Android中的Handler-Looper实现

2 回答

• 3

  附加到UI线程的处理程序 .

  正确 .

  android如何在没有新线程创建的情况下在同一个UI线程中运行runnable？

  任何线程，包括主应用程序（"UI"）线程，都可以在 Handler （或任何 View ，就此而言）上调用post（） .

  回复于 2024-04-27T06:30:08+08:00
• 5

  这是一个粗略的伪代码示例，说明如何使用处理程序 - 我希望它有帮助:)

  class MyActivity extends Activity {
  
      private Handler mHandler = new Handler();
  
      private Runnable updateUI = new Runnable() {
          public void run() {
              //Do UI changes (or anything that requires UI thread) here
          }
      };
  
      Button doSomeWorkButton = findSomeView();
  
      public void onCreate() {
          doSomeWorkButton.addClickListener(new ClickListener() {
              //Someone just clicked the work button!
              //This is too much work for the UI thread, so we'll start a new thread.
              Thread doSomeWork = new Thread( new Runnable() {
                  public void run() {
                      //Work goes here. Werk, werk.
                      //...
                      //...
                      //Job done! Time to update UI...but I'm not the UI thread! :(
                      //So, let's alert the UI thread:
                      mHandler.post(updateUI);
                      //UI thread will eventually call the run() method of the "updateUI" object.
                  }
              });
              doSomeWork.start();
          });
      }
  }
  

  回复于 2024-04-27T06:30:08+08:00