各位大大好，小弟最近刚接触Andorid
目前程式需要两个功能，爬了一些文章可是还是没看懂要如何应用
希望大大可以提供一些意见
1.想用下拉式选单提供秒数，让旁边的幻灯片可以按照选择的秒数变化
2.要在打开程式后，TextView持续更新文字
爬文有看到很多方法，但好像几乎都是按下按钮后才能变化
以下是目前的程式码，可是打开一秒后，app就会闪退
public class test extends AppCompatActivity {
private static final int msgKey1 = 1;
String random_text;
private TextView t1;
private Handler mHandler = new Handler() {
public void handleMessage(Message msg) {
super.handleMessage(msg);
switch (msg.what) {
case msgKey1:
t1.setText(testRandom2());
break;
default:
break;
}
}
};
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_test);
TextView t1 = findViewById(R.id.t1);
new TimerThread().start();
}
private String testRandom2() {
Random random = new Random();
String test1 = String.valueOf(random.nextInt(999) % (999 - 100 + 1) +
100);
return test1;
}
public class TimerThread extends Thread {
public void run() {
do {
try {
Thread.sleep(1000);
Message msg = new Message();
msg.what = msgKey1;
mHandler.sendMessage(msg);
} catch (InterruptedException e) {
e.printStackTrace();
}
} while (true);
}
}
}