000);
                                System.out.print("Hello, this is the new thread!");
                            }
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    }
                }.start();